Catalytic Cracking of C2âC3 Carbonyls with Vacuum Gas Oil

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Catalytic Cracking of C2-C3 Carbonyls with Vacuum Gas Oil Desavath V. Naik, Vimal Kumar, Basheshwar Prasad, Babita Behera, Neeraj Atheya, Dr. D. K. Adhikari, Nigam Krishna D. P., and Madhukar Omkarnath Garg Ind. Eng. Chem. Res., Just Accepted Manuscript • Publication Date (Web): 17 Jun 2014 Downloaded from http://pubs.acs.org on June 19, 2014

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Industrial & Engineering Chemistry Research

Catalytic Cracking of C2-C3 Carbonyls with Vacuum Gas Oil Desavath V. Naikb, Vimal Kumara, Basheshwar Prasada, Babita Beherab, Neeraj Atheyab, Dilip K. Adhikarib, Nigam K.D.Pc*,1 Madhukar O. Gargb a

Department of Chemical Engineering, Indian Institute of Technology Roorkee-247667, India b

c

Bio-fuels Division, CSIR-Indian Institute of Petroleum Dehradun-248005, India

Department of Chemical Engineering, Indian Institute of Technology Delhi-110016, India

Abstract Fluid catalytic cracking (FCC) route could be considered for the co-processing of biomassderived pyrolysis oil with petroleum-derived vacuum gas oil in a typical refinery unit by integrating it with biomass fast pyrolysis process. This paper aims to study the effect of coprocessing of pyrolysis oil representative model compounds (C2-C3 carbonyls such as hydroxyacetone and glycolaldehyde dimer) with vacuum gas oil (VGO) in a FCC Advanced Cracking Evaluation (ACE-R) unit, using industrially available fluid catalytic cracking equilibrium catalyst (E-CAT). The blending ratios of C2-C3 carbonyls and VGO were varied from 5:95, 10:90, 15:85 and 20:80. The reactor was operated in close to industrial FCC process at 530 0C temperature and atmospheric pressure with catalyst-to-oil ratio of 5.0. The blended FCC feedstock and their liquid distillates were structurally characterized by 1H, and gated decoupled

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C NMR techniques. The average structural parameters like branchiness index,

substitution index, average length of alkyl chains, and fraction of aromaticity per molecule was obtained from NMR data. A linear increase in FCC conversion was observed with increase in hydroxyacetone blending ratio with VGO from 5 to 20%, which may be due to increase in

*1 Corresponding author: Email - [email protected] 1 ACS Paragon Plus Environment


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propylene and decrease in heavy cycle oil. The increase of glycolaldehyde blending ratio from 5 to 10% increased the FCC conversion; whereas decreased the conversion at 15 and 20% ratios. The 1H and 13C NMR data indicated that there is an increase in mono-aromatics with increase in hydroxyacetone; whereas in the case of glycolaldehyde the mono-aromatics increased for blending ratio upto 10% and decreased on further increase in blending ratios. The equilibrium FCC catalyst is capable of cracking oxygenates presents in pyrolysis oil like hydroxyacetone and glycolaldehyde towards the production of liquefied petroleum gas range products. Further a scheme has been proposed for processing of pyrolysis oil in petroleum refinery units.

Keywords: Fast pyrolysis, Pyolysis-oil, Fluid catalytic cracking, Co-processing, NMR, Carbonyls

1. Introduction The biomass is considered as one of the realistic source for renewable transport fuel [1] which is necessary for sustainable development [2]. It can be converted into crude bio-oil or pyrolysis oil by conventional thermo-chemical conversion routes. The obtained pyrolysis oil can be further upgraded through hydrodexoygenation or catalytic cracking to produce liquid or gaseous hydrocarbons. The FCC process for co-processing of biomass-derived pyrolysis oil with vacuum gas oil is becoming an attractive option for the production of liquid hydrocarbons (gasoline and diesel) and olefins based petrochemical feedstock. The FCC process is the heart of petroleum refinery for converting heavy molecular weight hydrocarbons into gasoline with a limited processing cost [3]. In this regard pyrolysis technology for the production of pyrolysis oil has been validated at a pilot level [4]; whereas the approach for co-processing of pyrolysis oil in

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refinery perspective is at research level. The difference in properties between highly polar pyrolysis liquid and a typical aliphatic fluid catalytic cracking feed is significant and poses a real challenge for co-processing of pyrolysis oil in refinery FCC unit [5]. Therefore, there is a need to carry out an extensive research on co-processing of pyrolysis oil model compounds as well as pyrolysis oil with refinery feedstock in FCC unit. The pyrolysis oil is formed by thermal or catalytic decomposition of biomass containing cellulose, hemicellulose and lignin. The variation in composition of pyrolysis oil is depends on several factors such as type of lignocellulosic biomass (source, structural composition and inorganics present), type of pyrolyzer, operating conditions (such as pyrolysis temperature and pressure), oil recovery system, and catalyst used at various stages. Pyrolysis oil consists of large number of organic compounds including acids, ketones, aldehydes, alcohols, esters, sugars, phenols, phenol derivatives and lignin-derived oligomers etc., [6]. The fraction of hydroxyacetone and glycolaldehyde in biomass-derived pyrolysis oil varies from 0.7 to 7.4 wt.% [7] and from 5 to 13 wt.%, respectively [7, 8]. Glycolaldehyde is seen as a second major product after levoglucosan even on fast hydropyrolysis of cellulose at 500 0C temperature [9]. Each compound of pyrolysis oil has its own cracking chemistry for obtaining product slate of fluid catalytic cracking process while co-processing with VGO. In this view preliminary investigations were carried out by Gayubo et al. [10, 11] and Bakhshi et al. [12–16]. It was reported that there was coke formation during the processing of pyrolytic oil oxygenated compounds over zeolite catalyst in isothermal fixed bed reactor at temperature less than 410 ˚C, which follows the following order: phenol or aldehyde > acetone or acetic acid > alcohols. Graca et al. [17, 18] studied the co-processing of pyrolysis oil model compounds such as acetic acid, phenol, guaiacol and acetol with vacuum gas oil in FCC approach. Higher coke 3 ACS Paragon Plus Environment


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formation was reported by Naik et al. [19] on catalytic cracking of guaiacol with VGO. Further, the presence of phenol and benzene was also reported in the liquid product. Samolada et al. [20] reported 50% increase in coke yield on addition of 15 wt.% of hydrotreated flash pyrolysis oil (FPO), a heavy fraction, with light cycle oil (LCO). They reported that the gasoline yield does not vary significantly by changing either the catalyst types or the catalyst–to– oil ratio. For co-processing of HDO oil with VGO, similar yields for gasoline and LCO were reported by Fogassy et al. [21]. Thegarid et al. [22] carried out the co-processing of HDO oils with VGO and catalytic pyrolytic oil (CPO) with VGO and reported an increase in coke, olefins, aromatics, and alkyl phenols. The production of alkyl phenols was more in case of co-processing of CPO/VGO as compared to HDO/VGO. In the present work an effort has been made to understand the effect of pyrolysis oil representative C2-C3 carbonyls (e.g. hydroxyacetone or acetol and glycolaldehyde) on coprocessing with vacuum gas oil (VGO) in FCC advanced cracking evaluation unit by varying blending ratio from 5 to 20%. In addition to the product distribution pattern, the aromaticity patterns, using 1H and 13C NMR spectroscopy techniques, have also been investigated.

2. Material and methods 2.1 Material The co-processing of VGO with C2-C3 carbonyls was carried out with an equilibrium industrial FCC catalyst (E-CAT). Equilibrium catalyst (E-CAT) is consists of synthetic faujasite zeolite (USY or REUSY), matrix (silica-alumina), clay (e.g. Kaolin clay) with binder and special additives (i.e., NOx reduction additives, gasoline sulfur reduction additives, CO combustion


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promoters, ZSM-5 as an additive for the production of light olefins). The characteristics of ECAT used in the present work are listed in Table 1. The commercially available petroleumderived vacuum gas oil (VGO) was used and its characteristics are shown in Table 2. Hydroxyacetone (assay 90%, Sigma-Aldrich Chemicals) and glycolaldehyde dimer (SigmaAldrich Chemicals) were selected as C2-C3 carbonyls of pyrolysis oil, respectively. The mixture of hydroxyacetone with VGO and glycolaldehyde with VGO were denoted as VGO+HA and VGO+GA, respectively.

2.2 Fluid catalytic cracking The catalytic cracking experiments were carried out using an advanced cracking evaluation (ACETM) unit supplied by M/s Kayser Technologies Inc., USA. The schematic diagram of ACE unit is shown in Figure 1. The ACE-R unit was equipped with an automated fixed-fluidized bed reactor, which is widely accepted in the petroleum refinery for fluid catalytic cracking catalyst evaluation studies. The cracking was performed by varying the blending ratio of C2-C3 carbonyls to VGO from 5 to 20% at a constant catalyst-to-oil (C/O) ratio (i.e., 5%), atmospheric pressure and 530 ˚C temperature. The catalyst amount was kept constant during all the experiments, i.e.9 g.

The catalyst was stripped off by nitrogen several times, i.e. for a period of 7 times of injection time. During the catalytic cracking and stripping, the liquid product was collected in a glass receiver, maintained at -10 ˚C temperature, which is located at the end of the reactor exit. Meanwhile, the gaseous products were collected in a gas receiver by water displacement. After cracking and stripping steps the reactor was operated in regeneration mode, where the coke



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deposited on the catalyst surface during the cracking reaction was burnt off with air at a temperature of 700 °C. The flue gases generated during regeneration process were sent to the catalytic converter/furnace packed with cuprous oxide, where carbon monoxide was converted into carbon dioxide at 540 °C temperature. The step of regeneration process/mode was continued till the amount of carbon dioxide formation reduced to zero in the flue gases. The reactor effluent gases are on-line measured and these values are used to estimate the amount of carbon deposited on E-CAT during cracking (i.e., coke formation).

2.3 Analysis The liquid samples were analyzed on Agilent 6890 gas chromatography equipped with ASTM D-2887 system according to their boiling point range. The boiling point range distribution for liquid samples are as follows: gasoline (IBP-216 0C), light cycle oil (216–370 0C), and heavy cycle oil (> 370 0C). The conversion is defined as the sum of the product yields of dry gas, LPG, gasoline and coke as per MAT conversion in refineries.

The product gases were analyzed using a Varian CP-3800 gas chromatography equipped with three detectors, a flame ionization detector (FID) for C1 to C5 hydrocarbons, and two thermal conductivity detectors for analysis of hydrogen and nitrogen. The coke deposited on the catalyst was burnt with air in regeneration mode and the resulted carbon dioxide was analyzed using IR spectroscopy (1440 Servomex).

Solution state 1H-NMR spectra (in CDCl3) were recorded on 11.7T Bruker AVANCE III spectrometer, which was operated at 500 MHz resonance frequency using a 5 mm BBFO probe.


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The conventional 1H-NMR experiments were carried out using 5% w/v sample solution in CDCl3 (99.8%, Aldrich) with 64 number of scans, a π/2 pulse length of 13.4 µs, 10s recycle delay, 64K time domain data. Quantitative 13C NMR spectra were acquired using approx 70 mg oil dissolved in 450 µl of CDCl3 employing an inverse gated decoupling sequence with proton 90˚ pulse of 13.4 us, and relaxation delay of 5s. The FID is exponentially multiplied and Fourier transformed with 0.3 Hz and 1 Hz apodization for 1H and 13C and referenced to TMS at 0 ppm. Before starting the analysis, the spectra obtained were corrected for phase and baseline and then each of them were separated into different regions that correspond to different types of protons and carbons according to their position in the molecule. Later, each spectrum was integrated thrice and averaged within the indicated regions.

3. Results and Discussion 3.1 Co-processing of hydroxyacetone with VGO The co–processing of pyrolysis oil model compound, i.e. hydroxyacetone (C3H6O2), with petroleum-derived vacuum gas oil was carried out at different blending ratios, which was varied from 5 to 20%. Figure 2 shows the conversion of VGO and yields of dry gas, LPG, gasoline, LCO, HCO, Coke, Propylene, C3 paraffin/olefin ratio, and CO2 on varying the blending ratios. The conversion of VGO with hydroxyacetone for different blending ratios is shown in Figure 2a. From Figure 2a it can be seen that the presence of acetol increased the conversion from 68 to 78% with increase in blending ratio. It may be due to the increase in the yield of liquefied petroleum gas from 21 to 47 wt.% (Figure 2c), which is at the cost of decrease in yield of gasoline (Figure 2d) from 39 to 23 wt.% followed by light cycle oil (Figure 2e) from 18 to 12 wt.% and heavy cycle oil (Figure 2f) from 11 to 7 wt.%, respectively. From our previous study 7 ACS Paragon Plus Environment


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[19], it was found that on catalytic cracking of VGO at C/O ratio of 5 and 530 °C temperature, the yield of gasoline was found to be 44 %, which is considered to be optimum; whereas the presence of acetol with VGO results in decrease in hydrogen content of the feed and thereby the gasoline yield and conversion across the FCC unit was further decreased. The decrease in gasoline yield may be due to decrease in hydrogen content of feedstock on adding acetol with VGO in FCC unit, and is considered as over-cracking of gasoline. From Figure 2c it can be seen that the yield of LPG increases linearly with increase in blending ratio. However, the increase in olefins may not be due to only the over cracking of gasoline, but it is also due to low hydrogen transfer reactions. Higher paraffin-to-olefin ratio is an indicator of secondary hydrogen transfer reactions [23]. Figure 2h shows that with increase in acetol blending ratio the C3 paraffin-to-olefin ratio was decreased from 0.28 to 0.16. It indicates that the amount of secondary hydrogen transfer reactions reduced, which lead to decrease in the gasoline yield and increase in propylene yield (Figure 2i), which was also confirmed from the coke yield analysis. From Figure 2g it can be seen that the presence of acetol reduced the coke formation as compared to pure VGO catalytic cracking over FCC equilibrium catalyst at constant C/O ratio of 5. Further it was observed that the coke formation decreased with increase in acetol, in VGO, during catalytic cracking. However, in case of catalytic cracking of raw pyrolysis oil over FCC catalyst results in heavy coking [24]. Further, it was also observed that the yield of carbon dioxide (Figure 2j) increase with increase in blending ratio, which clearly indicates the decarboxylation reaction. In addition for the purpose of reproducibility and regeneration studies, the regenerated catalyst was used three times in a series to carry out the same set of experiments with both feeds at C/O


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ratio of 5 and blending ratio of 5. The yields of FCC products were observed within the range of ±4% error. 3.2 Co-processing of glycolaldehyde with VGO The conversion and yields of various FCC product on co-processing of glycolaldehyde dimer with vacuum gas oil in advanced cracking evaluation unit by varying the blending ratio from 5 to 20% is shown in Figure 2. From Figure 2a it can be seen that the conversion increased from 69 to 75% with increase in the blending ratio from 5 to 10%; whereas beyond that the conversion decreased to 65% for the blending ratio of 20%. The yield of dry gas (Figure 2b) and liquefied petroleum gas yield (Figure 2c) first increased from 1.8 to 2.4 wt.% and 35 to 43 wt.%, respectively, with increase in blending ratio from 5 to 10%; and on further increase in blending ratio to 20% the yields of dry gases and LPG decreased to 1.8 and 27 wt.%, respectively. Further, it was observed that the gasoline yield (Figure 2d) first decreased from 27 to 25 wt.%, and then increased to 32 wt.% with increase in blending ratio. Figure 2e shows that the light cycle oil yield first decreased from 17 to 15 wt.% and then increased to 20 wt.%; whereas the yield of heavy cycle oil (Figure 2f) first decreased from 11 to 9wt.%, and then increased to 13 wt.% with increase in blending ratio from 5 to 10%. The yield of ethylene and propylene also followed the same trend with increase in blending ratio of glycolaldehyde upto 10% blending, and there on the yields were decreased with further increase in blending ratio. The change in the product profiles during catalytic cracking of VGO with more than 10% glycolaldehyde may be due the fact that the glycolaldehyde, an acetaldehyde, has low reactivity to hydrocarbons and attributes mainly to oligomerization products with noticeable coke formation. The present findings are in good agreement with the work of Gayubo et al. [11].



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Gayubo et al. [11] carried out the catalytic cracking of acetaldehyde up to 450 °C temperature over HZSM5 catalyst in an isothermal fixed bed reactor and reported that with increase in blending beyond 10%, there is an increase in liquid hydrocarbons which may be due to the formation of oligomerized products. Figure 2g shows that the coke yield decreased from 4.5 to 4.25wt.% with increase in blending ratio from 5 to 10%; and thereon it increased to 4.29 wt.% for higher blending ratio (20 wt.%). The increase of coke formation may be due to the increase in poly-aromatics formation beyond 10% blending ratio. Similar results were found from nuclear magnetic resonance (NMR) spectroscopy analysis. The poly-aromatics formation initially decreased from 1.95 to 0.59; thereon it increased to 3.15 with increase in blending ratio. NMR analysis indicated that the mono- and di-aromatics first increased with increase in blending ratio from 5 to 10% and then decreased on further increase in blending ratio upto 20%. 3.3 NMR Characterization The average structural parameters of FCC liquid samples after catalytic cracking were analyzed by NMR spectroscopy techniques. From the resulting spectra, Figures 3 and 4, a series of average structural parameters were derived, which allowed the liquid samples to be characterized and compared on the basis of blended components by varying blending ratios. The results can only be considered approximate, since they present an over-simplified picture of very complex mixtures containing a wide range of components. However, the method described has the advantage that the few spectra can be obtained on crude material without preliminary treatment. The average structural information is derived from the integral of NMR spectra to the structural specificity of the hydrogen and carbon type distribution with associated chemical shift regions.


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The chemical shift regions are as follows: protons and carbons of aromatics (6.0−9.0 ppm, and 110-150ppm), hydroxyls (3.5−6.0 ppm and 60-110 ppm), and aliphatics (0.5−3.5 ppm and 5-60 ppm). The structural parameters of liquid samples are shown in Table 3. Figure 3(a-d) shows 1H and Figure 3(e-h) shows

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C NMR spectra of liquid samples obtained

from catalytic cracking of hydroxyacetone with VGO. Although the spectra look similar, however, their quantitative information derived is varies. Analysis of NMR results showed that the fraction of aromaticity (fa) decreased from 0.54 to 0.46 with increase in blending ratio of hydroxyacetone from 5 to 15%; whereas an increase of fa observed at 20% blending ratio. The fraction of aromaticity (fa) here is the percentage of aromatic to the total carbons. The substitution index calculated from the ratio of substituted aromatic carbon to total aromatic carbons, which indicates that the aromatics on blending of 10% of acetol are heavily substituted followed by 20, 15 and 5% of acetol. The branchiness index shows a decrease in branching of alkyl chains with blending. The condensation index derived from ratio of bridgehead aromatic to total protonated aromatic carbons, and it was observed that the aromatics from 20% blending are least condensed. The NMR spectroscopy analysis indicated that mono-aromatics decreased from 14.63 to 9.89 while the poly-aromatics increased from 0.1 to 0.81 with increase in blending ratio of acetol from 5 to 20% with vacuum gas oil. Although the blending component in both cases containing oxygenates, the product shows the absence of oxygenated protons and carbons which indicated that the oxygen is removed in the form of gaseous fraction. From Figure 3 it can be seen that there is no sharp peak for oxygenated proton in the chemical shift region of 3.5-6 ppm and carbon in the chemical shift region of 60-110 ppm and > 160ppm), respectively. Hence, it is believed that the liquid products on catalytic cracking of VGO with acetol and glycolaldehyde



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are free from oxygenates and the quality of FCC distillate is as same as conventional one which matches the gasoline RON/MON and diesel cetane index. Figures 4(a-d) and 4(e-h) show the 1H and

13

C NMR spectra of liquid samples, respectively,

obtained from catalytic cracking of glycolaldehyde dimer with VGO. In this case the spectra obtained were similar as in case of acetol with VGO. However, their quantitative information derived was different. From the NMR analysis it was observed that the aromaticity is higher at lower blending ratio of 5%. The substitution index, which indicates degree of substitution to aromatics, is lower for 10% blending ratio. The branchiness index is higher for 10% and 20% blended distillates followed by 15 and 5% blended cracked distillate. The condensation index shows that the 10 and 15% derived liquids are equally condensed, which suggest similar nature of aromatics. On the basis of other results in collaboration with NMR product analysis, the 10% blended glycoldehyde can be considered as optimum. The average chain length of alkyl chain in the distillate was found to be 3. Higher percentage of mono-aromatic protons can be selfexplanation for lower substitution index as well as low percentage of substituted aromatic carbon with highly branched alkyl chain, with 10% glycolaldehyde loading. 4.

Proposed Scheme for Processing of Pyrolysis Oil in Refinery Units

Several options have been pointed out by various research groups for the effective use of refinery infrastructure for biomass-derived fast pyrolysis oil upgrading into liquid hydrocarbons. In this regard, a case study of direct-integration of biomass (i.e. bagasse based) fast pyrolysis process with refinery was carried out [25-26]. From their analysis it can be said that this route allows the direct addition of fast pyrolysis oil in existing refineries catalytic cracking units and the option is relatively cheap and also helps to increase the profitability of current low margins of refineries.


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Further, it is mentioned that in spite of oxygen presence, a high intensity of aromatic content is reported in diesel cut of hydrotreated pyrolysis oil, which mismatches the specifications of petroleum-derived diesel fuels [27]. At this point of time, further cracking is very much essential to convert it into acceptable diesel blend form using the hydrocracker facility of refinery, which may be a more viable option. Furthermore, this type of option is more viable in countries like India, where the demand of diesel cut is extremely high. It also helps the refineries with a safe and secured domestic feedstock source. Based on the present results and our previous work [19] for the co-processing of pyrolysis oil model compounds (such as acetic acid, 2-methoxy phenol, hydroxyacetone and glycoldehyde dimer) with vacuum gas oil in FCC unit, it has been observed that the aliphatic oxygenates are easily crackable in FCC process at lower blending ratios; whereas the aromatic hydrocarbons are not easily cracked. Therefore, it is proposed to first separate the aliphatic and aromatic oxygenates from the pyrolysis oil either by solvent extraction or other techniques. Accordingly, an approach for processing of pyrolysis oil in refinery units is proposed in Figure 5. This kind of approach may help petroleum refineries to integrate it with fast pyrolysis process to increase the yield of liquefied petroleum gas and also the valuable and most demanded petrochemical feedstock i.e propylene.

5. Conclusions In the present work the effect of C2-C3 carbonyls on the co-processing of VGO with fast pyrolysis oil on FCC product distribution was investigated. It was observed that the acetol can be co-processed with VGO upto the blending ratio of 5:95 without major changes in the original



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FCC product slate; beyond that the LPG range products were increased. From the cracking of the mixture of glycolaldehyde dimer with vacuum gas oil in fluid catalytic cracking unit, it was found that the results are in agreement with the NMR spectroscopic analysis. It was concluded that there is a limit for co-processing of glycolaldehyde with VGO refinery fluid catalytic cracking unit due to the increase in poly-aromatics formation. It is very much needed to improve the ability of FCC catalyst towards higher hydrogen transfer reactions (by adding more rare earths) to stop the over cracking of liquid products if the blending is carried out beyond 5%. In other way, there is great scope to improve the yield of LPG by co-processing of hydroxy-acetone with VGO. Further, the hydroxyacetone can be separated from fast pyrolysis oil for coprocessing in refinery FCC units to obtain better yields of liquefied petroleum gases. Accordingly a scheme has been proposed for the processing of pyrolysis oil in petroleum refinery units.

Acknowledgement All authors thank to the analytical science division of CSIR-Indian Institute of Petroleum for the characterization of FCC products.

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11. Gayubo, A.G.; Aguayo, A.T.; Atutxa, A.; Aguado, R.; Olazar, M.; Bilbao, J. Transformation of Oxygenate Components of Biomass Pyrolysis Oil on a HZSM-5 Zeolite. II. Aldehydes, Ketones, and Acids. Ind. Eng. Chem. Res.2004, 43, 2619-2626. 12. Adjaye, J.D.; Bakhshi, N.N.. Production of hydrocarbons by catalytic upgrading of a fast pyrolysis bio-oil. Part II: Comparative catalyst performance and reaction pathways. Fuel Process. Technol. 1995, 45, 185−202. 13. Adjaye, J.D.; Bakhshi, N.N. Production of hydrocarbons by catalytic upgrading of a fast pyrolysis bio-oil .Part 1. Conversion over various catalysts. Fuel Process. Technol. 1995, 45, 161-183. 14. Adjaye, J.D.; Katikaneni, S.P.R.; Bakhshi, N.N.

Catalytic conversion of a bio-fuel to

hydrocarbons: effect of mixtures of HZSM-5 and silica-alumina catalysts on product distribution. Fuel Process. Technol. 1996, 48, 115-143. 15. Sharma, R.K.; Bakhshi, N.N., 1993. Catalytic upgrading of pyrolysis oil. Energy Fuels. 1993, 7, 306-314. 16. Srinivas, S.T.; Dalai, A.K.; Bakhshi, N.N. Thermal and catalytic upgrading of a biomassderived oil in a dual reaction system. Can. J. Chem. Eng 2000, 78, 343. 17. Graça, I.; Ribeiro F.R.; Cerqueira, H.S.; Lam, Y.L.; de Almeida, M.B.B. Catalytic cracking of mixtures of model bio-oil compounds and gasoil. Appl. Catal. B: Environ.2009, 90, 556– 563. 18. Graça, I.; Lopes, J.M.; Ribeiro, M.F.; Ribeiro,F.R.; Cerqueira,H.S.; de Almeida, M.B.B. Catalytic cracking in the presence of guaiacol. Applied Catalysis B: Environmental 2011,101, 3–4, 613–621.


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19. Naik, D.V.; Kumar, V.; Prasad, B.; Behara, B.; Atheya, N.; Singh, K.K.; Adhikari, D.K.; Garg, M.O. Catalytic cracking of pyrolysis oil oxygenates (aliphatic and aromatic) with vacuum

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26. Jones, S.B.; Holladay, J.E.; Valkenburg, C.; Stevens, D.J.; Walton, C.W.; Kinchin, C.; Elliot, D.C.; Czernik, S. Production of gasoline and diesel from biomass via fast pyrolysis, hydrotreating and hydrocracking: A design case. PNNL Report No-18284, US Department of Energy, February 2009.


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List of Figures

Figure 1: Schematic diagram of advanced cracking evaluation (ACE-R) FCC unit Figure 2: Effect of blending ratio of C2-C3 carbonyls with VGO on FCC conversion and product yields:(a) FCC conversion, (b) dry gas, (c) LPG, (d) Gasoline, (e) LCO, (f) HCO, (g) Coke, (h) ethylene, (i) propylene, and (j) CO2. Figure 3: 1H (a-d) and 13C (e-h) NMR spectra of liquid sample obtained from catalytic cracking of VGO with hydroxyacetone Figure 4: 1H (a-d) and 13C (e-h) NMR spectra of liquid sample obtained from catalytic cracking of VGO with glycolaldehyde dimer Figure 5: Proposed approach for the processing of pyrolysis oil in refinery units

List of Tables

Table 1: Physicochemical characteristics of E-CAT Table 2: Characterization of vacuum gas oil Table 3: NMR derived average structural parameters of liquid samples



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Table 1: Physicochemical characteristics of E-CAT Properties

E-CAT

SiO2 (wt.%)

39.05

Al2O3 (wt.%)

20.8

Na2O (wt.%)

0.3124

Ni (ppm)

762

V (ppm)

57

Fe (ppm)

4182

Cu (ppm)

459

Surface area (m2/g)

171


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Table 2: Characterization of vacuum gas oil Properties

Vacuum gas oil

Density at15oC, g cc-1

0.919

Kinematic viscosity at 100oC, cSt

10.83

API gravity

22.39

Basic N UOP269, ppm

540

Total N2, wt.%

0.106

Total S, wt.%

0.19

CCR, wt.%

3.64

Asphaltene content, wt.%

2.01

Wax content, wt.%

19.2

IBP

350 0C

10%

369 0C

30%

400 0C

50%

441 0C

70%

489 0C

90%

550 0C

FBP

550 0C

Iron (ppm)

134.7

Vanadium (ppm)

1.1

Nickel (ppm)

4.0

Copper (ppm)

0.43

Zink (ppm)

3.15



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Table 3: NMR derived average structural parameters of liquid samples

VGO HA:VGO

GA:VGO

C/O -5 -5 -5 -5 -5 -5 -5 -5 -5

B.Ratio 100 100 5:95 5:95 10:90 10:90 15:85 15:85 20:80 20:80 5:95 5:95 10:90 10:90 15:85 15:85 20:80 20:80

n 18 6 3 3 3 3 3 3 3 3

fa 0.13 0.48 0.14 0.54 0.14 0.48 0.14 0.46 0.15 0.49 0.12 0.54 0.11 0.49 0.11 0.51 0.12 0.50

Ch 4.90 37.27

Cb 1.36 3.19

ARq 5.70 7.32

BI 0.35 --

SI 0.47 --

45.09

3.57

5.51

36.94

3.81

7.14

0.51 -0.5

37.79

3.41

5.02

40.36

2.14

6.94

0.5 -0.48

10.20 -15.19 -10.91

43.28

3.34

7.21

0.51

13.60

40.41

3.73

4.46

0.56

9.10

40.86

3.71

6.73

0.52

13.19

39.51

3.35

7.27

0.56

14.54

14.16

C/O: Catalyst-to-oil ratio; n: Average chain length; fa: Fraction of aromaticity; Ch: Proton aromatic carbon; Cb: Bridgehead aromatic carbon; ARq: Substituted aromatic carbon; BI: Branchiness Index; SI: Substitution Index; H/Ceff: Effective hydrogen index based on elemental analysis; m-a: Mono-aromatics d-a: Di-aromatics p-a: Poly-aromatics


H/Ceff 1.725 -1.67 -1.62 -1.57 -1.51 -1.64 -1.55 -1.46 -1.38 --

m-a 2.33

d-a 1.6

p-a 0.55

14.63

6.57

--

10.75

5.81

0.11

10.59

5.81

0.25

9.89

6.83

0.81

9.8

8.05

1.95

13.3

6.26

0.59

10.42

7.63

1.49

8.16

8.13

3.15

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N2 Catalyst

Feed Bottle Vent

Syringe Pump Catalytic Converter Condenser

IR Analyzer

Liquid Receiver

Catalyst Receiver

Refinery Gas Analyzer Gas Receiver

N2

Figure 1: Schematic diagram of advanced cracking evaluation (ACE-R) FCC unit.



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(a)

(b)


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(C)

(d) 3 ACS Paragon Plus Environment


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(e)

(f) 4 ACS Paragon Plus Environment

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(g)

(h) 5 ACS Paragon Plus Environment


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(i)

(j)

Figure 2: Effect of blending ratio of C2-C3 carbonyls with VGO on FCC conversion and product yields:(a) FCC conversion, (b) dry gas, (c) LPG, (d) Gasoline, (e) LCO, (f) HCO, (g) Coke, (h) ethylene, (i) propylene, and (j) CO2. 6 ACS Paragon Plus Environment

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Figure 3: 1H (a-d) and 13C(e-h) NMR spectra of liquid sample obtained from catalytic cracking of VGO with hydroxyacetone.



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Figure 4: 1H (a-d) and 13C(e-h) NMR spectra of liquid sample obtained from catalytic cracking of VGO with glycolaldehyde dimer.


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Figure 5: Proposed approach for the processing of pyrolysis oil in refinery units.


Catalytic Cracking of C2âC3 Carbonyls with Vacuum Gas Oil

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