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1.
用Ni-Al-B作催化剂,以制苯抽余油作溶剂,在100mL小瓶和5L反应釜中进行了丁二烯聚合,并在相同条件下与重整抽余油为溶剂的实验结果进行了对比。  相似文献   

2.
Summary It has been shown that useful fractionations of soyabean and linseed oils can be made, using a selective solvent consisting of 3 to 7 parts of water per 100 parts acetone. Equilibrium diagrams were determined for soybean oil, using 3.5 and 6 parts water per 100 parts acetone, and for linseed, using 5 parts water per 100 parts acetone. Operation of a packed column, 2-in. in diameter, 20 ft. high, showed that consistent H.E.T.S. values were obtained, using the above diagrams, and gave an average H.E.T.S. of 3.1 ft. for 1/4-in. berl saddles and 5.9 ft. for 1/2-in. raschig rings. The use of the equilibrium diagrams is illustrated by application to a hypothetical separation. Presented at fall meeting, American Oil Chemists' Society, Minneapolis, Minn., Oct. 11–13, 1954. Issued as Paper No. 190 on the “Uses of Plant Products” and as N.R.C. No. 3627.  相似文献   

3.
Phase equilibrium data for the system; cottonseed oil-isopropanol-water were determined at 30°C. and compared with data for the system; cottonseed oilethanol-water. The relative phase distribution of fatty acids and cottonseed oil in mixtures with isopropanol and water was studied under varying conditions of water and fatty acid concentrations. These tests showed the fatty acids to be highly concentrated in the alcohol-water phase. Flaked cottonseed meats were extracted in continuous extraction apparatus with 91% isopropanol, 99% isopropanol, and mixtures of commercial hexane and isopropanol. Analytical data on the extractions show that 91% isopropanol is an efficient solvent for extracting active gossypol along with the oil. Rat and swine feeding tests of the isopropanol extracted meal showed it to be highly superior to hydraulic meal as a source of protein. A method was developed for treatment of the cottonseed-isopropanol miscella by liquid-liquid extraction to separate purified oil and fatty acid fractions from other materials in the extract.  相似文献   

4.
Fluorinated alcohols are claimed to be promising solvents for supercritical drying. A number of metal oxide aerogels (both monoliths and powders) including silica, alumina and zirconia were prepared using hexafluoroisopropyl alcohol. It is shown that the specific surface area of all the aerogels dried in hexafluoroisopropyl alcohol is twice that of the aerogels prepared in ethanol. Surface modification of aerogels with fluorinated organic species is shown to take place upon supercritical drying.  相似文献   

5.
《Fuel》1987,66(11):1556-1557
The applicability of coal tar pitch as a high-boiling mixed solvent for polymers was studied. Coal tar pitch was heated with different polymers, and the residues were analysed.  相似文献   

6.
Phase equilibrium data are presented for thiophen and benzene distributed between n-heptane and ‘Sulpholane’, dimethyl sulphoxide and dimethyl formamide. They are used to evaluate the possibility of employing distribution between these solvents as a means of separating a mixture of thiophen and benzene.  相似文献   

7.
Phase equilibrium data for thiophen and benzene with water and ‘Sulpholane’, dimethyl sulphoxide (DMSO) and dimethyl formamide (DMF) are presented and used to evaluate the possibility of using aqueous solutions of these solvents to separate small amounts of thiophen from benzene.  相似文献   

8.
本文讨论了用萃取精馏法从油田轻烃中回收环己烷的工艺过程,并以某油田6号溶剂油为研究对象,利用无限稀释条件下的选择因数S∞,为从某油田6号溶剂油中回收苯和环己烷的萃取精馏工艺选择了适宜的溶剂NMP,最后,应用NRTL方程预测了某油田轻烃中的关键组分,在溶剂作用下的相对挥发度的变化情况。  相似文献   

9.
George H. Kyser of Barrow-Agee Laboratories, Inc., Cairo, Illinois, suggested the possibility of using Isopropyl Alcohol as a substitute for Specially Denatured Alcohol, Formula No. 30, in the titration of free fatty acids in crude oil and in the oil of cottonseed samples. This substitution would eliminate the necessity of special permits and bonds for the use of alcohol. Isopropyl Alcohol and cotonseed oil are miscible in all proportions, thus simplifying the titration without the use of violent shaking. Isopropyl Alcohol, with the indicator, is added direct to the oil in the titrating flask and the titration made simply by a twirling motion of the flask. A series of comparative results indicate a very close agreement between titrations, using both Specially Denatured Alcohol and Isopropyl Alcohol as solvents. The author suggests that a committee make further study and recommendations on the use of Isopropyl Alcohol as a solvent.  相似文献   

10.
Large-scale production of microstructured carbon by benzene pyrolysis at 900 °C has been investigated using a quartz plug flow reactor. It was found that a significant increase in carbon yield was achieved by filling the quartz reactor with porcelain tiles. Contrary to what is normally reported in the literature, both lamellar and spherical carbon, characterized by different morphologies and interlayer spacings, was obtained. Considerations about the carbon growth mechanism indicated that the formation of different carbon structures mainly depends on the environment in which the carbon spheres are nucleated.  相似文献   

11.
This research provides solubility data required for environmental applications involving the extraction of heavy hydrocarbons with compressed gases. Dibenzothiophene (DBT), 2‐nitrophenyl disulfide (NPDS), and tetramethylthiuram disulfide (TTDS) have been selected as model compounds for this type of pollutants and isobutane as compressed gas. The solubilities obtained at 367–413 K and 3.9–7.5 MPa, expressed as solute mole fractions, were in the ranges 0.025–0.106 for DBT, 1.2 × 10?4?6.3 × 10?4 for NPDS, and between 2.7 × 10?4 and 1.8 × 10?3 for TTDS. They were compared to other pollutants solubilities (anthracene and carbazole). From the comparison, the following solubility order was established: DBT > anthracene > carbazole > TTDS > NPDS. Furthermore, when comparing these isobutane solubilities to those in propane and CO2, they were found to be about one and two magnitude orders larger, respectively. Results obtained were explained considering solvent density, solute vapor pressure, and interactions between solutes and solvent. Peng–Robinson equation was used to correlate the data and a good fitting attained. © 2016 American Institute of Chemical Engineers AIChE J, 62: 2870–2878, 2016  相似文献   

12.
目前钛白粉的价格居高不下,而且在国内钛复合颜料的研究尚处于起步阶段。钛白粉具有很多优势,但是其昂贵的价格让人们不得不考虑采用其他的产品来替代钛白粉。为了节省昂贵的钛白粉,降低成本,长期以来人们都积极地研究和开发利用高效价廉的体质颜料取代钛白粉,研究新的产品部分替代钛白粉势在必行。由于硫酸钙具有良好的白度以及胶凝性,故可部分替代钛白粉添加到涂料中,最大替代量为钛白粉用量的20%。  相似文献   

13.
The concept of solid solvent entails the use of low-molecular weight crystalline materials (LMC) as a processing aid. A LMC as an ideal solid solvent mixed into a polymer is expected to become a solvent for the polymer at high processing temperatures, reducing the melt viscosity and thus enhancing the processability, but to become a nonsolvent for the polymer at low use temperatures precipitating out of the polymer without adversely affecting the properties of the polymer. The feasibility of such a concept was examined using acetanilide as a potential solid solvent for polystyrene (PS) and two ABA-type block copolymers containing PS end blocks. Acetanilide demonstrated the essential features required of a solid solvent supporting the concept of solid solvent. It had a high solubility in PS at high temperatures very effectively reducing the melt viscosity of PS and the block copolymers, and it precipitated out of PS at low temperatures although it had an undesirably high residual solubility. The concept of solid solvent appears to be a viable one.  相似文献   

14.
NMP (N-methyl-2-pyrrolidone) and its mixtures with water have been investigated as solvents for PVA [poly(vinyl alcohol)]. Judging from the higher exponent in the Mark-Houwink equation, NMP appears to be a better solvent than water. The equation found is for solutions in NMP at 30°C. Although the viscosity of NMP–water mixtures goes through a maximum when the molar ratio of NMP to water is 1:2, the intrinsic viscosity for PVA exhibits neither a maximum nor a minimum in mixtures ranging from pure water to pure NMP. As in aqueous solutions, the intrinsic viscosity in NMP solutions decreases slightly with increasing temperatures from 20 to 50°C.  相似文献   

15.
Amylose readily dissolves in dimethyl sulphoxide (DMSO) to give clear colourless solution which is stable and forms a convenient stock amylose solution for amylase determinations. Dimethyl sulphoxide has no inhibitory effect on different amylolytic enzymes at the concentrations required for enzyme assay.  相似文献   

16.
The abilities of three commercially available lipases—Lipozyme IM 20, Amano PS-30, and Amano CE—to synthesize fatty acid ethyl esters via the alcoholysis of soy triglycerides (TG) and phosphatidylcholine (PC) in grade No. 2 diesel fuel were investigated. All three enzyme preparations were active in water-saturated diesel fuel, synthesizing fatty acid esters from both TG and PC. Response surface methodology, based on a Modified Central Composite design, was employed to examine the coordinate effects of lipid, water, and ethanol concentrations on enzyme activities and to identify conditions yielding maximum alcoholysis. For all three enzymes, optimal activities toward TG occurred at added water concentrations of less than 0.3 M. With PC as substrate, optimal enzyme activities occurred at added water concentrations as much as tenfold greater than this, and the amount of water required for maximum activity was proportional to the substrate concentration. For both substrates the enzyme activities were generally reduced as ethanol concentrations rose. The exceptions to this were the Lipozyme-TG combination, where activity increased with increasing ethanol concentrations, and the PS-30-PC combination, where activity was roughly constant across the range of water and ethanol concentrations examined. Hydrolytic activities of the enzymes in aqueous reactions were poor predictors of transesterification activity in organic solvent: the aqueous hydrolytic activities of CE and PS-30 toward TG were roughly comparable, and 25 to 50 times greater than that of IM 20. However, in the alcoholysis of TG in diesel fuel the order of activities was PS-30>IM 20>CE. The activities of Lipozyme and CE toward PC were similar to one another, and PS-30 was considerably less active on this substrate. CE lipase was more active toward PC than toward TG. Lipozyme displayed comparable activity toward the two substrates. PS-30 was considerably more active on TG than on PC. Degrees of conversion were consistent with the transesterification of only one fatty acid of TG, and slightly greater than one fatty acid for PC. Preliminary studies indicated that for CE and PS-30, but not for Lipozyme IM 20, the degree of conversion of TG, but not PC, could be significantly increased by the further provision of ethanol. Expansion of this work could lead to a method for the production of simple fatty acid esters, which are suitable as diesel fuels, from multicomponent agricultural materials containing TG and PC.  相似文献   

17.
A novel PMoV-paired ionic polymer was prepared by anion-exchange of a newly task-specific designed carboxylic acid-functionalized ionic polymer with a Keggin V-containing heteropolyacid, and characterized by FT-IR, SEM, TG, XRD, 1H NMR, and CNH elemental analysis. Its catalytic performance for hydroxylation of benzene with H2O2 was studied using CH3CN as solvent. The obtained polymer is revealed to be a highly efficient heterogeneous catalyst for hydroxylation of benzene, showing a high yield to phenol 26.9% with 100% selectivity. The solid catalyst has a convenient recoverability with a considerable catalyst recovery rate of above 90%, and the reused catalyst in the fourth run showed a phenol yield of 17.8%.  相似文献   

18.
Hexamethylphosphoric triamide (HMPA) is a good solvent for the alkylation of terminal acetylenes; however, it has been proven to be a carcinogen towards rats and should be considered as a serious risk to man when a large-scale synthesis is involved. Thus the search for a safe alternative is important. The physical properties of 1,3-dimethyl-2-imidazolidinone (DMI) are similar to DMPU (1,3-dimethyl-2-oxo-hexahydropyrimidine) and HMPA, but the potential toxicological risk of DMI is less than DMPU and HMPA. When used in the alkylation of terminal acetylenes, DMI is comparable with HMPA, thus it is a good alternative solvent to the carcinogen HMPA in the alkylation because it provides a safer working environment than DMPU and HMPA.  相似文献   

19.
Many polymers suffer from excessive heat generation during processing due to high viscosity, and reduction of viscosity is desired to control the melt temperature during processing. The concept of solid solvent was recently proposed based on thermally reversible compatibility between a polymer-additive pair. Benzenesulfonamide was found to be virtually a perfect solid solvent for polystyrene, and this finding clearly proves that solid solvents can be used as processing aid for polymers to effectively reduce the viscosity.  相似文献   

20.
Rapid and facile screening techniques to determine the effectiveness of solvents for cellulose or biomass dissolution can advance biomass processing research. Here, we report the use of a simple optical microscopy method to screen potential cellulose and lignin solvents. The described methodology was used to screen the dissolution of cellulose and lignin in two imidazolium‐based ionic liquids (ILs), two phosphonium‐based ILs, as well as a N,N‐dimethylacetamide/lithium chloride (DMAc/LiCl) solution in less time than other techniques. The imidazolium‐based ILs and the DMAc/LiCl were found to dissolve both cellulose and lignin. Also, it was observed that one of the phosphonium‐based ILs dissolved lignin and not cellulose, demonstrating a potential for biomass fractionation applications. © 2011 Canadian Society for Chemical Engineering  相似文献   

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