复合型缓蚀剂对碳酸丙烯酯脱碳工艺过程稳定性的研究

按一定比例加入复合型缓蚀剂（７０１９＋ＨＥＤＰ）于工业碳酸丙烯酯溶液中，以合成氨生产过程的变换气进行了吸收二氧化碳的中间试验，碳酸丙烯酯溶剂的降解试验及运转时起泡性能进行测试和解决方法，并与未加复合缓蚀剂的碳酸丙烯酯溶剂进行对比运行试验研究。结果表明７０１９与ＨＥＤＰ的复合缓蚀剂的加入，对碳酸丙烯酯脱碳工艺过程的稳定性基本上无不良影响。     

溴化锂制冷技术在2.7MPa碳酸丙烯酯脱碳中的应用

介绍热水型溴化锂制冷机组的工作原理、特点,概述了该技术在2.7 MPa碳酸丙烯酯脱碳工段中的应用情况.实际运行情况表明:碳酸丙烯酯溶液温度降低了约15℃,脱碳净化气中二氧化碳体积分数由0.8％～1.0％降至0.5％,吨氨碳酸丙烯酯溶液损耗减少约0.2 kg,节能降耗效果显著.     

碳酸丙烯酯脱碳过程的水平衡及控制技术

在碳酸丙烯酯脱碳过程中,溶剂含水后对工艺和设备均有不利影响。本文根据碳酸丙烯酯—水系统气液平衡理论,分析了影响碳酸丙烯酯脱碳过程中工业循环溶剂中含水量的因素,提出了控制碳酸丙烯酯脱碳过程中水平衡的途径和方法。     

高精度过滤机在化肥行业中的应用

桂林澄宇通用设备有限公司继1997年开发生产的LH系列化工过滤机在化肥厂精炼工序，用于过滤醋酸铜氨液获得成功后，接着又开发了用于过滤碳酸丙烯酯溶液、NHD溶液及热钾碱溶液的脱碳液过滤机并获得成功。     

脱碳闪蒸气的回收技术

0前言 山东明水化工有限公司“18·30”工程中脱碳工段采用技术成熟的2．7MPa碳酸丙烯酯脱碳工艺,采用2台Ф3000mm脱碳塔并联设计。其工艺流程：碳酸丙烯酯溶液在脱碳塔内吸收了CO2气体后,经4级降压3级闪蒸,把大部分CO2气体脱除;得到解析后的碳酸丙烯酯溶液（碳丙液）再由脱碳泵打入脱碳塔内循环使用;常解气和真解气去尿素系统,闪蒸气放空处理。整个脱碳装置具备配套300kt／a合成氨的生产能力。     

碱性离子交换树脂催化碳酸丙烯酯水解反应研究

本文研究了碱性离子交换树脂催化碳酸丙烯酯水解反应制备1,2-丙二醇.详细考察了催化剂种类及其用量、酯水比、反应温度与反应时间对碳酸丙烯酯水解反应的影响.在最佳反应条件下碳酸丙烯酯的转化率和1,2-丙二醇的选择性均大于99%;同时考察了最佳反应条件下催化剂的重复使用性.     

高精度过滤机在化肥行业中的应用

我公司开发生产的LH系列化工过滤机的过滤精度在超滤(≤0．1μm)与微滤(≥0．5μm)之间，于1997年在化肥厂精炼工段醋酸铜氨液的过滤中应用成功之后，又先后在碳酸丙烯酯溶液、NHD溶液及热钾碱溶液的过滤中应用成功。     

国内小合成氨节能技术

推广低温变换工艺技术，淘汰中变或中串低技术，该技术分全低变和中低变两种，可根据企业的不同情况选用，该技术实施后，变换系统蒸汽消耗可降至300kg以下；采用聚乙二醇二甲醚(NHD)或改良的碳酸丙烯酯脱碳技术；铁一碱溶液催化法气体脱硫技术     

负载锡的水滑石类化合物催化合成碳酸丙烯酯

通过浸渍法制备了负载Sn的镁铝水滑石类化合物Sn/HT.利用X-射线衍射(XRD)技术对催化剂的结构进行了表征.研究了其对尿素与1,2-丙二醇合成碳酸丙烯酯的催化性能.考察了催化剂制备条件、反应条件和催化剂的再生性能.结果表明,负载Sn的镁铝水滑石的焙烧产物对尿素与1,2-丙二醇合成碳酸丙烯酯具有比较好的催化活性.当水...     

碳酸丙烯酯脱CO_2试验情况介绍

<正> 碳酸丙烯酯是一种高效吸收溶剂,用来脱除天然气、石油裂解气、油田气及合成氨变换气中的CO_2和H_2O。目前在我国氮肥工业中是一项正在发展的净化技术。1958年美国Fluor公司首先利用碳酸丙烯酯来净化脱除CO_2。CO_2在碳酸丙烯酯中的溶解度是水的四倍,并且有性质稳定、无毒、无腐蚀、挥发性小、省电、省热能、流程和操作简单等优点。它同加压水洗法类似,是一种物理吸收方法。国内由南京化工研究院在1976年完成了在28kg/cm~2和18kg/cm~2两种条件下进行碳酸丙烯酯脱碳的模拟试验,取得与国外类似的结果。并与化工部六院合作做了气液平衡数据及传质动力学的研究,完成了用碳酸丙烯酯脱除日产150     

碳酸乙烯酯和碳酸丙烯酯复合溶剂的工业脱碳性能研究

在碳酸乙烯酯（乙碳）和碳酸丙烯酯（丙碳）复合溶剂脱除合成气ＣＯ２中试实验的基础上,就乙碳和丙碳的分子结构特点对乙碳和丙碳及两者复合溶剂的ＣＯ２吸收性能进行了比较,讨论了乙碳－两碳－水复合溶剂的相行为及其对工业操作的影响,并验证了乙碳－丙碳复合溶剂应用于工业的可行性及其特点。     

Preparation of chlorinated poly(propylene carbonate) and its effects on the mechanical properties of poly(propylene carbonate)/starch blends as a compatibilizer

Polymer Bulletin - Poly(propylene carbonate) (PPC) was chemically modified by chlorine through water phase suspension chlorination reaction, and the product was named as chlorinated poly(propylene...     

Efficient propylene carbonate synthesis from propylene glycol and carbon dioxide via organic bases

Organic bases were first used as effective catalysts for the synthesis of propylene carbonate from propylene glycol and carbon dioxide in the presence of acetonitrile. Acetonitrile in the reaction acted as not only the solvent but also the dehydrating reagent to remove the water produced from the reaction. It was interesting that upon ammonium carbonate being introduced into the reaction system, the catalytic selectivity was significantly enhanced. With 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as the catalyst, the yield of propylene carbonate could reach 15.3% with the selectivity of 100% under the optimal conditions.     

改性聚碳酸亚丙酯的研究现状

二氧化碳与环氧丙烷共聚得到可生物降解的聚碳酸亚丙酯,聚碳酸亚丙酯是一种新型热塑性脂肪族聚碳酸酯,具有良好的生物相容性和降解性。但是聚碳酸亚丙酯的热力学稳定性和力学性能不好,必须对其改性。综述了聚碳酸亚丙酯的常用改性方法并对改性聚碳酸亚丙酯的发展做了展望。     

合成碳酸丙烯酯产物的气相色谱分析

采用气相色谱法测定合成碳酸丙烯酯产物中碳酸丙烯酯、水和１，２ 丙二醇等杂质含量。在检测器ＴＣＤ、１８０℃、填充有聚二乙二醇丁二酸酯涂渍的硅烷化１０２白色担体的不锈钢填充柱上，样品中的组分获得分离。采用校正归一化法进行定量分析，相对标准偏差ｓ小于６９％     

CO2在碳酸二甲酯溶剂中溶解度的测定

采用恒定容积法测定了不同温度下CO2在碳酸二甲酯溶剂中的溶解度。结果表明,溶解度随压力升高而增大,随温度升高而减小。实验结果与基于正规溶液理论的PS法估算值比较符合。在相同条件下,CO2在碳酸二甲酯中的溶解度比在碳酸丙烯酯中的溶解度平均约高30%。     

An investigation of the electrochemical reduction of pentachlorophenol with analysis by HPLC

A study has been made of the electrochemical reduction of pentachlorophenol (PCP) on a lead electrode in both water and propylene carbonate. A combination of voltammetric measurements and analysis of reaction products by high performance liquid chromatography (HPLC) have established that the reduction of PCP in propylene carbonate occurs by two different pathways, depending upon the electrode potential. At -1.9V vs SCE, reduction is mediated by adsorbed hydrogen, whereas at -2.3V vs SCE direct reduction of PCP also occurs. A similar approach has established that the reduction of PCP in water follows only one reaction pathway, namely, direct electron transfer from lead to PCP.     

Copolymerization of carbon dioxide and propylene oxide with zinc glutarate as catalyst in the presence of compounds containing active hydrogen

To enhance the catalytic copolymerization of CO₂ and propylene oxide catalyzed by zinc glutarate, the influence of trace of water, ethanol, and propanal on the catalytic activity, the resulted copolymer structure, and the molecular weight and molecular weight distribution of the copolymer were investigated extensively. The experimental results showed that the catalytic activity decreased remarkably in the presence of either trace of ethanol or water, but increased in the presence of trace of propanal. Both ¹H‐NMR and ¹³C‐NMR spectra suggested that the content of carbonate linkages of resulted copolymer was not effected obviously in the presence of above‐mentioned impurities, giving completely alternating poly(propylene carbonate) (PPC). GPC results indicated that these impurities reduced the molecular weights but broadened the molecular weight distributions of resulted copolymers. Finally, the byproduct contents including both propylene carbonate determined by GC and polyether increased with the increase of three impurity concentrations. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Experimental and Kinetic Studies on a Homogeneous System for Diethyl Carbonate Synthesis by Transesterification

A synthesis of diethyl carbonate through transesterification of propylene carbonate and ethanol, coproducing useful propylene glycol, was carried out in the presence of sodium ethoxide as catalyst. The effects of reaction parameters such as catalyst concentration, mole ratio of ethanol to propylene carbonate and reaction temperature on the transesterfication reaction were investigated. The results showed that the reaction is reversible with a propylene carbonate equilibrium conversion of about 64 % at an ethanol to propylene carbonate mole ratio of 8.0 and a reaction temperature of 303 K. A kinetic model was proposed based on the reaction mechanism. The model parameters were estimated by the Runge‐Kutta method. The statistical test showed that the model calculation results were in good agreement with the experimental data.     

Kinetic study of CO2 fixation into propylene carbonate with water as efficient medium using microreaction system

Carbon dioxide (CO₂) utilization and fixation have become one of the most important research areas nowadays due to the increase of global greenhouse effect. Cyclic carbonate, which is widely used in various fields, can be synthesized by fixation of CO₂ with epoxide in industry. Moreover, the synthesis of cyclic carbonate is a 100% atom economical reaction, which makes it eco-friendly and promising. To enhance the reaction efficiency and safety, a microreaction system was used as the platform for cycloaddition reaction. In this work, tetrabutylammonium bromide (TBAB) was chosen as catalyst, and propylene oxide (PO) as a mode substrate. Interestingly, the addition of water can increase the propylene carbonate (PC) yield and decrease the activation energy considerably, proving water as catalyst promoter for PC synthesis. PC yield and selectivity could reach 91.6% and 99.8%, respectively. The Influence factors and kinetic equation for CO₂ cycloaddition were obtained as well.