Aspen Plus在硫茚萃取精馏工艺中的应用

用Aspen Plus软件模拟硫茚的萃取精馏工艺,通过对精馏塔进料位置、溶剂比和回流比等参数的灵敏度进行分析,确定了相应的优化值;并讨论了灵敏板温控方案.使硫茚萃取精馏在比较经济的条件下进行,并取得了较好的分离效果.     

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。     

萃取精馏萃取剂的一种实验筛选方法

介绍了萃取精馏萃取剂的一种实验筛选方法，汽液平衡仪直接法。并对水一醋酸体系进行了实验，实验结果证明该方法是可行的，可以有效地对萃取精馏的萃取剂进行实验筛选。     

间歇萃取精馏分离乙腈-甲苯共沸体系

应用UNIFAC基团贡献法推导出的萃取剂选择模型,选出异丙苯、对叔丁基甲苯、对二乙基苯为乙腈-甲苯体系的萃取剂,通过气液平衡试验测定了乙腈-甲苯体系和乙腈-甲苯在萃取剂存在下的气液平衡关系,并应用UNIFAC活度系数模型进行气液平衡计算。通过间歇萃取精馏试验考察了不同萃取剂的效果,结果表明,对二乙基苯是最佳的萃取剂,同时研究了回流比、溶剂比对间歇萃取精馏的影响。     

从溶剂油中提纯连三甲苯的萃取精馏溶剂选择

为了快速准确地选择萃取精馏溶剂,由190#溶剂油萃取精馏获取高纯度连三甲苯,运用UNIFAC模型,计算了质量比为4∶1的连三甲苯-茚满体系在苯乙酮、乙二醇、邻苯二甲酸二辛酯、二甲基亚砜和环丁砜5种溶剂中在17.47 kPa下的相对挥发度。同时测定了对应5个体系的汽液平衡数据,计算值和实验值的相对平均偏差均小于6％,两者吻合良好。结果表明：环丁砜较适宜作为萃取剂。与其它萃取剂选择方法比较,这种UNIFAC模型预测和实验验证相结合的方法具有快速准确的优点。     

乙醇-乙酸乙酯体系的间歇萃取精馏研究

在常规的间歇萃取精馏实验装置中,研究了以N,N-二甲基酰胺(DMF)和二甲亚砜(DMSO)作萃取剂;在间歇萃取精馏塔中分离乙醇-乙酸乙酯体系的过程。对全回流时间、不同萃取剂、恒沸物组成、溶剂和混合物的体积比、加盐及加碱等因素考察,分析萃取精馏分离乙醇-乙酸乙酯共沸体系的影响,从而得出最佳的萃取条件。     

低浓度醋酸水溶液的回收

通过三脂肪胺－煤油－正癸醇体系萃取低浓醋酸水溶液的实验，比较了萃取剂三种成分的不同酸比以及温度对分配系数的影响，确定了萃取操作的最佳萃取剂配比及适宜操作温度。通过静态混合器对萃取过程的强化及减压精馏回收萃取剂实验，验证了三脂肪胺－煤油－正癸醇体系萃取低浓醋酸的工业可行性。     

甲醇-丙酮体系的间歇萃取精馏研究

在常规的间歇萃取精馏实验装置中,研究了以蒸馏水为萃取剂间歇萃取精馏分离甲醇-丙酮共沸物的过程。考察了萃取剂、全回流时间、共沸物组成、溶剂与混合物的体积比、加盐、加碱等因素对萃取精馏分离甲醇-丙酮共沸体系的影响,从而得出最佳的萃取条件。     

萃取精馏中萃取剂用量的图解计算方法

萃取精馏中用脱溶剂方法计算萃取剂用量十分繁杂,计算误差大。主要原因是:萃取剂的挥发度小,用数值小的数据关联数值较大的萃取剂用量,可能产生计算误差;在计算过程中脱溶剂的数据与不脱溶剂的数据混用;脱溶剂计算方法没有考虑液气比对分离效果的影响。建立了萃取精馏在三角相图中的几何意义,用浓度杠杆规则可以计算萃取剂的用量。计算结果合理,且符合精馏的各种规律。     

萃取精馏分离甲醇-甲苯共沸物的研究

利用UNIFAC基团贡献法对常用萃取剂进行了筛选,选取邻二甲苯作为该二元共沸物的萃取剂,并通过汽液平衡实验对其分离效果进行了验证;进行甲醇 甲苯分离的间歇萃取精馏实验考察所选萃取剂的效果。结果表明：邻二甲苯能够有效提高甲醇 甲苯的相对挥发度。间歇萃取精馏塔塔板数为30,溶剂比为1,恒回流比(R=3)操作下塔顶得到摩尔分数为99.688%的甲醇产品。     

不同方法及溶剂对黄连小檗碱的提取效果比较

本文采用3种不同方法,分别以乙醇、丙酮、水作为提取溶剂对黄连小檗碱进行提取.以盐酸小檗碱作为对照,用标准曲线法测定各种溶剂及方法提取液中黄连小檗碱的提取率.实验结果表明:采用回流提取法,提取溶剂为乙醇,黄连小檗碱的提取率达到81%以上,标准偏差为0.0005,相对标准偏差为0.06%     

EFFECT OF PARTIAL WETTING ON TRICKLE-BED REACTOR PERFORMANCE

Analysis of trickle-bed reactor data is almost always done by assuming that the catalyst particles are completely covered by a liquid film. The effect on reactor performance from violations of this assumption is demonstrated. The hydrodesulfurization of benzothiophene was simulated with the feed consisting of 10%, by weight, benzothiophene and 90% decalin. The temperature and pressure were held constant at 630 K and 68 atm. The results show that the exit conversion is strongly affected by the wetting efficiency.     

Ozonation/extraction coupled non-catalytic desulphurization of VGO/natural gas condensate

The desulphurization of hydrocarbon fuels with high sulphur content and a wide variety of sulphur-containing compounds brings significant challenges. In the present work, the non-catalytic desulphurization of vacuum gas oil (VGO) and natural gas condensate mixed fuel has been investigated. In this regard, ozone was employed as the oxidant in a bubble column gas–liquid contactor, and an extraction step was further incorporated. The effects of the oxidation reactor scheme, ozonation time, and extraction with different solvents, applying pre- and post-extraction strategies (i.e., ozonation/extraction/extraction and extraction/ozonation/extraction), have been studied. It was found that pre-extraction of mixed fuel increases the oxidative desulphurization (ODS) efficiency due to the removal of light sulphur-containing compounds (SCCs). N-methyl-2-pyrrolidone (NMP) has been found to be the most effective extraction agent, removing 44% of sulphur by pure extraction and 77.4% by ozonation + extraction. However, in terms of fuel loss, dimethylformamide (DMF) performs better than NMP, and it has been shown to be the most appropriate solvent for achieving a 90% desulphurization ratio. Finally, it was found that the applied procedure could effectively remove the wide range of SCCs, especially refractive components such as benzothiophene (BT) and dibenzothiophene (DBT).     

EFFECT OF PARTIAL WETTING ON TRICKLE-BED REACTOR PERFORMANCE

Analysis of trickle-bed reactor data is almost always done by assuming that the catalyst particles are completely covered by a liquid film. The effect on reactor performance from violations of this assumption is demonstrated. The hydrodesulfurization of benzothiophene was simulated with the feed consisting of 10%, by weight, benzothiophene and 90% decalin. The temperature and pressure were held constant at 630?K and 68?atm. The results show that the exit conversion is strongly affected by the wetting efficiency.     

基于离子液体的燃料油萃取脱硫过程

以咪唑类离子液体作为萃取脱硫剂,在正戊烷和甲苯的混合溶液中加入少量的噻吩构成油品模拟体系. 采用正交实验,系统考察了单级萃取中温度、时间、剂油比以及离子液体碳数对脱硫效率的影响,得到了较优的脱硫条件：温度约40℃,反应时间约50 min,剂油比为1:1,侧链碳数为10. 回归得到了模拟油品中脱除噻吩的萃取动力学方程. 该研究为基于离子液体的燃料油脱硫工艺提供了重要的基础.     

超声波和微波辐射下萃取煤的有机硫形态分析

用超声波和微波辐射法在四氯乙烯体系下,采用气相色谱／质谱仪对北京煤、王庄煤、兖州煤和临汾煤进行了萃取液分析．结果表明,不同煤样在超声波作用下的脱硫效果不同,不同煤样四氯乙烯萃取物中分别含有苯并噻唑、苯并噻吩、噻克索酮、2-甲基-4-叔丁基苯硫酚、噻唑基嘧啶、甲苯噻嗪、5-乙氨基-噻唑基嘧啶、4-氨基-噻嗪、4-甲氧基-2-甲基-1-甲硫醚基苯、2-甲硫基-苯并噻唑和2-甲硫基-苯甲酸甲酯等硫化物。     

苯酚羟化液多级萃取分离及磷酸三丁酯配合萃取过程

针对甲基异丁基甲酮(MIBK)和异丙醚(DIPE)两种萃取剂以及在不同剂溶比时萃取苯酚羟化液的萃取效果进行了比较;并进一步采用磷酸三丁酯(TBP)为配合剂、甲基异丁基甲酮(MIBK)为稀释剂研究了苯酚羟化液的配合萃取.结果表明:MIBK的萃取效果优于DIPE,MIBK为萃取剂时的最优剂溶比为1:3,此时苯酚羟化液的三级错流萃取率可达99%发上.通过MIBK对羟化液的多级错流萃取过程模拟计算进一步验证了此结论.采用TBP络合萃取苯酚羟化液,实验表明,萃取率可达到99.76%.     

错流萃取分离二乙氧基甲烷与乙醇的模拟及实验研究

设计了二乙氧基甲烷和乙醇水溶液的错流萃取分离工艺,实验确定了以多元醇和水为复合萃取溶剂分离二乙氧基甲烷-乙醇体系适宜的比例.采用相分配系数法对该过程进行了模拟计算及萃取实验.实验及模拟结果表明:当原料与2种溶剂进料体积比为1:1:1时,经过3级错流萃取分离后,萃余相中二乙氧基甲烷质量分数可达99.9%,收率达99.0%...     

多级逆流液液萃取法浓缩糠醛的研究

分别选择1,1,1-三氯乙烷和四氯化碳为萃取溶剂,研究液液萃取法浓缩糠醛过程,以UNIQUAC方程为平衡模型,建立逆流模拟计算框图,计算结果表明1,1,1-三氯乙烷和四氯化碳是糠醛浓缩的有效溶剂,在N=4时,分离后糠醛质量分数达99.3%以上,萃余液中糠醛质量分数可降至0.07%以下,以1,1,1-三氯乙烷为萃取剂,分离后糠醛质量分数达99.9%以上,收率达到98.5%以上;在模拟计算的基础上,建立液液萃取装置并进行试验,试验和模拟结果基本一致,研究结果为进一步放大试验研究提供了有效的依据。     

Effect of various solvents on the extraction of protein fractions of beans (Phaseolus vulgaris)

A study was carried out to determine the effect of different solvents on the extraction of protein fractions in beans. Black bean protein was extracted with the following solvents: distilled water, 0.01 M sodium hydroxide, 0.05 M sodium chloride, and 70% ethanol. By using each solvent under different conditions, it was possible to establish the optimum ones for the best extraction and fractionation of proteins from leguminous seeds. These conditions were the following: one hour agitation at room temperature, three successive extractions with the same solvent, and a ratio of solid to solvent of 1:20 W/V. The effect of 24 different sequences of solvents upon the extraction of protein was also investigated. From the extraction point of view, the best sequence of solvents for extracting the protein was that where NaOH constituted the first solvent used; this sequence, however, has the disadvantage of extracting all the protein from the seed, making it impossible to separate other protein fractions by another solvent. If the purpose of the extraction is to separate different protein fractions, the best sequence of solvents is distilled water or sodium chloride in the first place, followed by ethanol and sodium hydroxide. The need for using standardized methodology for the fractionation of protein from seeds in order to obtain comparable data between research laboratories is emphasized.