非等温模拟移动床反应器合成乙酸甲酯过程中产品收率和溶剂消耗的多目标优化

模拟移动床反应器(SMBR)通过引入反应物和产物的连续逆流色谱分离,可以明显提高可逆化学反应的转化率。本文以Amberlyst15催化合成乙酸甲酯作为模型体系,在恒定的设备产率和适合的纯度约束条件下,同时对产品收率和溶剂消耗进行多目标优化。基于多目标优化所得非劣解,评价和比较了5种温度变化对4柱SMBR反应性能的影响。     

三甲基乙酸及三甲基乙酸甲酯的合成

对叔丁醇与甲酸反应合成三甲基乙酸的方法进行了改进。反应时间2.5h,所用甲酸的含量在99%以上,产率69%。位阻大的三甲基乙酸与甲醇反应的配料比为1:5。回流时间6～8 h。酯化产率高达80%。     

反应精馏隔壁塔内合成乙酸甲酯的模拟

提出了一种应用反应精馏隔壁塔合成乙酸甲酯的新工艺流程,采用反应精馏隔壁塔替代常规反应精馏流程中的反应精馏塔及甲醇回收塔。利用Aspen Plus模拟软件,对反应精馏隔壁塔及常规流程进行了模拟,比较分析了两种流程塔内液相组成分布,并分析了塔顶回流比与气相分配比对反应精馏隔壁塔的影响。结果显示新流程可以节能11.9%,并能降低设备投资费用和操作费用。     

甲氧基乙酸甲酯的合成及应用进展

甲氧基乙酸甲酯不仅是一种合成维生素B_6、周效磺胺等药物的重要原材料,而且还是更经济合理合成乙二醇的重要原材料。当前制备工艺主要包括甲醛和甲酸甲酯偶联法、氯乙酸类和甲醇钠取代法、乙二醇单甲醚氧化法和甲缩醛羰基法。分析了制备甲氧基乙酸甲酯的方法的优缺点,综述了甲氧基乙酸甲酯在应用领域的研究进展,并对其发展趋势和应用前景作了展望。     

乙酸甲酯的合成与应用新进展

介绍了近几年国内外有关乙酸甲酯合成与应用的研究新进展，提出了甲醇脱氢合成法，并重点探讨和比较了反应精馏法和甲醇羰化法的合成研究，对发展乙酸甲酯工业具有指导意义。     

活性炭负载对甲苯磺酸催化合成乙酸甲酯

以乙酸和甲醇为原料,以活性炭负载对甲苯磺酸为催化剂,催化合成乙酸甲酯。考察了醇酸摩尔比、活性炭负载对甲苯磺酸催化剂用量、反应时间和反应温度等因素对合成乙酸甲酯产率的影响。结果表明,在甲醇、乙酸摩尔比为1.3∶1、活性炭负载对甲苯磺酸用量为反应物总质量的1.5%,反应时间为150mim,反应温度为90℃的条件下,其产率达98.6%;催化剂寿命长、可多次重复使用。     

乙酸甲酯合成路线及催化剂研究进展

综述了目前工业生产乙酸甲酯的主要途径,阐述了各条生产路线的利弊;重点介绍了无卤非贵金属的分子筛催化剂上二甲醚羰基化制备乙酸甲酯反应,阐述了详细的反应历程、反应机理及催化剂的最新研究进展。     

基于双种群算法的模拟移动床多目标操作优化

以有限元法求解模拟移动床的稳态TMB模型和动态SMB模型,提出基于Pareto非劣解集的多目标双种群遗传粒子群算法;利用动态SMB模型仿真模拟移动床色谱吸附分离过程,以分离纯度和性能指标分别作为约束条件和目标函数进行多目标操作优化设计.仿真结果表明,SMB模型较之TMB模型更真实可靠,双种群遗传粒子群算法也较单一种群的...     

强酸型阳离子树脂催化合成乙酸甲酯

文章以D072强酸性阳离子树脂为催化剂,乙酸和甲醇为原料,在常压下合成乙酸甲酯。该文研究了树脂种类、树脂用量、酸醇比、反应温度和反应时间等因素对酯化反应过程的影响。在不分离产物的情况下,合成乙酸甲酯的反应条件为:醇与酸摩尔比为1.3∶1,反应时间2.5h,催化剂用量5g,反应温度为60℃,酯化率达到72.32%,催化剂可重复使用。     

微粒群算法在模拟移动床色谱分离过程优化中的应用

运用微粒群算法开发出一种非线性模拟移动床(SMB)色谱分离过程的优化策略.该优化策略将模拟移动床的最大吸附剂生产率作为优化问题的目标函数,采用模拟移动床的TMB模型来计算微粒群优化算法的适应值.采用该优化算法对手性化合物萘酚对映体(bi-naphthol)的模拟移动床色谱分离操作条件进行了优化,仿真结果表明了该优化策略的有效性.     

模拟移动床的控制系统设计和优化

为了满足现代化工业色谱分离的要求,对模拟移动床(SMB)色谱分离的工艺流程进行了改进,设计了一套由工控机、PLC和智能仪表构成的模拟移动床集散控制系统。用改进的BP神经网络对苯丙氨酸模拟移动床的色谱分离过程进行了建模,用实数编码的遗传算法对分离参数和操作条件进行了优化,并在实际中得到应用,使得产品的纯度和回收率都得到了较大的提高。并且在开发过程中,上位机软件采用国产“组态王”和VB相结合的方式,克服了“组态王”命令语言环境较弱的缺点。     

Coal Gasification in Moving Bed Reactor with a Draft Tube

1 INTRODUCTIONMany different types of reactors,for example,fixed bed,moving bed,fluidized bed and spoutedbed,have been used in industrial production and laboratory in research studies.Althougheach of these coal gasifiers has its own specific advantages,there exists,generally speaking,certainwaste gas in product gas because of the direct burning of coal with oxygen or air to provide heatneeded in the endothermic process of coal gasification in gasifiers.A new type of moving bed     

Optimal Operation of Simulated Moving Bed Technology on Utilization of Naphtha Resource

Simulated moving bed (SMB) technology has attracted more and more attention in recent decades. The simulated moving bed (SMB) technology on optimal utilization of naphtha resource was studied in this paper. A simulated moving bed equipped with 16 columns was used to separate normal paraffins from naphtha. The effects of temperature (T), switching time (t_s), extract oil flow rate (L_AD), feed flow rate (L_F), and desorbent flow rate (L_D) on the separation performance were investigated, and the desorbent recycle process was simulated by Aspen Plus. The results showed that the optimal conditions for simulated moving bed were operation temperature (T) of 170°C, switching time (t_s) of 900 s, extract oil flow rate (L_AD) of 10 mL/min, feed flow rate (L_F) of 5 mL/min, and desorbent flow rate (L_D) of 20 mL/min. Through the SMB and the desorbent recycle system, the purity of the de-solvent extract oil (DEO) reached 98% and the purity of the de-solvent raffinate oil (DRO) reached 92%, which were the high-quality feed for the ethylene cracking process and the catalytic reforming process, respectively.     

模拟移动床分离盐酸度洛西汀的研究

通过HPLC单柱实验,确定了盐酸度洛西汀的拆分条件。采用平衡扩散模型对盐酸度洛西汀在8柱四区模拟移动床上的线性分离过程进行了模拟,主要考察了切换时间对分离效果的影响。在适宜的操作条件下,达到了较好的分离效果。两种对映体的纯度分别达到99.67%和99.62%,回收率分别达到了96.30%和97.14%。本研究对盐酸度洛西汀的生产应用具有一定的指导意义和参考价值。     

Analysis of the Behavior of the Simulated Moving Bed Reactor in the Sucrose Inversion Process

Abstract

The simulated moving bed reactor (SMBR) is a device in which reaction and separation processes take place simultaneously. The separation of products allows higher conversion and high‐purity product can be also obtained. In this work, a mathematical model has been presented to predict the behavior of the SMBR in the sucrose inversion process. For this process, the triangular region which defines operating conditions to recover high‐purity products in SMBR has been obtained using two modeling strategies. The set of partial differencing equations is solved by finite volume method. The influence of some operation conditions on the reactor performance is analysed for the sucrose inversion process.     

Modeling Study on a Three-Zone Simulated Moving Bed without Zone I

A three-zone SMB was proposed to reduce the adsorbent usage, where zone I normally used to regenerate the adsorbent is discarded and the desorbent is directly pumped into zone II. An analysis on the movement of the concentration band indicates that the tail of the more retained solute is desorbed successively in zones II and IV, without overlapping with the front of the less retained solute in zone IV. As a result, the raffinate and extract product can be collected from the outlets of zones III and IV, respectively. The model simulations confirm that the three-zone SMB dropping zone I can lower the adsorbent usage and system pressure without losing the purity. In comparison with the four-zone SMB and another three-zone SMB dropping zone IV, the solvent consumption is lower than that by the latter, but higher than that by the former. The partial withdrawal operation can reduce the solvent consumption in the two SMBs without zone I and without zone IV. For anti-Langmuir isotherm dropping zone I is more effective than dropping zone IV.     

模拟移动床色谱分离替考拉宁条件研究

探讨了用模拟移动床色谱分离提纯替考拉宁的可行性 ,且优化出最佳分离条件为 ts=1 0min,υF=0 .0 8m L/min,υp=1 .5 m L/min,υD=0 .8m L/min,CF=8mg/m L。     

溶剂梯度模拟移动床分离奥美拉唑对映体的研究

模拟移动床一般在平衡模式下操作,即在模拟移动床（SMB）各区中采用相同的温度、压力和流动相组成等操作条件。但最新研究表明,在SMB各区适当使用梯度操作,如温度梯度、压力梯度、溶剂梯度等,优化各区操作条件,可以显著改善分离性能。本文测定了奥美拉唑对映体在乙醇／正己烷中的吸附平衡,根据SG—SMB平衡理论,确定了分离奥美拉唑对映体的完全分离区域,并以此为指导初步选择了分离条件,使R—OME和S—OME纯度分别达到95．11％和96．34％。