Solubilities and diffusivities of N2O and CO2 in aqueous sulfolane solutions

The solubilities of N₂O and CO₂ in aqueous sulfolane solutions and pure sulfolane solvent, and the diffusivities of N₂O in aqueous sulfolane solutions were measured and correlated over the temperature range from 20° to 85°C; also, the data for density and viscosity that were needed in this experimental work were measured. This experiment revealed that the parameter of N₂O analogy method depends not only on the temperature, but also on the character of the solvent. Therefore, different solvents possess different analogy parameters. Only for dilute aqueous solutions can the parameter be replaced by the analogy parameter of water. The results also proved that the sum of volume fractions contribution is a simple method to estimate the solubility in aqueous sulfolane solutions over the whole range of the concentrations and experimental temperatures, with an average deviation of less than 4·0%.     

以环丁砜为溶剂制备聚丙烯腈纤维的初步研究

环丁砜是一种高沸点、低毒性、强极性的环保溶剂。对以环丁砜为溶剂用干湿法制备的聚丙烯腈(PAN)纤维进行初步研究,得到了断裂强度为3.48 cN/dtex的PAN纤维。结果表明,拉伸倍数的增加使PAN纤维的结晶度结晶取向因子增加,而结晶尺寸出现先升后降的现象,纤维的断裂强度和断裂功的变化与结晶尺寸相似。合理的拉伸倍数有利于得到较好力学性能的纤维。     

二元混合物环丁酚和对二甲苯、乙苯在温度范围为303.15—353.15K下的密度、黏度及其相关性质

Densities and viscosities of the binary systems of sulfolane ＋ ethylbenzene, sulfolane ＋ p-xylene have been experimentally determined in temperature interval 303.15—353.15 K and at atmospheric pressure for the whole composition range. The excess molar volumes and viscosity deviations were computed. The computed quantities have been fitted to Redlich-Kister equation. Excess molar volumes and viscosity deviation show a systematic change with increasing temperature. Two mixtures exhibit negative excess volumes with a minimum which occurs approximately at χ = 0.5. The effect of the size, shape and interaction of components on excess molar volumes and viscosity deviations is discussed.     

二元混合物环丁酚和对二甲苯、乙苯在温度范围为303.15-353.15K下的密度、黏度及其相关性质

Densities and viscosities of the binary systems of sulfolane ethylbenzene, sulfolane p-xylene have been experimentally determined in temperature interval 303.15-353.15 K and at atmospheric pressure for the whole composition range. The excess molar volumes and viscosity deviations were computed. The computed quantities have been fitted to Redlich-Kister equation. Excess molar volumes and viscosity deviation show a systematic change with increasing temperature. Two mixtures exhibit negative excess volumes with a minimum which occurs approximately at x = 0.5. The effect of the size, shape and interaction of components on excess molar volumes and viscosity deviations is discussed.     

环丁砜劣化机理与应对措施研究进展

介绍了近年来国内外对于环丁砜劣化机理的研究情况,以及工业上应对环丁砜劣化所采取的措施。着重介绍了环丁砜热稳定剂的广阔前景,指出目前环丁砜热稳定剂的研究情况和存在的问题,展望了环丁砜热稳定剂的重大应用价值。     

Excess Molar Volumes and Viscosities of Binary Mixtures of p-Xylene with Cyclohexane, n-Heptane, n-Octane, Sulfolane, N-Methyl-2-pyrrolidone and Acetic Acid at 303.15 K and 323.15 K and Atmospheric Pressure

Experimental data on density and viscosity at 303.15 K and 323.15 K are presented for the binary mixtures of p-xylene with cyclohexane, n-heptane, n-octane, sulfolane, N-methyl-S-pyrrolidone and acetic acid. From these data, the excess molar volume and deviations in viscosity have been calculated. The computed quantities have been fitted to the Redlich-Kister Equation to derive coefficients and estimate the standard error values. Results are discussed in terms of intermolecular interactions.     

Solubility of H2S and CO2 in sulfolane

The solubility of H, S and CO₂ in sulfolane (tetrahydrothiophene-1, 1—dioxide) has been measured at 40°C and 100°C at pressures up to 2350 kPa and 5900 kPa respectively. The Henry's constants obtained from the data are in agreement with those of Rivas and Prausnitz.     

Influence of structure and counterions on physicochemical properties of linear alkylbenzene sulfonates

The effects of different inorganic and organic counterions on the physicochemical behavior of three commercial linear alkylbenzene sulfonates (LAS) have been studied. It has been found that the counterion hydration radius of the corresponding commercial linear alkylbenzene sulfonates has great influence on solubility, viscosity, surface tension and critical micelle concentration (CMC). The counterion has no influence on the detergency performance of the finished formulation. The alkyl chain length and the presence of tetralines have an important influence on solubility, viscosity and surface tension.     

Solubility of N2O and CO2 in n-Dodecane

The solubility of CO₂ and N₂O in a physical solvent, n-dodecane [C.A. Registry N° 124–18–5], has been measured at 40, 80 and 120°C at pressures up to 9.6 MPa. The experimental results were correlated by the Peng-Robinson (1976) equation of state, and the interaction parameters, the Henry's constants and the N₂O analogy parameters were obtained.     

Equilibrium solubility of H2S and CO2 and their mixtures in a mixed solvent

The solubility of hydrogen sulphide, carbon dioxide, and their mixtures has been measured at 40° and 100°C in a mixed solvent consisting of 20.9 wt% MDEA (methyldiethanolamine), 30.5 wt% sulfolane (tetrahydrothiophene-1, 1-dioxide), and 48.6 wt% water. The results have been compared with those for aqueous 2.0 mol/dm³ MDEA and an analogous mixed solvent, containing AMP (2-amino-2-methyl-1-propanol), which are available in the literature. These data were used to modify the solubility model of Deshmukh and Mather (1981) to account for the mixed solvent effects on the system thermodynamics. Results show that the model is useful as a first approximation in predicting acid gas solubilities; agreement with experiment was generally found to be within £15%.     

环丁砜萃取精馏提纯连三甲苯的实验和模拟

针对混合C₉芳烃原料中沸点接近、分离困难的连三甲苯-茚满物系,以环丁砜为萃取剂进行了萃取精馏分离提纯实验,并采用Aspen Plus化工流程模拟软件对萃取精馏工艺过程进行了模拟研究,萃取精馏实验数据与模拟结果吻合较好,相对偏差小于5%。结合萃取精馏实验和流程模拟考察了萃取精馏塔的理论塔板数、溶剂比（萃取剂与原料的质量比）、回流比以及原料和萃取剂的进料位置等因素对分离效果的影响规律。结果表明,环丁砜萃取精馏提纯连三甲苯较适宜的工艺条件是：萃取精馏塔的理论塔板数为60~65、溶剂比为5~7、回流比为3~4、原料的进料位置为第34~36块板、萃取剂的进料位置为第8~10块板,在此条件下,塔顶可获得高纯度的连三甲苯产品,其质量分数可达99%以上,回收率可达93%以上。     

环丁砜对乙醇胺溶液吸收和解吸CO2的影响

利用物理溶剂环丁砜替代部分水,采用气液搅拌实验装置和真实热流量热法测定了环丁砜对乙醇胺（MEA）溶液吸收和解吸二氧化碳（CO₂）过程的影响,考察了CO₂循环负载、吸收速率、吸收热和解吸热等性质变化。研究表明：环丁砜对MEA溶液负载CO₂的吸收热影响较小,但对吸收速率、循环吸收容量和解吸过程影响较大。环丁砜可降低MEA溶液对CO₂的表观吸收速率,且随CO₂负载量的增大,降幅也逐渐变大。环丁砜有利于富液解吸过程,加快解吸速率,增大CO₂解吸程度,同时单位热流负荷、单位冷流负荷和单位能耗均有不同程度的降低。在燃煤电厂烟气条件下,20% MEA+20% sulfolane体系相对20% MEA体系,其表观吸收速率平均降低约10%,CO₂循环吸收容量增加24%,单位CO₂解吸能耗降低18%。     

基于氯化钙溶液的混合盐溶液除湿剂物性测量

为了改善单一除湿盐溶液的性能,同时降低耗费成本,越来越多的学者致力于混合除湿盐溶液的研究。考虑以价格低廉但除湿效果一般的氯化钙溶液为基础溶液,添加氯化锂或溴化锂颗粒形成混合溶液来提高单一氯化钙溶液的除湿能力。测量了单一氯化钙溶液,加LiCl/LiBr颗粒后饱和混合溶液的质量浓度,探究极限溶解度,其次对氯化钙、氯化锂不同配比混合溶液在不同温度下的黏度及表面张力进行了测量。通过溶解度的实验测量,发现已经饱和的氯化钙溶液中还可继续溶解最高达8%的LiCl/LiBr晶体。测量得不同配比氯化锂、氯化钙混合溶液的黏度与表面张力值,通过比较发现氯化锂与氯化钙1：1的质量比下,混合溶液的黏度与表面张力均最低。     

Solubility of argon in acetone + water mixed solvent at 288.15, 298.15 and 308.15 K

Solubilities of argon were determined in acetone + water mixed solvent over the full range of composition using a static method. The gas solubilities were measured at three temperatures of 288.15, 298.15 and 308.15 K. The solubility dependence on the temperature in the mixed solvent was measured and discussed, and the similarity between excess quantities of mixed solvent and those of gas solubilities was examined. The order of gas solubility of argon in acetone + water mixed solvent at the three different temperatures was 288. 15 > 298.15 > 308.15 K in the composition range of 0 ≤ x₂2 ≤ 0.15. However, the reverse relationship with temperature was observed in the range of composition of 0.15 < x₂ ≤ 1.0. For all solubility curves, maximum and minimum values of solubility were observed at lower temperatures, but not at higher temperatures. Furthermore, the excess Ostwald coefficients on the basis of volume fraction which express the non-ideality of gas solubility in non-ideal solutions were defined, and they were expressed by a polynomial equation of the Redlich-Kister (1948) type.     

二甲苯与环丁砜混合液粘度和密度测定及关联

在常压下采用U形振动管密度计测定了对二甲苯与环丁砜的混合液在298 15K～353 15K下的密度,用乌氏粘度计测定了此混合溶液在303 15K～353 10K下的粘度,并由密度数据计算出超额体积VE、由粘度数据计算出了不同温度和组成下的混合粘度的变化,同时对不同温度下的超额体积与组成的关系进行了多元回归,对混合粘度变化随组成的关系按Redlich-Kister方程进行了关联。     

氯丁胶浆用低毒性混合溶剂的配制与性能

以混合溶剂替代毒性较大的传统苯类溶剂搅拌溶解氯丁橡胶制备氯丁胶浆,并用胶浆浸渍织物,考察了混合溶剂对氯丁橡胶的溶解性能、胶浆浸润性能的影响,用扫描电子显微镜观察了胶浆对织物的附胶情况。结果表明,采用质量比为4∶5∶1的120#溶剂汽油、乙酸乙酯、碳酸二甲酯配制的混合溶剂,其溶解性能最好,形成质量分数为25%的胶浆速率快,常温下需要45 min,40℃下仅需35 min,该浓度的胶浆黏度为1 067 m Pa·s,约为甲苯溶剂制成的胶浆黏度的一半;胶浆的浸润性能好,前进和后退接触角分别为68.4°和59.6°,均为锐角;浸渍织物表面胶膜厚约13.9μm,比甲苯制成的胶浆胶膜略厚,综合性能略优于甲苯为溶剂制成的胶浆,该混合溶剂是一种可以替代甲苯的氯丁胶浆用低毒性混合溶剂。     

对二甲苯与环己烷、正庚烷、正辛烷、环丁砜和N-甲基-2-吡咯烷酮和乙酸二元混合物在303．15K和323．15K的超额体积和黏度

Experimental data on density and viscosity at 303.15K and 323.15K are presented for the binary mixtures of p-xylene with cyclohexane, n-heptane, n-octane, sulfolane, N-methyl-2-pyrrolidone and acetic acid. From these data, the excess molar volume and deviations in viscosity have been calculated. The computed quantities have been fitted to the Redlich-Kister Equation to derive coefficients and estimate the standard error values. Results are discussed in terms of intermolecular interactions.     

反式-1，2-环己二醇在乙酸甲酯与水混合溶剂中的溶解度

采用激光监视技术测定了1，2-环己二醇在乙酸甲酯和水混合溶剂中的溶解度，并用UNIFAC模型进行了关联，其溶解度预测值与实测值吻合程度良好。     

Enhancement of kinetic rates of CO2 in aqueous solutions of piperazine and methyldiethanolamine with addition of sulfolane

Measurements of kinetics rates of CO₂ in aqueous solutions of methyldiethanolamine (MDEA), piperazine (PZ), and mixtures of (MDEA + PZ), (PZ + sulfolane) and (MDEA + sulfolane) were carried out using the stopped flow technique, and reported in terms of pseudo-first-order rate constants (k₀). When possible, the second-order reaction rate constants (k₂) were regressed from the data. Experiments were performed over new concentration ranges of (10–60), (200–800), (200–800, 10–40), (10–40, 10–200), and (200–800, 10–200) mol/m³ for the above-mentioned five systems, respectively, and at temperatures varying from (298.15–313.15 K). When sulfolane was added to the amine solution, pseudo-first-order rate constants in the mixed solvents were higher than in aqueous MDEA and PZ solutions at all temperatures. The kinetic rates were highest at 298.15 K and decreased at higher temperatures for aqueous (MDEA + sulfolane) solutions but increased with temperature for aqueous (PZ + sulfolane) systems. Reaction orders for both PZ and MDEA were practically one at all sulfolane concentrations and temperatures. The base catalysis mechanism was used to regress very well data for aqueous MDEA and (MDEA + sulfolane + water) and the termolecular mechanism was used for (PZ + sulfolane + water) system. Both the zwitterion and termolecular models were able to fit the experimental data for the aqueous PZ system well. Finally, the termolecular and a hybrid model based on the combination of the Zwitterion and base catalysis mechanisms were able to successfully correlate the experimental data for the mixed aqueous (MDEA + PZ) systems.     

三元低共熔离子液体中CO2的吸收

由N, N-二甲基乙酰胺、氯化胆碱、乙二醇或丙三醇以不同的摩尔比(1:1:3, 1:1:4)合成了一系列三元低共熔离子液体(n_DMA:n_CC:n_{ethylene glycol}=1:1:3, 1:1:4, n_DMA:n_CC:n_glycerol=1:1:3, 1:1:4)。在293.15～323.15 K温度下, 间隔10℃, 0～600.0 kPa压力范围内, 用等温饱和法测量了CO₂在三元体系中的溶解度。CO₂在体系中的溶解度随压力增大呈线性增大趋势, 随温度升高而减小。计算了亨利常数, 结果表明, CO₂在由N, N-二甲基乙酰胺, 氯化胆碱, 乙二醇以摩尔比1:1:3合成的三元体系, 温度为293.15 K下, 亨利常数最小, 最小值为2.174 MPa·kg·mol^-1。报道了关于CO₂吸收的热动力学性质, 包括焓变、熵变、Gibbs自由能变。其中, 焓变为负值, 说明此吸收为放热过程。