反应精馏合成乙酸乙酯

提供了用浓硫酸作催化剂、在填料塔中得到较高纯度乙酸乙酯的方法。考察了进料比、回流比、进料温度、釜温等对塔顶酯含量的影响，找出了较佳的工艺条件和主要控制参数     

反应精馏法提纯乙酸乙酯的研究

研究了通过化学反应精馏和加盐脱水联合分离乙酸乙酯-乙醇-水混合物的过程,探讨了该条件下反应精馏的流程、操作条件和加盐脱水的效果.流程中包括了控制可逆反应单向进行的反应条件,共沸蒸馏的操作参数,以及液-液分相去除水分的效果.文中最后给出了实验数据对理论分析的验证.     

反应精馏——萃取联合过程合成乙酸乙酯的研究

将固体酸作为主催化剂与不锈钢填料以一定的规律置于反应精馏塔中，以一路易斯酸作为辅助催化剂置于塔釜中，采用反应精馏的形式连续合成乙酸乙酯。塔顶全部酯相经萃取脱去水后再引起部分回流到反应精馏塔塔顶，构成了反应精馏－萃取联合过程。该过程酯化转化率主，酯相带水能力强，减少了回流比，降低了能耗，提高了设备的生产能力。     

反应精馏合成乙酸乙酯

提供了用浓硫酸作催化剂、在填料塔中较纯度乙酸乙酯的方法，考察了进料比、回流比、进料温度、釜温等对塔顶酯含量的影响，找出了较佳的工艺条件和主要控制参数。     

反应精馏制备乙酸乙酯的工艺分析

为揭示反应精馏法制备乙酸乙酯的特性及得到较高纯度的产品,并为反应精馏工艺过程的深入研究及工业化提供理论依据,应用Aspen Plus软件模拟分析反应精馏过程。结果表明：给定回流比的情况下,理论塔板数、精馏段塔板数及进料位置、进料比、催化剂用量等参数均对产品纯度及分离效果产生影响。     

应用ChemCAD软件模拟反应精馏过程

应用ChemCAD软件中的SCDS精馏模型，对乙酸和乙醇反应生成乙酸乙酯的反应精馏过程进行了模拟，对过程参数对反应的影响进行了计算，选择了合适的反应条件。     

反应精馏—萃取联合过程合成乙酸乙酯的研究

将固体酸作为主催化剂与不锈钢填料以一定的规律置于反应精馏塔中，以一路易斯酸作为辅助催化剂置于塔釜中，采用反应精馏的形式连续合成乙酸乙酯。塔顶全部酯相经萃取脱去水后再引出部分回流到反应精馏塔塔顶，构成了反应精馏－萃取联合过程。该过程酯化转化率高，酯相带水能力强，减少了回流比，降低了能耗，提高了设各的生产能力。     

带侧线反应精馏-渗透汽化生产乙酸乙酯集成过程模拟与分析

针对乙酸酯化法生产乙酸乙酯分离过程复杂、能耗大的缺点,提出了一种带侧线反应精馏-渗透汽化（RD-PV）集成过程。通过反应精馏塔侧线采出和渗透汽化膜组件及时移出水分,促进酯化反应向正反应方向进行,在达到乙酸高转化率的同时使乙酸乙酯产品达到高纯度。研究了反应精馏塔侧线采出位置、采出比、反应段塔板数、精馏段塔板数以及膜组件个数等对年度总成本（TAC）的影响,获得了TAC达到最小的过程参数。与传统双塔精馏分离过程对比,RD-PV集成过程节省能耗26.6%,但膜材料价格对RD-PV集成过程的TAC有较大影响,随着渗透汽化技术的成熟,当膜材料价格低于1913 CNY·m^-2时,RD-PV集成过程在经济上占据优势。     

反应精馏法合成乙酸乙酯工艺条件的选择

乙酸乙酯是一种重要的有机化工产品,有着非常广泛的用途,生产方法多种多样。采用反应精馏技术,以乙酸和乙醇为原料,浓硫酸为催化剂,采用间歇式进料,对酯化反应生成乙酸乙酯的工艺条件进行了研究。应用气相色谱对产物组成进行了分析。通过实验,确定了该反应的最佳反应条件：醇酸体积比为1．2：1,回流比为4：1,反应时间为2．5h,催化剂用量0．8g。在此条件下,乙酸的转化率达到了93．25％,乙酸乙酯的选择性为79．09％,乙酸乙酯的收率达到了73．76％,均高于传统方法。     

反应精馏合成醋酸正丁酯的模拟和优化

利用Aspen Plus模拟了合成醋酸正丁酯的反应精馏过程,并分析各工艺参数对产品纯度和再沸器热负荷影响。通过优化得出最佳工艺参数为:理论塔板数为16;精馏段、反应段和提馏段塔板数分别为5、7和4;醋酸和正丁醇的进料塔板数分别为5和7;酸醇进料比为1:1;回流比为1。在此条件下产品醋酸正丁酯的纯度达99.55%;乙酸的转化率达99.71%,再沸器的能耗较低。     

连续反应精馏合成乙酸异丙酯

以乙酸和异丙醇为原料通过连续反应精馏合成乙酸异丙酯，实验研究了影响反应的因素，结果表明最佳合成条件为：酸醇比1：1．2，回流比3，异丙醇的进料流量2mL／min，硫酸用量为乙酸体积的2％，乙酸异丙酯的最大收率为92．5％。     

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。     

离子液体应用于连续催化酯化制备乙酸乙酯

首先在间歇反应条件下考察了基于吡咯烷酮/咪唑阳离子的5种硫酸氢盐离子液体作为催化剂用于乙酸和乙醇酯化反应的催化活性,并与浓硫酸进行了比较。然后选取成本最低和催化效果较佳的离子液体——2-吡咯烷酮硫酸氢盐离子液体([Hnhp]HSO4),采用反应精馏技术,进行了连续酯化制备乙酸乙酯的研究。结果表明,当釜液酸醇比为6∶1(均为摩尔比),[Hnhp]HSO4用量为乙酸物质的量的0.5%,釜温110℃,原料进料速度为40 m L/h,进料醇酸比为1.02∶1,回流比为1,回流酯流速为35 m L/h,反应48 h,塔顶粗酯的酯含量达94%~96%,过程可保持较好的连续性和稳定性。相比于传统的浓硫酸催化剂,离子液体[Hnhp]HSO4对设备腐蚀性小,对环境友好。     

DWC塔反应精馏法合成乙酸乙酯的工艺研究

实验研究隔离壁塔反应精馏法催化合成乙酸乙酯系列工艺条件,发现该方法有生产工艺简单,条件温和,时间短,产品中副产物少,转化率高,产品质量较好,可以在反应的同时,对产物进行初步分离以便充分有效利用能源,具有较好的经济效益等优点。隔离壁塔反应精馏法合成乙酸乙酯最佳工艺条件：催化剂用量占总投料量的3‰,反应时间2 h,釜温控制180℃,柱温控制110℃,反应床层高度120 cm,乙酸和乙醇投料比1∶1.3（mol比）,回流比1∶3时,乙酸转化率达到98.90%。     

Coproduction of Ethyl Acetate and n‐Butyl Acetate by Using a Reactive Dividing‐Wall Column

The performance of the reactive distillation dividing‐wall column for coproduction of ethyl acetate and butyl acetate was experimentally studied. n‐Butanol and ethanol are raw reaction materials that react with acetic acid in the reaction zone to produce n‐butyl acetate and ethyl acetate, respectively. n‐Butyl acetate is not only a product, but also acts to remove water generated by the esterification reactions. The effects of various parameters, such as catalyst loading per stage, reflux ratio, liquid split and molar feed ratios, ethyl acetate/n‐butyl acetate purity, pressure drop, and total energy consumption, are investigated. Results show that ethanol could be completely converted and the products could be easily separated, which shows great industrial application potential in the coproduction of ethyl acetate and n‐butyl acetate.     

Analysis of the Start‐up Process for Reactive Distillation

The start‐up procedure of a distillation column is a time‐ and energy‐consuming process. Further, the products during the start‐up time are off specification and cannot easily be recycled as for conventional distillation but must costly be disposed of. In this paper, a process model to simulate the barely analyzed start‐up procedure for a reactive distillation from the cold and empty state to steady state is presented. The start‐up of a reactive distillation column has been modeled with gPROMS. The advantage of a cold and empty start‐up is the consistent and reproducible initialization. Commercial simulators do not give the opportunity to start form a cold and empty state, e.g., a column modeled with Hysys must be shut down from a steady state to be able to model the complete start‐up process, which is not possible, for example, for a batch process. Also, a change in the describing equations and discontinuities in process variables is difficult to handle within the simulation. In this paper, the start‐up strategies normally used for distillation without reaction are examined and applied to reactive distillation. It will be shown that the widely used strategy of total reflux is not suitable for reactive distillation. A simplified model to derive a time constant which describes the influence of parameter setting changes, like heating power, reflux ratio and feed composition on the start‐up time, is introduced and validated.     

Optimization of Reactive Dividing‐Wall Distillation Column for Ethyl t‐Butyl Ether Synthesis

Ethyl t‐butyl ether (ETBE) was synthesized via reaction of ethanol and isobutene by means of a reactive dividing‐wall distillation column (RDWC). The RDWC was simulated using the RADFRAC model of Aspen Plus. Multi‐response optimization by response surface methodology (RSM) with desirability function approach was applied for maximizing product purities and minimizing energy requirements and CO₂ emissions simultaneously with a constraint that the difference in pressure drop across the dividing wall should be zero. The prediction from the RSM optimization agrees well with the simulation. The optimized RDWC provided an excellent purity of 99.99 mol % of the product ETBE with about one‐third reduction in energy requirements and CO₂ emissions as compared to reactive distillation.