以制苯抽余油为溶剂的丁二烯聚合

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。     

Acetone as a selective solvent for vegetable oils

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.     

Isopropanol as a solvent for extraction of cottonseed oil

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.     

Separation of thiophen from benzene by solvent extraction. I

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.     

Separation of thiophen from benzene by solvent extraction. II

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.     

萃取精馏法回收苯和环己烷的溶剂研究

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。     

Isopropyl alcohol as a solvent for free fatty acid titration

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.     

Compressed isobutane as a solvent of heavy hydrocarbons

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     

无水硫酸钙部分替代钛白粉的应用

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%。     

N-methyl-2-pyrrolidone as a solvent for poly(vinyl alcohol)

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.     

Replacement of carcinogenic solvent HMPA by DMI in insect sex pheromone synthesis

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.     

The concept of solid solvent as a processing aid

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.     

Diesel fuel as a solvent for the lipase-catalyzed alcoholysis of triglycerides and phosphatidylcholine

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.     

Dimethyl sulphoxide as a solvent for amylose in the determination of amylolytic activity

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.     

A solid solvent as processing aid for polystyrene

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.     

Polyelectrolytes as secondary calibration standards for aqueous size-exclusion chromatography

The effect of the ionic strength of the solvent on the size-exclusion chromatography of narrow molecular weight dextrans and monodisperse sodium polystyrene sulfonates has been investigated. In both NaOH and NaCl solutions the elution volume of the sodium polystyrene sulfonates increased as the ionic strength was increased, while the elution volume of the dextrans decreased slightly as the ionic strength was increased. The elution data for various ionic strength solvents could not be described by the traditional universal calibration procedure of plotting the product of the intrinsic viscosity and the molecular weight vs. the elution volume. By using a modified calibration procedure which includes excluded volume effects, the elution data can be described for NaOH solution of moderate and high ionic strength. This modified calibration technique was unable to describe the elution data for very low ionic strength NaOH solutions and for the NaCl solutions. Possible explanations of the inability of straightforward size exclusion chromatographic calibration techniques to quantitatively described all the observed elution behavior are discussed.     

Selection of a solvent for adductive crystallization

A procedure for screening solvents for adductive crystallization by use of the data on the enthalpy changes on complex formation, which can be easily measured experimentally, is proposed. Two parameters chemical theory of Harris and Prausnitz has been utilized for calculations of activity coefficients and selectivity values. This method of screening solvents for adductive crystallization seems to be useful for practical applications.     

Natural Palm Olein Polyol as a Replacement for Polyether Polyols in Viscoelastic Polyurethane Foam

The impact of replacing three polyether polyols with different levels of a single palm olein‐based natural oil polyol (NOP) was systematically correlated with the changes in foaming reactivity, cell structure, physico‐mechanical properties, and morphology of viscoelastic (VE) foams. The data show that replacing the polyether polyols with the NOP slightly increased the rate of the foaming reactivity. Increasing the NOP content resulted in increased cell size and cells remained fully open. Increased NOP content contributed to higher load bearing properties of VE foam, which can be attributed to higher functionality of NOP compared to polyether polyols. Addition of the NOP slightly increased the resilience of the foams, however, the hysteresis which is the measure of energy absorption remained mostly unaffected. Age properties, characterized by dry and humid compression sets, were mostly unaffected by the replacement of the polyether polyol with the NOP. The addition of NOP did not impact the morphology of the VE foam polymer matrix, which appears to retain a low degree of hard and soft segment domain separation. Overall, the results demonstrate a feasibility that the NOP can be used to partially replace the polyether polyols in VE polyurethane foams without significant impact on the functional performance.     

Commercial polymer films as calibration standards for EIS measurements

The current protocol regarding calibration and troubleshooting of potentiostats used to conduct electrochemical impedance spectroscopy (EIS) measurements on coated metals involves dummy cells made of simple electrical components. This concept has two major limitations: first, the instrument is used at an impedance range it has not been calibrated for—the instrument is calibrated for impedances in the order of ohms, but corrosion protective coatings usually have impedance values in the range of GΩ cm² or higher; second, commercial coating systems do rarely behave like ideal equivalent circuits of electronic components. In view of these limitations, we propose the use of thin polymer films such as PVF or poly ethylene terephthalate (PET) as new calibration standards for EIS measurements. These films are well defined in thickness and composition and give a highly reproducible response when subjected to EIS measurements. In addition, they closely mimic commercial coating systems with regard to target impedance range and electrical characteristics.