Ind. Eng. Chern. Res. 1993,32, 1710-1716
1710
GENERAL RESEARCH Surfactant Based on Aromatic Extract Sulfonate Abou El Naga H. Hamdi, Abdel Azim M. Wedad,' Sideros K. Naguib, and Awad G. Nader Research Centre and Chemical Sector, Misr Petroleum Co., P.O. Box 228, Cairo, Egypt
Aromatic extracts, which are accumulated through the refining of lubricating oils, are purified. Gas chromatographic analysis showed that they have several diverse components, while their structure group analysis showed their suitability for sulfonation and formulation of heavy-duty liquids. The purification method here is based on dewaxing the saturates from the aromatic extract components and treating the remaining components with active clay to remove the polyaromatics and other different resins. Sulfonation conditions for these extracts, in the presence of butyl acetate as a capturing agent, were adjusted to optimize the product yield. The isolated sulfonic acid was neutralized by adding 50 % sodium hydroxide solution. Heavy-duty liquids were formulated by dissolving the obtained sodium sulfonates together with nonionic surfactant with a chemical structure based on ethylene oxide-octylphenol condensates as a foam promoter. Urea was also incorporated as a solubilizing agent. Formulated heavy-duty liquids have shown high detergency power, good emulsification, and low wetting power. Generally, they can be recommended for heavy-duty applications. 1. Introduction The lubricating oil fractions obtained from crude oils by vacuum distillation contain aromatic components, which are undesirable since they oxidize in engines to sludge-forming compounds and, moreover, have poor viscosity/temperature properties. In the manufacture of high-grade lubricating oils, therefore, it is necessary to remove these aromatic compounds, which can be done by solvent extraction.l The disposal of aromatic extracts which are gathered from solvent extraction processes sometimes imposes serious problems and complications for the refineries throughout handling, transporting, and/ or storage, or even in dumping them. Some refineries have developed some techniques for the utilization and upgrading of aromatic extracts. Parts of these residues are used as extender oils for natural and synthetic carbon blacks. Faracasiu et examined the transalkylationtechnique, where new distallableproducts of small aromatic molecules and substituted normal alkyl, iso-alkyl, and cycloalkyl groups can be synthesised from aromatic extracts. A1 Sammerrai and Barbooti3 evaluated aromatic extract as oxidation inhibitors for sulfur-free and sulfur-containing refined lubricating oils. Aromatic extracts are rich in all types of aromatic compounds,e.g., mono-,di-, andpolyaromatics. Therefore, pure aromatic extracts are expected to be easily sulfonated to give good starting materials for formulation of surfaceactive agents. Aromatic extracts as received from refineries contain different impurities, e.g., resines, asphaltenes, and sulfur compounds. Therefore, the establishment of a reliable purification method can greatly help in using these extracts for synthesis of surfactants. The main target of the present work is to upgrade these aromatic extracts, which are dealt with as having very low economic value, into suitable and valuable formulated heavy-duty liquids. Therefore, this work is proposed to proceed in the following steps:
1. Evaluate the suitability of the chemical structure of available local aromatic extracts as starting materials to synthesize aromatic extract sulfonates. 2. Find a proper and reliable purification method in order to remove undesirable impurities from aromatic extracts. 3. Establish optimum sulfonation conditions for purified aromatic extracts. 4. Formulate heavy-duty liquids by using the synthesized aromatic extract sulfonates. 5. Measure and evaluate performance characteristics for formulated heavy-duty liquids in comparison to commercially available surfactats.
2. Experimental Section Physical and chemical properties of light, medium and, heavy aromatic extract samples (LA-1,MA-1, MA-2, and HA-2) as received from local refineries were analyzed via standard routine methods according to IP and ASTM test methods as well as via nonroutine methods. Table I includesthe obtained results. The fine chemical structure for two samples (MA-2 and HA-2) were evaluated via gas chromatography (GC).Figures 1 and 2 represent the obtained chromatograms. A purification method was developed to treat the aromatic extract samples. This method is based on dewaxing of the saturate components and then treating the remaining components by active clay to remove heterocyclic and resin compounds. Operating conditions for this method are as follows: 1. The aromatic extract sample is dewaxed by dissolving it at a 1:l ratio in a mixture of 5 methyl ethyl ketone (MEK):3 toluene:2 hexane. The mixture is then filtered at 0 "C under circulation to separate the saturate components. 2. About 500 g of the filtrate (the remaining aromatic component and resins) is added to 10 mL of hexane and then warmed to 50 "C with stirring until it is completely
0888-588519312632-1710$04.Oo/O 0 1993 American Chemical Society
Ind. Eng. Chem. Res., Vol. 32, No. 8,1993 1711 Table I. General Properties and Chemical Classes of the Aromatic Extract Samples As Received and After Purification LA-1 MA-1 MA-2 HA-2 general properties before after before after before after before after ~p gr 60/60 O F (ASTM D-1298) 0.9508 0.9498 0.9728 0.9650 0.9970 0.9202 1.0015 0.9979 38.79 36.36 79.26 60.49 371.3 34.22 1170 240.9 kinet vis. a t 40 OC. cSt (ASTM D-445) 4.92 6.24 4.83 6.72 13.75 4.99 kinet vis. at 100 O C , cSt (ASTM D-445) 23.5 15.84 6 12 21 12 6 15 21 24 pour point, "C (ASTM D-97) 2.11 3.14 3.0 2.5 3.58 4.41 3.42 sulfur, wt % (ASTM D-129) 2.3 0.1 0.2 0.12 0.1 0.3 0.2 0.3 asphaltene, wt % (ASTM D-893) 0.1 63 60 65 sulfonatable content,a wt % 55 hydrocarbon classes,' wt % 24.3 6.0 20.5 6.15 22.3 6.32 saturates 19.6 5.9 22.4 51.1 45.5 8.5 44.00 19.3 monoaromatics 9.5 40.0 18.5 23.1 24.1 38.3 33.5 37.25 diaromatics 30.7 42.0 34.8 11.1 45.1 11.38 9.7 12.1 37.1 polyaromatics and resins 40.2 75.7 77.7 93.68 94.0 93.85 94.1 79.5 80.4 total aromatics structural group' analysis 27.12 14.26 9.2 26.7 CA % 67.37 48.46 49.3 69.2 CP % 5.51 41.5 4.1 37.28 CN % Nonroutine test method.
13
F l a m e Ionization Detector (F.1.D.) Flow 2 0 m l / m i n Column OV-17
Solvent
CHC13
I
4 1
t I
I
I
1
1
I
I
I
400
500
6 00
700
800
9 00
1000 16:40
1100
6:40
1o:oo
13:20
id00
1ioo
Temp.(OF)
2000
21:f.O
ScanTime
Figure 1. Chromatogram of medium aromatic extract (sample MA-2).
homogeneous. About 20% by weight activated clay is added to this mixture at 80-100 "C with stirring for 2 h. Clay activation is obtained by heating it for 3 h at 120 "C. The treated sample is filtered at high temperature under 4-bar pressure to eliminate the resins and polyaromatics. The physical and chemical properties for the purified aromatic extract samples are listed in Table I. Hydrocarbon group analysis of the aromatic extracts, either as received or after purification, was carried out on a chromatographic column4which is dry-packed with 440 g of fully activated F-20 alumina gel in the bottom half and 310 g of fully activated grade 12 Davison silica gel in the top half. The column is prewet with n-hexane, and an amount of acid-base and neutral nitrogen-free sample containing no more than 1g of aromatic per 100 g of gel (usually 10-25 g of sample) is charged to it. The four compound-typefractions-saturates, monoaromatics, diaromatics and polyaromatics-are eluted with the solvent sequence according to the following table:
fraction tm
eluent
mL
n-hexane n-hexane 5 % benzene n-hexane 15% benzene methanol + 20% benzene + 20% ether methanol
2500 3000 3000
~~
saturates monoaromatics diaromatics polyaromatics
+ +
500
1000
Solvents are running in the column at a flow rate of approximately 200 mL h-l. Each fraction can be collected either in total by the use of a continuous solvent stripper attached to the bottom of the column or in small subfractionswhich are individuallyanalyzed by measuring the refractive index of the eluate at 20 "C. hydrocarbon class type saturates mono and diaromatics polyaromatics and resins
refractive index limits 4.48 1.48-1.59 >1.59
Infrared spectra6 for the purified aromatic extract samples were carried out using a Perkin-Elmer 598 infrared spectrophotometer with a data processor.
1712 Ind. Eng. Chem. Res., Vol. 32, No. 8,1993
10
Flame Ionization Detector (F.I.D.)
Flow 20 mllmin. Column OV-17 Solvent
I
CHC13
8 b
7
$1 1
I
I
I
I
I
200
400
6 00
8 00
3:3 0
7:OO
1030
14:OO
1000 17:30
12 00 21:OO
I \ 1400 24:30
TemR (OF) Scan Time
Figure 2. Chromatogram of heavy aromatic extract (sample HA-2). Table 11. Applied Optimum Sulfonation Conditions sulfonating agent sample no. acid/sample ratio concentrated sulfuric acid
fuming sulfuric acid (oleum)
LA-1 MA-1 MA-2 HA-2 LA-1 MA-1 MA-2 HA-2
1.6:l 1.7:l 1.7:l 1.7:l 1.51 1.5:l 1.5:l 1.5:l
Sulfonatable contents6 for the purified aromatic extract samples were determined where 20-25 g of the sulfonated sample is added to 50 mL of industrial methylated spirt (IMS), which is composed of 85% ethyl alcohol, 10% methyl alcohol, and 5% distilled water. The mixture is shaken vigorously for 1/2 h in a separating funnel until the sample is dispersed. The IMS layer is separated, and an additional amount of 25 mL of IMS mixture is added to the sample. The mixture is shaken vigorously for an additional 1/2h and the IMS layer is separated. The previous step is repeated .several times until the extracted IMS layer becomes clear. The collected IMS layers are washed further with 50 mL of 30-40" petroleum spirit and shaken gently for 1 min. The IMS solution is allowed to separate and the petroleum spirit layer (upper layer) is rejected; the IMS layer is filtered through a cotton wool plug. Then the solution is evaporated on a steam bath until all the IMS is removed. Finally the residue weight is determined. The sulfonatable content of the sample is calculated by means of the following equation: reacted org mater content (wt % ) = mass of residue in g X 100 mass of sample in g Table I includes the obtained results of hydrocarbon group, infrared spectral analyses, and sulfonatable contents. Sulfonation of aromatic extract was carried out in a three-neck round-bottom flask equipped with a mechanical stirrer, a dropping funnel, and a temperature control device. Many sulfonation attempts were conducted with the aim of establishing optimum conditions, i.e., conditions
capturing agent
reaction temp, OC
butyl acetate butyl acetate butyl acetate butyl acetate butyl acetate butyl acetate butyl acetate butyl acetate
35-45 35-45 35-45 40-50 35-45 35-45 35-45 35-45
digestion time, h 5
5-6 5-6 5-6 3 4-5 4-5 5-6
yield, w t % 65 60 60 52 70 65 65 55
which gave the maximum yield of sulfonatable products. These optimum sulfonation conditions were listed in Table 11. Either concentrated or fuming sulfuric acid was used as sulfonating agent. n-Butyl acetate was added first as a capturing agent to the purified aromatic extract. The role of the capturing agent was to stop any sulfonation reactions. Sulfonation reaction was carried out under mild stirring at temperature in the range 35-50 "C. After complete addition of the sulfonating agent, the reaction mixture was stirred at the same temperature range for 3-6 h as a digestion time. The resulting sulfonic acid was then separated by further addition of ethyl alcohol. Separated sulfonic acid was neutralized by adding 50% aqueous sodium hydroxide solution. Formulated heavyduty liquids were prepared from the sodium sulfonates by dissolving them in water together with nonionic surfactant (ethylene oxide-octylphenol condensates) as a foam promoter. Urea was also incorporated in these formulations as a cheap solubilizing agent. Physical properties of formulated heavy-duty liquids were measured according to standard test methods (cf. Table 111). The detergency test,' Draves wetting test,"1° emulsification test,ll and Ross-Miles foam testI2 were carried out on the solutions of the formulated heavy-duty liquids with 0.2,0.4,0.8, and 1.0 wt % water as follows. 2.1. Determination of Detergency Power.' Small test pieces (5 X 5 cm) of the soiled fabrics (standard soiled cotton) were washed in 250 mL of the formulated heavyduty liquid solutions a t 60 "C for 30 min by using a Tergotometer apparatus, which consists of a set of four mechanicalagitators. Fabrics were removed, washed with distilled water, and dried a t 75 "C. The reflectance of
Ind. Eng. Chem. Res., Vol. 32, No. 8, 1993 1713 Table 111. Physical and Chemical Properties of the Formulated Surfactants 1,2,3, and 4 Compared with Commercial Surfactant (SI specification anionicactive matter, w t % total active matter, wt % pHof0.1 wt % cloudpoint,"C
testmethod S 1 ASTMD-1681 11.7 7.2
2 7.1
3 10.1
Table V. Foam Volume and Stability for the Formulated Surfactants ~
4 8.1
sampleno.
S
ASTMD-1172 20.5 14.4 14.3 18.96 15.14 ASTMD-1172 7.5 ASTMD-97 -1
8.7 18
8.9 19
8.1 9
Table IV. Surface Activity for the Formulated Surfactants surfactant concentration (wt performance property no. 0.2 0.4 0.8 detergency power, % S 29.1 44.5 63.5 1 40 70 82 2 45.5 82 90 3 60.2 75.5 87.5 4 62.5 77.5 90.7 wetting time, s S 55 35 5 1 164 84 70 2 184 110 85 3 219 113 89 4 1100 450 200 emulsification power, % S 60 61.7 64.8 1 50 50 50 2 48. 48.5 50.5 3 45 46.2 49.7 4 45 46 49.5
8.9 11
1
2 %) 1.0 69.7 88 92 90.1 92.5 4 52 64 64 155 66.7 50 51 51.8 52.8
light for each piece of the washed fabrics was measured using a Hunterlab Model D25-2 color difference meter. The reflectance was compared to magnesium oxide disk reflectance (standard value 100). The detergency power was then calculated using the Kublka-Moank equation: detergency power = Rw - R , x 100 Rc - R, where R, is the reflectance of the washed fabric, R, is the reflectance of the soiled fabric, and R, is the reflectance of the cleaned fabric. 2.2. Determination of the Wetting Power.819 The wetting power was determined by measuring the time in seconds needed for complete sinking of a standard gray cotton yarn of 5-cm length in a solution of the formulated heavy-duty liquid at 25 "C as described by Draves.lo 2.3. Determination of the Emulsification Power.l1 The emulsification power was determined by vigorously stirring an equal volume of solution of the formulated heavy-duty liquid with a flushing oil for 30 min at 25 "C. The solutions were left to stand for 24 h, and the depth of the oil emulsion was measured. The results are expressed as percent emulsion. 2.4. Determination of Ross-Miles Foam.12 One hundred milliliters of the solution of the formulated heavyduty liquid was vigorously shaken several times in a 250mL stoppered graded cylinder, and the volume of the resulting foam was measured. The half-lifeof the produced foam is taken as a measure for the stability of the foam by measuring the foam volume after 10 min. Results of detergency, wetting, and emulsification powers are listed in Table IV, while Ross-Miles foam results are listed in Table V.
3. Results and Discussion 3.1. Molecular Structure. Separation of medium and heavy aromatic extracts into their chemical components was accomplished by GC. Figures 1and 2 represent the chromatograms of MA-2 sample and HA-2 sample, re-
3
4
concn, wt %
foam vol, cma
foam vol, after 10 min, cms
0.2 0.4 0.8 1.0 0.2 0.4 0.8 1.0 0.2 0.4 0.8 1.0 0.2 0.4 0.8 1.0 0.2 0.4 0.8 1.0
70 80 110 120 70 90 110 120 60 70 100 120 50 60 70 80 50 60 75 85
40 70
80
110 50 70 80
stabilitv good
good
90 25 40 50 60 15 20 30 35 15 25 35 40
moderate
low
low
spectively,Figure 1of MA-2 sample shows that this sample contains about 20 components; these components which exist in different proportions are the only ones traced via the applied GC technique. 3.2. Physical and Chemical Properties of Aromatic Extracts. Physical and chemical properties of aromatic extract samples as recived from local refineries are listed in Table I. These results show that aromatic extract samples LA-1 and MA-1 (from refinery 1) have lower specific gravity, viscosity, pour point, flash point, sulfur content, and asphaltene percentage than those of samples MA-2 and HA-2 (from refinery 2). These differences may be due to the use of different crudes in these two refineries: refinery 1is using low paraffinic crudes, while refinery 2 is using high paraffinic crudes. Increase of paraffinic content of the crude naturally increases the flash point, pour point, and viscosity index. Accordingly, aromatic extract samples from refinery 2 show much higher values than those from refinery 1, especially for MA-2 sample in comparison with MA-1 sample. The comparison between physical and chemical properties of aromatic extract samples as received and after purification indicates that purification results in the decrease of asphaltene values for purified samples. Reductions in these properties for samples MA-2 are more pronounced than in the case of samples LA-1 and MA-1, which may be also attributed to the differences between their crudes. 3.3. Hydrocarbon Classes. Table I includes the results of the hydrocarbon classesfor the aromatic extracts before and after their purification. Generally, it is clear that light aromatic extract LA-1 has the highest weight percent saturates. On the other hand, the heavy aromatic extract HA-2 has the lowest saturate percentage. LA-1 and MA-1 have nearly the same saturate contents, while MA-2 and HA-2 have also nearly equal saturate contents; this may be attributed to the fact that the crude of LA-1 and MA-1 is the same, while MA-2 is from another crude. Comparison between the results of column separation of aromatic extract samples before and after purification shows that equal reduction in both saturates and polyaromatics (about 70-75 % ) for all samples occurred. Generally, these resultsj indicate that the applied purification method has a good efficiency in reducing the undesirable and unsulfonatable components. 3.4. Structure Group Analysis. It is clear from Table I, which includes also the obtained results of the structural
1714 Ind. Eng. Chem. Res., Vol. 32, No. 8, 1993
group analysis for purified samples, that samples MA-2 and HA-2 have the highest value in CA%. This can be attributed to their source of crude which is highly parafiiic, while LA-1 and MA-1 are from another crude type with lower paraffinc content. Although it is expected that aromatic extracts must have low Cp % and high CA%,Cp % for all aromatic extracts has the higher values. This may be due to the substitution in their aromatic nuclei with long side chains which are determined as Cp and not as CA. 3.5. SulfonatableContents. The comparison between the sulfonatable contents of the purified aromatic extract samples, as listed in Table I, and of both their hydrocarbon classes and their structural group analysis showed that although MA-2 and HA-2 have higher CA%values than those for LA-1 and MA-1, they have lower sulfonatable contents. On the other hand, it is clear that MA-2 has the lowest weight percent monoaromatics, while LA-1 has the highest value, but MA-1 and MA-2 are nearly similar. Accordingly, weight percent monoaromatics can be considered as agood parameter for sulfonatable content rather than CA%. Generally, the results of sulfonatable content show that the aromatic extract samples have good to moderate values, which indicate their suitability for sulfonation processes. 3.6. Sulfonation. Two different sulfonation processes were applied to the purified aromatic extract samples LA1, MA-1, MA-2, and HA-2 by using either concentrated or fuming sulfuric acids as sulfonating agents. Mechanism of sulfonation using concentrated HzS04 as a sulfonating agent is as follows:
The mechanism in the case of using fuming HzS04 as a sulfonating agent is as follows: R
e +
so3
intertmlecular
R
e
o
,
-
-
R e S O 3 H 2 '
The sulfonation attempts which were applied to each of the aromatic extract samples gave very low yields of sulfonic acids even with long digestion time. This was attributed to the probability of the presence of alcoholic and phenolic groups which led to occurring of sulfation according to the following mechanism: +H+
H,SO, + H20' - SOZOH
ROH + -H20
-H+
RHO' - S0,OH + ROS0,OH Butyl acetate was added as a capturing agent during the sulfonation to increase the rate of sulfonation by decreasing the rate of sulfation reaction. From the
optimum sulfonation conditions, as listed in Table 11, the following can be decided: 1. Optimum sulfonation conditions for both samples MA-1 and MA-2 are nearly the same, whether concentrated HzS04 or fuming HzSO4 waa used. 2. Both samples MA-1 and MA-2 give a moderate percent of sulfonation product. This may be attributed to the presence of long chains attached to their aromatic nuclei which hindered the proceeding processes. This can be noticed from Cp% values in Table I. 3. Optimum sulfonation conditions for sample LA-1 require the lowest reaction temperature and shortest digestion time, and give the highest yield of sulfonation product. This may be due to the chemical structure of its components, since it has the highest weight percent monoaromatic content. 4. The lowest yield of sulfonation products with sample HA-2 may be due to the diversity in its structure, in addition to having the lowest weight percent monoaromatic content. 5. Generally, optimum sulfonation conditions for all samples using fuming HzS04 require a lower reaction temperature and shorter digestion time than those using concentrated HzSO4. On the other hand, these conditions give higher yields of sulfonation products. 3.7. Evaluation of the Formulated Heavy-Duty Liquids. The sulfonic acids produced were neutralized with 50 7% sodium hydroxide solution. Heavy-duty liquids were formulated by using sodium aromatic extract sulfonate, ethylene oxide-octylphenol condensates as a nonionic surfactant, ureaas a solubilizingagent, and water with ratio 12:3:5:80 (wt %). Formulated heavy-duty liquids from sodium sulfonates of aromatic extract samples LA1, MA-1, MA-2, and HA-2 are numbered 1, 2, 3, and 4, respectively. Table I11 illustrates the physical and chemical analyses of the formulated heavy-duty liquids and a commercial one (S; trade name Misrol 410, manufactured by Misr Petroleum Co.) which consists of linear sodium alkylbenzenesulfonate, the same nonionic surfactant, urea and water with ratio 12:3:5:80 (wt 7%). From this table the following could be noticed 1. Generally, the total active matter of formulated heavy-duty liquids (1,2,3, and 4) is within the same range, which is lower than that of commerical ones, except 1, which is nearer to that of S. 2. The anionic active matter of formulated heavy-duty liquid 1is intermediate between those of formulated heavyduty liquids 2-4 and the commercial one (S),but 1is more similar to S than to the others. 3. Cloud points of 1-4 and the pH of their 0.1 wt % solutions are higher than that of S. This may be due to the differences between the natures of their chemical structures. Formula 1 (formulated from LA-1) has properties more like those of the commercial one (S),while the others (2-4) (formulated from MA-1, MA-2, and HA2) have properties more different from those of S. This means that aromatic extract LA-1 is more suitable for sulfonation. 4. On the other hand, the others (MA-1, MA-2, and HA-2) are less suitable for sulfonation. This may be due to the presence of bulky groups in the benzene ring of their components which may be restricting their sulfonatability, (cf. Table I, hydrocarbon classes and structural group analysis). Results of detergency, wetting, and emulsification powers, are listed in Table IV. Ross-Miles foam results, at concentrations 0.2, 0.4, and 0.8, 1 w t 5% in water, are
Ind. Eng. Chem. Res., Vol. 32, No. 8,1993 1715
L
loot-
68
90
:: L\
a
s E
80
70 60
>
50 W
a
E
40,
W
0
-
30-
10
0.2
0.4
0.6
0.8
1.0
C0NC.j % W t .
Figure 3. Relationship between detergency power and detergent concentration. 250
t
0.2
!
0.4
0.6
0.8
1.0
CON C . j '10W t
.
Figure 5. Relationship betweenemulsification power and detergent concentration. 120
-
110
-
100m
E 0
Y
90
-
ao -
I 70-I
0
> I
2 0.2 0.4
0.6 0.8
1.0
CONC.1 % Wt.
6050-
LL
Figure 4. Relationship between wetting power and detergent concentration.
listed in Table V, while Figures 3, 4, 5, and 6 show the relationship of detergency, wetting, emulsification powers, and foam volume against the detergent concentration compared with those of the commercial one (SI. These results indicate, as expected, that detergency, wetting emulsification powers, and foam volume increase with the increase of formulated heavy-duty liquid concentration. All formulated heavy-duty liquids give excellent values of detergency power compared with that of the commercial one S. On the other hand, they show poor wetting power. This may be due to the long side chains in their components. Emulsification power for all formulated heavy-duty liquids is moderate, but formula 4 (formulated from HA2) has a relatively higher emulsification power. This may be due to the presence of more components with longer side chains in aromatic extract sample HA-2 than in the other aromatic extract samples. From the results of Table V we notice that formulated
-
401
10
0.2
01,
0.6
0.8
1.0
CONC.1 % W t .
Figure 6. Relationship between foam volume and detergent concentration.
heavy-duty liquid 1 gives almost the same foam volume as the commercial one (SIwith the same foam stability a t the same concentrations. Formulated heavy-duty liquid 2 gives a moderate foam volume with moderate foam stability. Formulated heavy-duty liquids 3 and 4 give low foam volume and low foam stability in comparison to the commercial one (S). All this may be due to more long side chains in the components of MA-2 and HA-2 than those existing in the components of LA-1 and MA-1.
1716 Ind. Eng. Chem. Res., Vol. 32,No. 8, 1993
4. Conclusion Structural group analysis of light, medium, and heavy aromatic extracts from the lubricating oil solvent extraction process shows that these extracts are suitable for sulfonation and formulation of heavy-duty liquids. Optimum sulfonation conditions are as follows: concentrated or fuming sulfuric acid at ratio 1.5,1.6, and 1.7 to 1 part of the sample; sulfonation temperature 35-50 "C,digestion time 3-6 h. A capturing agent (butyl acetate) must be added during the sulfonation reaction to control the reaction rate. Formulated heavy-duty liquids give good detergency power; therefore, they are suitable for using as heavyduty soil cleaners in industrial sites and also as oils and grease removers in petroleum service stations. Literature Cited (1) Royal Dutch/Shell Group of companies. Solvent extraction. In The Petroleum Handbook, 6th ed.; Elsevier: Amsterdam, 1983; Chapter 5. (2)Faracasiu;et al. Presented at the symposiumon New Chemistry of Heavy Ends. Division of Petroleum Chemistry, 190th National Meeting of the American Chemical Society, Chicago, IL, September 1985.
(3) Al-Sammerrai, D. A.; Barbooti, M. M. Evaluation of Aromatic Extracts as Antioxidants for Mineral Oils. Am. Chem. SOC.1985. (4) Altgelt, K.H.; et al. Separation Schemes. In Chromatography in Analysis; Marcel Dekker: New York and Basel, 1979;Vol. 11, Chapter 9. (5)Brandea, G. Structural Groups of Petroleum Fraction. Brennst. Chem. 1956,37,263. (6) Shell InternationalPetroleumCo."ShellMethod Series;"1964; SMS 1404-4. (7) Petroleum products and Lubricants. In Annual Book of ASTM Standards; ASTM Philadelphia, 1975; Part 30, ASTM D-1568Dp 236. (8) McCutcheon, J. W. M. Synthetic Detergents; Mac Nair Dorland: New York, 1950. (9) Harris, J. C. Detergent Evaluation and Testing, 6th ed.; Interscience: New York, 1963; Chapter 2. (10)Dravee, C. Z. Am. Dyest. Rep. 1939,28,425. In Surfactants and Interfacial Phenomena; Miltom J. R., Ed.; Wiley-Interscience: New York, 1978;Chapter 6. (11) Camp, M. C.; Durhami, K. J. Phys. Chem. 1955,59,993. (12)SB Board of Consultants & Engineers. Analysis of Finished Detergents. In The Testing & Analysis of Synthetic Detergents; SBP Chemical Engineering Series 40; 1980; Section D, 76.
Received for review June 30, 1992 Revised manuscript received March 25, 1993 Accepted April 8, 1993
