Guidelines for Transportation, Handling, and Use of Fast Pyrolysis Bio

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Guidelines for Transportation, Handling, and Use of Fast Pyrolysis Bio-Oil. 1. Flammability and Toxicity Anja Oasmaa,*,† Anssi Kal̈ li,† Christian Lindfors,† Douglas C. Elliott,‡ Dave Springer,‡ Cordner Peacocke,§ and David Chiaramonti∥ †

VTT, Technical Research Centre of Finland Pacific Northwest National Laboratory (PNNL), Richland, Washington, United States § CARE, Conversion And Resource Evaluation Ltd., Northern Ireland ∥ CREAR and RE-CORD, University of Florence, Florence, Italy ‡

ABSTRACT: An alternative sustainable fuel, biomass-derived fast pyrolysis oil or “bio-oil”, is coming into the market in Europe. Fast pyrolysis pilot and demonstration plants for fuel applications producing tonnes of bio-oil are in operation, and commercial plants are under design. There will be increasingly larger amounts of bio-oil transportation on water and by land, leading to a need for further specifications and supporting documentation. The properties of bio-oil are different from conventional liquid fuels and, therefore, may need to overcome both technical and marketing hurdles for its acceptability in the fuels market. Multiple material safety data sheets (MSDSs) are currently being used by different producers, but there is a desire to update these as more information becomes available. In order to standardize bio-oil, quality specifications are being adopted. The first bio-oil burner fuel standard in ASTM D7544 was approved in 2010. CEN standardization has been initiated in Europe. In the EU, a new chemical regulation system REACH (Registration, Evaluation and Authorisation of Chemicals) exists. Registration under REACH has to be perfomed if bio-oil is produced or imported into the EU. In the USA and Canada, bio-oil has to be filed under the TSCA (US Toxic Substances Control Act) and DSL (Domestic Substance List), respectively. In this paper, the state of the art on standardization is discussed, and new data for the transportation guidelines is presented. The focus is on flammability and toxicity.

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INTRODUCTION A relatively new fuel, biomass fast pyrolysis bio-oil, is coming into the market in Europe. The properties of bio-oil are different from conventional liquid fuels and, therefore, may need to overcome both technical and marketing hurdles. The major difference is the high polarity of bio-oil which makes it immiscible with mineral oils. Bio-oils are also acidic, unstable at high temperature or over prolonged storage periods of over 6 months, and are mainly nonvolatile components containing a large amount of chemically dissolved or emulsified water.1,27 The properties (Table 1) of the bio-oils must be taken into account in the determination of fuel oil qualities and their application. To promote the acceptance of bio-oil as a fuel, the methodology should be as similar as possible to that for conventional fossil fuel oils and give industry acceptable values. The properties and behavior of bio-oil has to be known, and suitable analytical methods have to be available. Standard fuel oil analyses have been systematically tested with fast pyrolysis bio-oils.1−5 Modifications to the standard test methods have been suggested, and some new methods have been provided. One new method has already been accepted as an ASTM standard. In order to standardize bio-oil quality in the market, specifications are being adopted.6−9 For promoting the acceptance of bio-oil as a fuel, the methodology should be as similar to that for mineral oils as possible. The first bio-oil burner fuel standard (Table 2) has recently been approved in ASTM D7544.9 © 2012 American Chemical Society

Table 1. Physical Properties of Fast Pyrolysis Bio-Oils and Mineral Oil U.S. No. 4 FO (Fuel Oil)1

a b

analysis

typical bio-oil

U.S. no. 4 FO

water, wt % solids, wt % ash, wt % nitrogen, wt % sulfur, wt % stability viscosity (40 °C), cSt density (15 °C), kg/dm3 flash point, °C pour point, °C LHV, MJ/kg pH distillability

20−30 below 0.5 0.01−0.2 below 0.4 below 0.05 unstablea 15−35b 1.10−1.30b 40−110c below −20 13−18b 2.5−3.0 not distillable

0.5 (water and sediment) 0.5 (water and sediment) 0.1 max varies 5.5−24 55 min −6 min

Unstable at high temperatures and for prolonged periods of time. Dependent on water content. cSee chapter on flammability.

In the EU, REACH (Registration, Evaluation and Authorisation of Chemicals),10 the new EU chemicals regulation, requires that chemical substances on their own, in preparations, and those which are intentionally released from articles have to be registered to the European Chemicals Agency (ECHA). Received: March 10, 2012 Revised: April 30, 2012 Published: May 4, 2012 3864

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duty is to contact the other pre-SIEF participants with a view to forming the SIEF. After the SIEF has been formed, the members will choose a lead registrant and make an agreement how the costs and work will be shared in the consortium. The Lead Registrant’s role is to submit the common part of the registration dossier ( Joint Submission) to ECHA when all tests needed for registration have been performed. After that, each registrant needs to submit his own dossier to the Joint Submission together with his company-specific information. The registration is completed when the registration fee has been received by the agency. Companies who are testing or developing a process can also apply for a so-called PPORD (Product and Process Oriented Research and Development), which extends the registration with five years.11 It is important to have data on the flammability, toxicity and corrosivity of the liquids. Where combined hazards occur, there is a preference order to assign the class for the liquids, i.e. one hazard outranks another. The hazard class and packing group for a material meeting more than one of these hazards shall be determined using the precedence table shown in Table 3. This table indicates which of the hazards should be regarded as the primary hazard. Table 3 is interpreted in the following way. On the axis on the left, take the given code, for example “6.1 I Dermal”. Then going across the table to see which hazard class takes precedence over it other potential properties, “6.1 I Dermal” is a lesser hazard than “8.1 Liquid”, so this hazard would be noted first. For “8.I Solid”, then “6.1 I Dermal” is a greater hazard and takes precedence. For the remaining “8,II Liquid; 8,II Solid; 8,III Liquid and 8,III Solid”, the “6.1 I Dermal” hazard continues to take precedence with regards to packing group. This can therefore be used by the supplier, knowing the detailed properties of the liquid to assign the most relevant packing group to his liquids. For pyrolysis liquids, the most common starting class may be Class 3 and/or 6 - Classes 4 and 5 have been omitted for clarity. Fast pyrolysis bio-oils do not have an official UN hazard identification code; therefore, the most appropriate NOS (not otherwise specified) code must be chosen based on the

Table 2. Pyrolysis Liquid Biofuels ASTM Burner Fuel Standard D75449

a

property

test method

specification

units

gross heat of combustion water content pyrolysis solids content kinematic viscosity at 40 °C density at 20 °C sulfur content ash content pH flash point pour point

D240 E203 D7579 D445a D4052 D4294 D482 E70-07 D93 procedure B D93

15 min 30 max 2.5 max 125 max 1.1−1.3 0.05 max 0.25 max report 45 min −9 max

MJ/kg mass % mass % mm2/s kg/dm3 mass % mass % deg C deg C

Without filtering.

Companies who manufacture or import 1 tonne or more of a chemical substance per year have to register their materials. The chemicals currently on the EU market, which meet the definition of phase in substances, have to be preregistered before December 1, 2008. The purpose of the preregistration in 2008 was to group all companies who produce or import the same substance under the same Substance Information Exchange Forum (SIEF). Companies who have preregistered their substances can benefit from extended registration deadlines. The deadline for registration depends on the tonnage band and the hazardous properties of the substances. Companies who failed to meet the preregistration deadline have to submit a full registration dossier before they can start to manufacture or import a substance. However companies who start manufacturing or importing 1 tonne or more of a chemical substance per year after December 1, 2008 can benefit from late preregistration provisions. The next step after preregistration is to check if the preregistered substances can be regarded as the same. If members of one pre-SIEF agree that their substance is not the same, they may split and seek to form/join another SIEF. The discussion in a pre-SIEF is usually led by the SIEF Formation Facilitator (SFF). The SFF can be anyone of the preregistrants, and his Table 3. Hazard Precedence Tablea 4.2 3I 3 II 3 III 4.1 II 4.1 III 4.2 II 4.2 III 4.3 I 4.3 II 4.3 III 5.1 I 5.1 II 5.1 III 6.1 I dermal 6.1 I oral 6.1 II inhalation 6.1 II dermal 6.1 II oral 6.1 III

4.2 4.2

4.3 4.3 4.3 4.3 4.3 4.3 4.3 4.3

5.1 I

5.1 5.1 5.1 5.1 5.1 5.1 5.1

5.1 II

4.1 4.1 4.2 5.1 4.3 4.3 5.1

5.1 III

6.1 I dermal

6.1 I oral

6.1 II

6.1 III

4.1 4.1 4.2 4.2 4.3 4.3 4.3

3 3 6.1 6.1 6.1 6.1 6.1 6.1 6.1 6.1 5.1 6.1 6.1

3 3 6.1 6.1 6.1 6.1 6.1 4.3 4.3 6.1 5.1 5.1 6.1

3 3 6.1 4.1 6.1 4.2 6.1 4.3 4.3 6.1 5.1 5.1 6.1

3 3 3 4.1 4.1 4.2 4.2 4.3 4.3 4.3 5.1 5.1 5.1

8.I liquid

8.I solid

3 8 8

8 8 4.3 8 8 5.1 8 8 8 8 8 8 8 8

8.II liquid

8.II solid

3 3 8 8 8 8 8 4.3 8 8 5.1 8 8 6.1 6.1 6.1 6.1 8 8

4.2 8 4.3 4.3 8 5.1 5.1 8 6.1 6.1 6.1 8 8 8

8.III liquid

8.III solid

3 3 3 4.1 8 4.2 8 4.3 4.3 8 5.1 5.1 8 6.1 6.1 6.1 6.1 6.1 8

4.2 4.2 4.3 4.3 4.3 5.1 5.1 5.1 6.1 6.1 6.1 6.1 6.1 8

4.1 4.1 4.2 4.2 4.3 4.3 4.3 5.1 5.1 5.1 6.1 6.1 6.1 6.1 6.1 8

a

Note: Class identified in the column intersections take precedence over the class/division in the row or column head, e.g., 6.1 I Dermal" is a lesser hazard than “8.1 Liquid”, so this hazard would be noted first. 3865

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flammable vapor at a temperature at or below the maximum transport temperature. In some cases, the producer may be able to justify a case where the liquids are not subject to dangerous goods requirements for shipment, i.e.: Liquids meeting the definition in 2.3.1.2 with a flash point of more than 35 °C which do not sustain combustion need not be considered as flammable liquids for the purposes of these Regulations. Liquids are considered to be unable to sustain combustion for the purposes of these Regulations (i.e., they do not sustain combustion under defined test conditions) if: (a) They have passed a sustained combustibility test (see SUSTAINED COMBUSTIBILITY TEST prescribed in the Manual of Tests and Criteria, Part III, subsection 32.5.2); or (b) Their fire point according to ISO 2592:2000 is greater than 100 °C; or (c) They are water miscible solutions with a water content of more than 90% by mass.

properties of the bio-oils. Under the UN guidance, there is a range of potential UN codes for bio-oils, depending on their properties. The transportation regulations8,13,14 specify the safety classes based on flash point. The flash point of petroleum oil is measured to indicate the maximum temperature at which it can be stored and handled without serious fire hazard. If the flash point is too low, it causes the fuel to be subject to flashing and possible continued ignition and explosion.15 Flash points of diesel, vegetable oils, and biodiesels also exhibit considerable variations16 (Table 4) due to various production process yielding variations in the final chemical composition. Table 4. Flash Points of Various Fuels and Liquids fuel jet A/A-1 fuel

reference specified FPa, standard (analysis range of measured deg C method for FP) FP (and ref) >38

diesel

>55

straight vegetable oil

>220

sunflower oil cold extraction

250−253

industrial extraction (mechanical, no hexane) biodiesel (methyl esters)

250

a

>120

ASTM D 1655 (ASTM D 93)

Exxon Mobile, World Jet Fuel Specifications 2005 EN590 9316 (EN ISO 2719) 100−17017 DIN V 51605 174−27718 (DIN EN ISO 150−27719 2719) 241−33016 23620 University of Florence data DIN EN ISO 2719 DIN EN ISO 2719

UNECE

Pyrolysis bio-oils may be classed as “toxic” (class 6), depending on their chemical composition and properties. The classes of compounds which are found in fast pyrolysis liquids in the UN Manual are mainly class 3, but some are also class 6.1, like phenols which are present in bio-oil in concentrations >0.1 wt %. Due to this, pyrolysis liquids are classed as 3(a) overall classification, using a cross classification to derive the most appropriate classification for complex mixtures. If the concentration of acetic acid is below 10 wt %, there is no need to add additional labeling to highlight corrosiveness in the liquids. The purpose of this paper is to present new results on flammability and toxicity and suggest preliminary guidelines for transportation. Part 2 will present more new data, such as material testing, after which final conclusions for guidelines can be drawn. The aim is to prepare an updated MSDS including REACH guidelines for fast pyrolysis bio-oils.

EN 14214− 128−16221 EN14213 (EN ISO 3679)

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FP = flash point.

NORMS AND STANDARDS CAS Number. Fast pyrolysis bio-oils have to be registered before commercial fuel oil production. IEA Bioenergy Task 34 Pyrolysis suggested the definition for fast pyrolysis bio-oil under a new CAS number CAS RN 1207435-39-9 (March 1, 2010): Fast Pyrolysis Bio-oil. Liquid condensate recovered by thermal treatment of lignocellulosic biomass at short hot vapor residence time (typically less than about 5 s) typically at between 450 − 600 °C at near atmospheric pressure or below, in the absence of oxygen, using small (typically less than 5 mm) dry (typically less than 10% water) biomass particles. A number of engineered systems have been used to effect high heat transfer into the biomass particle and quick quenching of the vapor product, usually after removal of solid byproduct “char”, to recover a single phase liquid product. Bio-oil is a complex mixture of, for the most part; oxygenated hydrocarbon fragments derived from the biopolymer structures. It typically contains 15−30% water. Common organic components include acetic acid, methanol, aldehydes and ketones, cyclopentenones, furans, alkylphenols, alkyl-methoxy-phenols, anhydrosugars, and oligomeric sugars and water-insoluble lignin-derived compounds. Nitrogen- and sulfur-containing compounds are also sometimes found depending on the biomass source.

Even though valid for several biomass derived liquids and other fuels, the method for flash point is not suitable for fast pyrolysis oils because they contain a high amount of water evaporating significantly below 100 °C and extinguishing the possible flame caused by low-boiling volatiles.1 Therefore, another test method to measure flammability appropriately for fast pyrolysis liquids is needed. If the liquids can be shown to be incapable of sustaining combustion, then they need not be shipped as flammable liquids. According to UN Guidance on Transportation of Dangerous Goods (16th Edition, 2009 (UNECE, 2009)),22 a flammable liquid (class 3) is defined as follows: Flammable liquids are liquids, or mixtures of liquids, or liquids containing solids in solution or suspension (for example, paints, varnishes, lacquers, etc., but not including substances otherwise classified on account of their dangerous characteristics) which give off a flammable vapor at temperatures of not more than 60.5 °C, closed-cup test, or not more than 65.6 °C, open-cup test, normally referred to as the flash point. UNECE

This class also includes the following: (a) liquids offered for transport at temperatures at or above their flash point and (b) substances that are transported or offered for transport at elevated temperatures in a liquid state and which give off a

IEA Bioenergy Task 34 Pyrolysis 3866

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REACH. In the EU, REACH applies. REACH registration for fast pyrolysis liquid started in 2008 by preregistration the substance under CAS number 94114-43-9 (wood, hydropyrolyzed). Since then, 36 companies have made the preregistration under this CAS number. The list of preregistered companies under CAS number 94114-43-9 is quite wide consisting of both slow and fast pyrolysis companies and some consulting companies. For this reason IEA Bionergy Task 34 recommends to split the pre-SIEF into the following: (1) Slow pyrolysis SIEF (CAS number 94114-43-9) (2) Fast pyrolysis SIEF (CAS number 1207435-39-9) In the REACH-It system, it is however not possible to split the old SIEF (CAS number 94114-43-9) into two new SIEFS. According to ECHA, it is up to the member registrants to agree on the substance sameness and make sure that they form a SIEF of an unambiguous substance. For this reason the member registrants of the old SIEF have to decide between themselves which companies belongs to fast pyrolysis companies and do the REACH registration with the new CAS number before the actual work can start. Another way to perform the REACH registration for fast pyrolysis bio-oil would be to do it in direct agreement with other fast pyrolysis companies. IEA Bioenergy Task 34 Pyrolysis will provide part of the data needed for the registration of fast pyrolysis bio-oil. Most of this data is presented in this paper. The data will be created under CAS number CAS RN 1207435-39-9. You can follow the progress through the webpages: http://www. pyne.co.uk/. In the United States, the bio-oil is to be listed under the TSCA (US Toxic Substances Control Act). ASTM Standards. Fuel oil specifications are needed for additional commercial applications of bio-oil. Long-term continuous combustion tests are needed to specify the possible fuel oil grades to meet the emission limits. These limits are different in the EU and USA/Canada. The second burner fuel standard being developed is aimed to specify lower solids (0.25 wt %) and ash (0.15 wt %) contents. EN standards. In the EU, CEN standardization has been initiated. CEN has obtained a mandate for standards on pyrolysis oils produced from biomass feedstocks to be used in various energy applications or intermediate products for subsequent processing. CEN has been given the mandate to develop the following: (a) A European standard for a quality specification for pyrolysis oil replacing heavy fuel oil in boilers (b) A European standard for a quality specification for pyrolysis oil replacing light fuel oil in boilers (c) A technical specification for a quality specification for pyrolysis oil replacing fuel oils in internal combustion engines (d) A technical specification for a quality specification for pyrolysis oil suitable for gasification feedstock for production of syngas and synthetic biofuels (e) A technical specification for a quality specification for pyrolysis oil suitable for mineral oil refinery coprocessing. The first three (a−c) documents above are to be given precedence and be developed as soon as possible. The last two (d and e) are to be given lower priority and developed at a later stage or as market developments dictate. The work is planned to be undertaken in a working group. The working group is composed of a chairman to guide the discussions and to conclude technical decisions of the experts around the table and of experts, also from outside Europe, with experience of producing, using, transporting, and testing the product.

Article

FLAMMABILITY

Flash Point. It has been attempted to measure the flash point of bio-oil using both the open and closed cup methods. ASTM D 93 (ASTM D 93/IP 34) uses a Pensky−Martens closed cup tester. Its primary use is for materials having a flash point temperature range of 40−360 °C. The sample is heated at a slow, constant rate with continual stirring. A small flame is directed into the cup at regular intervals with simultaneous interruption of the stirring. The flash point is the lowest temperature at which the test flame ignites the vapor above the sample. ASTM D 92 is the open cup method whose primary use is for materials having a flash point of 79 °C and above. The difference from the closed cup is that it has no cover and no stirring. In bio-oil, there are some light compounds evaporating at near ambient temperatures, which may cause a small shortduration flash in the presence of oxygen and heat. The amount of these compounds is typically below 5 wt % of the total oil. These compounds include light aldehydes (acetaldehyde bp 21 °C, propanal, butanal, crotonaldehyde), ketones (acetone bp 56 °C, 2-butanone, 2,3-butanedione, 2,3-pentandione, cyclopentanone, 2-propanone, hydroxypropanone), alcohols (methanol bp 65 °C, 2-propanol), esters (methylformate), furans (bp 31 °C) and furfurals, and acids (acetic bp 118 °C, propanoic acids). Flash Point of Fast Pyrolysis Bio-Oil. The flash point of one pine pyrolysis bio-oil was measured by both open and closed cup methods (Table 5). The results varied even though the Table 5. Flash Point of a Pine Pyrolysis Bio-Oil by Open and Closed Cup Methodsa flash point, °C laboratory

open cup ASTM D92

closed cup ASTM D93

lab 1 VTT lab 2 lab 3

109 NT NT >100

100 53 52 50.5

a

NT = not tested. Labs 1−3 are all accredited private laboratories who are experienced performing these analyses for the industry.

measurements were conducted in accredited laboratories. The reason for this is that the first flash is very difficult to observe due to the low amount of volatile compounds and high amount of water which evaporates and suppress the flame at various temperatures. The method for flash point has been proved not to be suitable for fast pyrolysis bio-oils. Sustained Combustibility Test. The method is described in the UN Manual of Tests and Criteria, Part III: 32.5.2. The test (Figure 1) is used to determine if a substance sustains combustion when heated under the test conditions and exposed to a flame: a metal block with a concave sample well is heated to a specified temperature, 2.0 mL of the substance is transferred to the well, a standard flame is applied to the well and subsequently removed, and the ability of the substance to sustain combustion is noted. Sustained Combustibility Test for Fast Pyrolysis Bio-Oil. Pyrolysis oils chosen for the test23 were VTT’s and Metso’s biooils from pine and Metso’s forest residue bio-oil as it was and by addition of 5 wt % IPA. No real flash was observed. None of the oils sustained combustion either on test temperature (60 °C) or at elevated temperature (75 °C). 3867

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Table 6. Composition, Information on Ingredients

Figure 1. Test equipment for sustained combustibility test.

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TOXICITY A fast pyrolysis bio-oil produced from spruce was analyzed as a representative “typical” bio-oil. The production of this liquid was carried out using a 5 kg/h fluidized bed fast pyrolysis unit at 500 °C with a gas/vapor product residence time of less than 2 s. A 70 wt % bio-oil was produced containing 17.6 wt % water and 0.1 wt % solids. The mass balance closure for the test was 95%. This bio-oil was selected within the BioTox as a representative for further analysis. Although it can be argued that bio-oils produced from different biomass feedstocks using different reactor systems can have different compositions (and therefore different toxicities), the authors agree with the BioTox group that this oil should serve as a reasonable representative of wood-derived fast pyrolysis bio-oil. The results with other biomasses will likely have some differences in bio-oil composition, although the differences between hardwoods and softwoods are not as great as in comparing wood to straws and stovers and certainly algae-derived bio-oils would be expected to be much different. The EU funded BIOTOX project24 has provided data on the toxicity of biomass derived pyrolysis liquids. Unfortunately, the data combined both fast and slow pyrolysis oils. In IEA Bioenergy Task 34, this data was forwarded to toxicity experts and conclusions relevant to fast pyrolysis bio-oils are presented in this paper. Subsequent tests included dermal irritation and skin sensitization, acute oral toxicity and 7-day oral toxicity, and in vivo and in vitro mutagenesis tests. Also, tests evaluated the environmental effects of bio-oil release including algal growth inhibition, toxicity to Daphnia magna and biodegradability. In order to assess bio-oil biodegradability25 and to be able to set up recommendations and MSDS, the biodegradability of nine different fast pyrolysis bio-oils was measured using the Modified Sturm test 301B25 which is the conventional test used to assess oil biodegradation. The toxicological information are given for one pyrolysis material which was considered as a representative fast pyrolysis oil; i.e., BioTox-21. The composition and other information of the sample are seen in Table 6.

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overall composition (as received)

wt %

pyrolytic lignin water GC identified GC unidentified unknown class (as received)

15.7 17.6 19.1 1.2 46.4 wt %

acids aldehydes furans guaiacois ketones phenols pyrans sugars other total

2.2 6.8 1.4 2.6 2.9 0.2 0.1 2.5 0.2 18.8

elemental analysis (as received)

wt %

C H N O

44.6 7.1 0.36 48 (by difference)

specific PAHs (as received)

ppm

fluorene phenanthrene anthracene fluoranthene pyrene benzo(a)antracene chrysene benzo(a)fluoranthene benxo(a)pyrene indenopyrene dibenzoanthracene benzoperylene total

0.13 0.21 0.06 0.06 0.26 0.03 0.02 0.01 0.01 0.30 0.01 ND 0.02

○ Method: Rats administered a single oral dose, observed for 14 days, body weight recorded and tissues examined at necropsy. ○ Results: ■ No change in body weight or weight gain during the 14-day observation period. ■ No mortality. ■ No apparent abnormalities upon macroscopic examination of main organs. ■ Symptoms of toxicity included hypoactivity, sedation, piloerection (hair standing on end), unsteady gait. ○ Conclusions: ■ LD50 >2,000 mg/kg body weight. • 7-day oral toxicity in rats, EC Directive 96/54, B7, September 30, 1996; OECD Guideline No. 407, July 27, 1995. ○ Purpose: To evaluate BioTox-21 for toxicity following daily oral administration for 7 days. ○ Methods: Male and female rats administered BioTox-21 by gavage for 7 days at doses of 150, 500, or 1500 mg/(kg day). Clinical symptoms and mortality are checked daily. Body weight is recorded three times and food consumption twice during the dosing period. Upon completion of the dosing period, animals were sacrificed and a complete macroscopic examination was performed. Selected organs were weighed, and macroscopic lesions were preserved. ○ Results: ■ No premature deaths during the study. At 1500 mg/(kg day): Hypersalivation; decreased body weight gain with accompanying reduction in food consumption. At 500 mg/(kg day): No clinical signs; decreased body weight gain with accompanying reduction in food

ACUTE TOXICITY • LD50 (oral, female rats), EC Directive 2004/73/EC, B.1 tris, April 29, 2004; OECD Guideline No. 423, December 17, 2001. ○ Purpose: To estimate the acute oral toxicity. 3868

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consumption in males; one male with dilatation of the duodenum. At 150 mg/(kg day): Slight reduction in body weight gain in females. • Acute dermal irritation (rabbits), Directive 2004/73/EC, B.4, April 29, 2004; OECD Guideline No. 404, April 24, 2002. ○ Purpose: To determine whether BioTox-21 induces skin irritation. ○ Methods: One New Zealand rabbit was treated dermally (6 cm2) with BioTox-21 (0.5 mL undiluted test material) for 3 min, 1, or 4 h and evaluated at 1, 24, 48, and 72 h after application. Application site examined for irritation (erythema and edema) and corrosion (full thickness destruction of the skin). ○ Results: Slight erythema observed after 3 min exposure; however after 1 h exposure the erythema increased in severity and slight edema occurred. After 72 h of exposure, the animal was euthanized due to the gravity of the cutaneous reaction and the test ended. ○ Conclusion: BioTox-21 is corrosive when applied topically to rabbits.

MUTAGENICITY • Bacterial reverse mutation assay, Commission Directive 2000/32/EC, B13, June 8, 2000; OECD Guideline No. 471, July 21, 1997. ○ Purpose: To determine whether BioTox-21 causes bacteria to mutate. ○ Methods: Five strains of bacteria (TA 98, TA 100, TA 102, TA 1535, and TA 1537) were exposed to the test material at doses that were nontoxic to the bacteria. The test material was evaluated with and without metabolic activation by S9. ○ Results: Bio-Tox-21 produced mutagenic activity with and without metabolic activation in some strains (TA 98, TA 100, TA 102). ○ Conclusion: These results indicate that the test material contains both direct acting mutagens and compounds that require metabolic conversion to produce mutagenic activity. • Bone marrow micronucleus test using oral administration to mice, Commission Directive No. 2000/32/EC, B12, June 8, 2000; OECD Guideline No. 474, July 21, 1997. ○ Purpose: To evaluate the test material for its ability to induce chromosome changes or damage to the mitotic apparatus of bone marrow cells in mice. This assay has the ability to detect agents that cause chromosome breaks (clastogenesis) and those that cause loss of whole chromosomes (aneuploidy). ○ Methods: The test material was administered orally to mice twice (24 h apart), the animals sacrificed, femur bone marrow obtained, and cell spreads prepared on microscope slides. For each animal, the number of micronucleated polychromatic erythrocytes (MPE) were counted. The polychromatic (PE) and normochromatic (NE) erythrocyte ratios were determined after scoring 1000 erythrocytes.

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○ Results: There were no significant changes in the frequency of micronucleated cells in mice treated with BioTox-21 oil. ○ Conclusion: Neither chromosome damage nor changes to the mitotic apparatus were observed in bone marrow cells following oral administration of BioTox-21 to mice. • In vitro micronucleus test in L5178Y TK± mouse lymphoma cells, OECD Guideline No. 487, draft dated June 14, 2004. ○ Purpose: To determine the potential of BioTox-21 to increase the frequency of micronucleated cells. Micronuclei in the cytoplasm of interphase cells may originate from acentric fragments (chromosome fragments lacking a centromere) or from chromosomes that are unable to migrate with the other chromosomes during anaphase of cell division. The assay is used to detect clastogenic and aneugenic agents because these changes are associated with early events in tumor development. ○ Methods: Mouse lymphoma cells were exposed to BioTox-21 at doses ranging from 5−2500 μg/mL. Cytotoxic concentrations were determined and the test material evaluated for mutagenicity at minimally toxic doses. Addition of S9 to the cell culture media provided information on whether mutagenic activity is due to direct acting compound(s) or whether metabolic activation is required for adverse effects to occur. ○ Results: Toxicity tests were used to select doses for mutagenicity assays. The degree of cytotoxicity was dose dependent both with and without metabolic activation with S9. A modest nondose related response in mutagenicity was observed in the absence of metabolic activation. With S9 there were no significant changes in mutagenic activity. ○ Conclusion: BioTox-21 has little or no mutagenic (clastogenic or aneugenic) activity as measured by the in vitro micronucleus assay in mouse lymphoma cells.

ECOTOXICOLOGY EVALUATION • Algal growth inhibition, Commission Directive 92/69/ EEC, C.3, July 31, 1992; OECD Guideline No. 201, July 7, 1984. ○ Purpose: To assess the effects of BioTox-21 oil on the growth of unicellular algae in a 72-h period. ○ Method: Algae grown at concentrations of 1, 10, and 100 mg test material/L and growth and growth rates assessed relative to unexposed controls. ○ Conclusion: There was no significant inhibition of algal growth up to 100 mg/L. • Acute toxicity to Daphnia magna, Commission Directive 92/69/EEC, C.2, July 31, 1992; OECD Guideline No. 202, April 4, 1984. ○ Purpose: To assess the acute toxicity of the test material to Daphnia in a 48-h period. ○ Method: Twenty Daphnia were exposed to BioTox-21 at concentrations of 1, 10, and 100 mg/L. Since Daphnia are small it is difficult to determine whether the organism is dead, therefore immobilization (the algae is incapable of swimming dx.doi.org/10.1021/ef300418d | Energy Fuels 2012, 26, 3864−3873

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The product is a mixture and also contains some toxic components. If the LD50 values and the percentage of the components in the mixture are known, the classification can be made by applying a certain calculation formula found in the transport regulations. The test results of BioTox-21 for rats (LD50 oral) was >2000 mg/kg. Because the result is greater that the limit value (300 mg/kg), the product is not toxic. For testing environmental hazards, the basic elements are the following: • Acute aquatic toxicity • Chronic aquatic toxicity • Potential for or actual bioaccumulation • Degradation (biotic or abiotic) for organic chemicals Tests results for BioTox-21 showed following results: • Algae 72 h 100 mg/L (more than limit 10 mg/L) • Daphnia 48 h 100 mg/L (more than limit 10 mg/L) • Aerobic biodegradability 28 days/42% Because the Algae/Daphnia 78/48 h values exceed the limits, biodegradability does not have to be taken into consideration. So, this is not environmentally hazardous according to the transport regulations, but may be give Aquatic chronic 4 (=“safety net”) according to GHS/CLP regulations. Classification criteria of other classes (1, 2, 4, 5, and 7) is not relevant to this product. On the basis of the Table 7 for the “typical” bio-oil, it seems that the product should be classified as a class 8 (corrosive) product. This conclusion is based on both the corrosivity and environmentally hazardous conclusions drawn. To make a final classification, all required tests should be done according to the relevant transport regulations, referring to UN Manual of Tests and Criteria, OECD test, and others as applicable. It should also be noted that the variations between different products could lead to different classifications. For bio-oils there is no UN number assigned at the moment. If further testing shows that the properties for bio-oils are mostly the same, it may be possible to suggest a new UN number for the product. This suggestion should be made to UN, normally by a competent authority, or an association. Suggestion for transport classification (material safety data sheet, Section 14 Transport Information): UN NUMBER: 3265, PROPER SHIPPING NAME: CORROSIVE LIQUID, ACIDIC, ORGANIC, NOS (contains x, y *), CLASS: 8, PACKING GROUP: III, ENVIRONMENTAL HAZARDS: NO (*) = relevant chemical/technical names which have affected to the classification (e.g., acetic acid)

within 15 s after a gentle stimuli) was used as an indicator or toxicity. Immobilization was recorded at 0, 24, and 48 h after start of exposure. ○ Conclusion: There was no significant acute toxicity up to 100 mg/L. • Aerobic biodegradability in fresh water based on OECD 301B, Modified Sturm Test. ○ Purpose: To measure the extent of aerobic biodegradation of BioTox-21 to help determine whether it is a hazard to the environment in case of accidental discharge. ○ Method: The test is based on a modified Sturm procedure. The test is run in a controlled volume of mineral medium inoculated with activated sludge from a sewage treatment plant (32 mg/L SS) containing 15 mg/L dissolved organic carbon from BioTox-21. Test material degradation was recorded for 28 days by measuring the amount of carbon dioxide released following trapping in barium hydroxide. Diesel was run under the same conditions as a reference material. It was assumed that biodegradation followed simple firstorder kinetics. ○ Results: BioTox-21 degradation was observed since carbon dioxide was released from the incubation media. Degradation began immediately without a lag phase indicating a fast biological response. This may have been aided by the acidic nature of the test material. Relative to diesel, BioTox-21 was initially degraded at about three times the rate so that after 28 days approximately 42% of the test material was eliminated compared to about 24% for diesel. ○ Conclusion: It appears that the pyrolysis oil is biodegradable and has a higher biodegradability potential than heavier fuel like diesel.

TRANSPORTATION GUIDELINES

Fast pyrolysis bio-oil is a new type of fuel. The composition of different bio-oils is not exactly the same, but in general they are acidic, unstable at high temperatures or over long storage periods, highly polar, and mainly nonvolatile components containing a large amount of chemically dissolved of emulsified water. The most important variation in test results, which affect the transport classification, is the flashpoint. If the flashpoint is ≤60 °C (closed cup test), the product is classified as a flammable liquid. The flashpoint is difficult to measure with existing test methods, due to the low amount of volatile compounds and high amount of water which evaporates and suppresses the flame at various temperatures. In case it is shown that the product does not sustain combustion, the flashpoint need not to be taken into consideration. The test report23 from VTT shows that two different bio-oils, which were tested, did not sustain combustion. For this reason the product is not classified as a flammable liquid (class 3). Corrosiveness should be tested against dermal exposure and also for steel. For steel the test result was negative. However, for rabbits the test results of BioTox-21 gives indications that the product is slightly corrosive (estimated class 8, packing group III). Transport classification is not based directly on pH value. The pH for these products is normally >2.5.

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QUALITY CONTROL AND QUALITY ASSURANCE Flammability. Flash point measurements were carried out in authorized laboratories using standard test methods. A sustained combustibility test23 was carried out by VTT Expert Services Ltd. Testing laboratory T001 is accredited by FINAS, Finnish Accreditation Service. The present accreditation decision is valid until 31.12.2013. Information about the scope and the current status of the accreditation is available on the web page www.finas.fi. The body conforms to the requirements of the following standard: SFS-EN ISO/IEC 17025:2005. Toxicity. Toxicological and ecotoxicological tests in EU Biotox project24 were carried out using OECD (Organisation for Economic Co-operation and Development) guidelines. OECD Principles of Good Laboratory Practice ensure quality and reliable test data related to chemical safety in the framework of the Mutual Acceptance of Data (MAD). The OECD Test Guidelines and 3870

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not classified as environmentally hazardous

algae 72 h: 100 mg/L daphnia 48 h: 100 mg/L Aerbic biodegradability 28 days: 42% 10 mg/L 10 mg/L OECD tests

not environmentally hazardous

related documents are used by government, industry, and laboratories to test and assess chemicals. Transportation Guidelines. The evaluation report26 of transport classification for fast pyrolysis oils was prepared by Dangerous Goods Management Finland Oy (DGM). The organization (est. 1988) is devoted to packing, storage and transport, consulting, and professional training in the field of moving dangerous goods. All of DGM’s activities are performed in accordance with the global safety standards: the rules and regulations of IATA/ICAO−IMO−ADR− RID, for the safe handling and transport of hazardous goods. In this study, the following regulations and studies were used: • UN Recommendations on the Transport of Dangerous Goods 17th revised edition • UN Manual of Tests and Criteria fifth revised edition • European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR) applicable as from January 1, 2011 • International Maritime Dangerous Goods Code (IMDG) Amendment 35-10 • IATA Dangerous Goods Regulations 2012, 53rd Edition • Sustained combustibility test series, Test Report VTT-S-72-11 • Guidelines for Storage, Handling, Transportation and Use of Fast Pyrolysis Bio-Oil, Draft January 24, 2012 • Test results for BioTox-21, which were used for evaluating toxicity, corrosiveness and environmental hazards • Former tentative classification study based on material safety data sheets submitted by VTT Evaluation is based on comparison of known properties with existing transport classification criteria and test methods. Some of test results were not possible to evaluate in details, because it was unclear, whether the test methods were in line with the test requirements of the UN Manual of tests and criteria.

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CONCLUSIONS Essential data has been created especially on flammability, and toxicity. Standard flash point analyses are not suitable for fast pyrolysis bio-oils. A specific ignition test was carried out for proper classification of fast pyrolysis bio-oil. It was proven that pyrolysis liquids are incapable of sustain combustion and can be classified as nonflammable liquids. BioTox-21, the bio-oil product from the pyrolysis of wood from spruce using a fluidized bed conversion process, has had limited toxicological evaluation. The available data indicates that acute oral toxicity from a single dose is high (>2500 mg/kg) which puts it in the “slightly toxic” category. The most severe adverse effect was the “irritation/corrosion” changes observed when it was applied dermally to a rabbit. Because of the severity of the dermal changes (erythema/ edema i.e., burns) and for ethical reasons, the eye irritation test was not run. These effects are most likely due to phenols, aldehydes, and/or ketones shown to be present in the test material. Thus, skin and eye protection will be necessary for plant workers. The mutagenic activity for BioTox-21 was ambiguous in that it gave a slight positive response in the bacterial forward mutation assay, a modest response in the mouse lymphoma cell culture assay in the absence of metabolic activation, but was negative in the mouse bone marrow micronucleus test. On the basis of these results, it is recommended that a life span

Modified from the table in ref 26. a

not relevant for this product not relevant for this product because only one type of hazard other transport classifications classification of mixtures

environmentally hazardous

class 6.1, toxic substances class 9, miscellaneous dangerous goods toxic

aquatic toxicity bioaccumulation degradation

LD50 ≤ 300 mg/kg (oral)

not classified as toxic substance not corrosive for steel, corrosive for aluminum >2000 mg/kg (oral, rat) UN test manual

probably slightly corrosive (PG III) slightly corrosive for rabbit pH > 2.5 class 8, corrosive substance corrosivity corrosive

full thickness destruction of intact skin tissue metal corrosion of steel/ aluminum rat testing

if the product does not sustain combustion, it does not need to be classified as flammable liquid this method does not apply to bio-oil does not sustain combustibility

≤60 °C (closed cup test) does not sustain combustibility OECD tests flashpoint sustained combustibility class 3, flammable liquids flammable

conclusion fast pyrolysis bio-oils limit values existing test methods transportation classification property

Table 7. Summary Table of Transportation Guidelinesa

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(2) Elliott, D. C. Analysis and upgrading of biomass liquefaction products, Final report; IEA Co-operative project D1 Biomass Liquefaction Test Facility Project, Pacific Northwest Laboratory, Richland, WA, 1983; Vol. 4. (3) Rick, F.; Vix, U. Biomass Pyrolysis Liquids Upgrading and Utilization; Bridgwater, A. V., Grassi, G., Eds.; Elsevier Applied Science: London, UK, 1991; pp 177−218. (4) Oasmaa, A.; Peacocke, C. A guide to physical property characterisation of biomass-derived fast pyrolysis liquids; VTT Publications: Espoo, Finland, 2001; VTT Vol. 450; http://www.vtt.fi/inf/ pdf/publications/2001/P450.pdf. (5) Oasmaa, A.; Leppämäki, E.; Koponen, P.; Levander, J.; Tapola, E. Physical characterisation of biomass-based pyrolysis liquids Application of standard fuel oil analyses; VTT Publications: Espoo, Finland, 1997; VTT Vol. 306;http://www.vtt.fi/inf/pdf/publications/1997/P306.pdf. (6) Gust, S.; McLellan, R. J.; Oasmaa, A.; Ormrod, D.; Peacocke, G. V. C. Determination of norms and standards for bio-oil as an alternative renewable fuel for electricity and heat production. Fast Pyrolysis of Biomass: A Handbook; Bridgwater, A. V., Ed.; Aston University, BioEnergy Research Group, 2005; Vol. 3, pp 9−18. (7) Oasmaa, A.; Peacocke, C.; Gust, S.; Meier, D.; McLellan, R. Energy Fuels 2005, 19 (5), 2155−2163. (8) Peacocke, G. V. C.; Russell, P. A.; Jenkins, J. D.; Bridgwater, A. V. Biomass Bioenergy 1994, 7 (16), 169−177. (9) Oasmaa, A.; Elliott, D. C.; Müller, S. Progress Sustainable Energy 2009, 28 (3), 404−409, DOI: 10.1002/ep.10382. (10) ECHA. http://echa.europa.eu/web/guest/about-us. (11) Oasmaa, A. Registration of Fast Pyrolysis Liquids under REACH. PYNE, 2008, (25 December), p 9; http://www.pyne.co.uk/ Resources/user/PYNE%20Newsletters/PyNe%20news%2025.pdf. (12) Peacocke, G. V. C.; Bridgwater, A. V. Progress in Thermochemical Biomass Conversion; Bridgewater, A. V., Ed.; 2001; Vol. 2, pp 1482− 1499. (13) Peacocke, G. V. C.; Meier, D.; Gust, S.; Webster, A.; Oasmaa, A.; McLellan, R. Determination of norms and standards for biomass derived fast pyrolysis biooils; EU Contract No. 4.1030/C/00-015/2000, Final report, 2003. (14) Dyroff, G. V. Manual on significance of tests for petroleum products, 6th ed; ASTM: Philadelphia, 1993. (15) Demirbas, A. Prog. Energy Combust. Sci. 2005, 31, 466−487. (16) Sidibé, S. S.; Blin, J.; Vaitilingom, G.; Azoumahet, Y. Renewable Sustainable Energy Rev. 2010, 14, 2748−2759. (17) (a) Guo, Y.; Wie, H.; Yang, F.; Li, D.; Fang, W.; Lin, R. J. Hazard. Mater. 2009, 167, 625−629. (b) ASTM standard D 6751; ASTM: Philadelphia. (18) Goering, E.; Schwab, W.; Daugherty, J.; Pryde, H.; Heakin, J. Trans ASAE 1982, 25, 1472−1483. (19) Misra, R. D.; Murthy, M. S. Renewable Sustainable Energy Rev. 2010, 14, 3005−3013. (20) Chiaramonti, D.; Oasmaa, A.; Solantausta, Y.; Peacocke, C. The use of biomass derived fast pyrolysis liquids in power generation: engines and turbines; 2009; publication No. 561; http://www.vtt.fi/inf/ julkaisut/muut/2009/P561_2007_Chiaramonti.pdf. (21) Sridharan, R; Mathai, I. M. J. Sci. Ind. Res. 1974, 33, 178−87. (22) EN590 and EU Fuel Quality Directive (Directive 2009/30/EC of the European parliament and of the Council of April 23, 2009 amending Directive 98/70/EC as regards the specification of petrol, diesel, and gas-oil and introducing a mechanism to monitor and reduce greenhouse gas emissions and amending Council); Europeon Union: Brussels, 2009. (23) Kaukanen, K. Sustained combustibility test series; VTT: Finland, January 17, 2011; Test report No. VTT-S-72-11. (24) An assessment of bio-oil toxicity for safe handling and transportation. EU-BIOTOX. EU Contract no. NNE5-2001-00744BIOTOX Part I: Publishable Final Report. September 2005; http:// www.pyne.co.uk/Resources/user/docs/BIOTOX%20Final%20Publishable%20report.pdf. (25) Blin, J.; Voll, G.; Girard, P.; Bridgwater, T.; Meier, D. Fuel 2007, 86, 2679−2686.

skin painting assay be conducted to determine whether the test material is carcinogenic. This is especially important since the test material contains measurable amounts of polycyclic aromatic hydrocarbons (PAHs) including benzo(a)pyrene and benzo(a)anthracene, both known carcinogens. Additionally, around one half (46 wt %) of the test material has not been characterized with respect to chemical composition. These are important considerations since skin contact is a likely route of exposure for plant workers. It will also be important to consider additional toxicological testing as the technology progresses toward commercialization. This should include likely routes of exposure (probably dermal and inhalation) and end points such as neurotoxicity, reproductive effects, and teratogenicity. At the moment it seems that the product should be classified as a class 8 (corrosive) product. To make a final classification, all required tests should be done according to relevant transport regulations, referring to UN Manual of Tests and Criteria, OECD test, and others as applicable. It also appears that the variations between different products could lead to different classifications. It is the duty of each bio-oil producer to prove that the classification suggested in this paper is valid also for their product. For bio-oils, there is no UN number assigned at the moment. If further testing shows that the properties for bio-oils are mostly the same, it may be possible to suggest a new UN number for the product. This suggestion should be made to UN, normally by a competent authority, or an association. Suggestion for transport classification (material safety data sheet, Section 14 Transport Information): UN NUMBER: 3265, PROPER SHIPPING NAME: CORROSIVE LIQUID, ACIDIC, ORGANIC, NOS (contains x, y *), CLASS: 8, PACKING GROUP: III, ENVIRONMENTAL HAZARDS: NO. It is the oil producer's responsibility to show that their biooil meets same classification as shown here. More research is needed on material testing using a standard or well proven method, and relevant test conditions are needed.

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AUTHOR INFORMATION

Corresponding Author

*E-mail: anja.oasmaa@vtt.fi. Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS IEA Bioenergy Task 34 Pyrolysis members are acknowledged for their contribution. EU Biotox project NNE5-2001-00744 is acknowledged for providing toxicological data. Risto Markkula from DGM (Dangerous Goods Management Finland Oy) Finland is acknowledged for transportation guidelines and reviewing this paper. Kimmo Kaukanen from VTT Expert Services Ltd. is acknowledged for sustained combustion tests. At VTT, Eeva Kuoppala and Jaana Korhonen are acknowledged for analyses. Tekes, VTT, Metso, UPM, and Fortum are acknowledged for funding.

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REFERENCES

(1) Oasmaa, A.; Peacocke, C. A guide to physical property characterisation of biomass-derived fast pyrolysis liquids. A guide; VTT Publications: Espoo, Finland, 2010; VTT Vol. 731. http://www.vtt.fi/ inf/pdf/publications/2010/P731.pdf. 3872

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(26) Markkula, R. Evaluation of transport classification for fast pyrolysis oils (requested by VTT Finland); Dangerous Goods Management Finland Oy: Finland, 2012. (27) Mohan, D.; Pittman, C. U., Jr.; Steele, P. H. Pyrolysis of wood/ biomass for bio-oil: a critical review. Energy Fuels 2006, 20 (3), 848− 889.

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