氯苯连续绝热硝化合成硝基氯苯过程设计

依据氯苯绝热硝化反应合成硝基氯苯工艺过程的特点和中试试验结果,对5万t/a硝基氯苯生产过程中,氯苯连续绝热硝化反应合成硝基氯苯过程进行了设计。该过程主要由SV-5/100型18 m长静态混合硝化反应器、耐腐高压泵、涡轮流量计、氯苯槽、混酸槽等组成。该工艺过程具有反应速率高、过程安全可靠、物料及能量的利用效率高、三废量少、操作费用低、产品质量稳定等优点。     

Vapor–liquid equilibria of hydrogen chloride,phosgene, benzene,chlorobenzene, ortho‐dichlorobenzene,and toluene by molecular simulation

Vapor–liquid equilibria (VLE) of nine binary mixtures containing hydrogen chloride or phosgene in the solvents benzene, chlorobenzene, ortho‐dichlorobenzene, and toluene as well as the mixture hydrogen chloride + phosgene are predicted by molecular modeling and simulation. The underlying force fields for the pure substances are developed on the basis of quantum chemical information on molecular geometry and electrostatics. These are individually optimized to experimental pure fluid data on the vapor pressure and saturated liquid density, where the deviations are typically less than 5 and 0.5 %, respectively. The unlike dispersive interaction is optimized for seven of the nine studied binaries. Previously unpublished experimental binary VLE data, measured by BASF in the vicinity of ambient temperature, are predominantly used for these fits. VLE data, including dew point composition, saturated densities and enthalpy of vaporization, are predicted for a wide range of temperatures and compositions. © 2010 American Institute of Chemical Engineers AIChE J, 2011     

氯化液干燥器腐蚀分析和防护

分析了氯化苯氯化液干燥器的腐蚀原因、腐蚀状态及防范措施。     

紫外光-超声波耦合降解水溶液中苯酚和氯苯的研究

选取苯酚和氯苯分别作为亲水性和疏水性有机物代表,研究了紫外光、超声波和紫外光-超声波耦合3种降解方式、初始p H和初始浓度对苯酚和氯苯降解的影响。结果表明:苯酚紫外光降解效果更优,而氯苯超声波降解效果更优,两者耦合比单独使用降解效果更好。在中性条件下,苯酚的降解率最大;溶液的初始p H对氯苯降解率的影响不明显。2种有机物的降解与初始浓度呈负相关性,在同一浓度下,苯酚降解效果较优。     

萃取精馏分离甲醇-苯

采用萃取精馏的方法分离甲醇-苯的共沸物系。首先采用UNIFAC基团贡献理论并结合经验选取萃取剂,最终确定萃取剂为氯苯。对常压下甲醇 苯物系应用UNIFAC模型计算各组分的汽液相组成,并进行汽液平衡实验验证,计算结果与实验数据吻合较好。通过间歇萃取精馏实验进一步考察验证所选萃取剂的分离效果。结果表明,氯苯能够打破甲醇-苯的共沸,进而分离甲醇和苯。溶剂物质的量之比为1、回流比为3、填料塔理论板数为30、溶剂回收段理论塔板数为4时产品甲醇回收率达到98%,说明氯苯能够作为萃取剂分离甲醇-苯二元共沸物系。最后,对甲醇-苯物系的连续精馏过程应用Aspen Plus进行了模拟计算,并且考察了回流比、萃取剂进料流率等参数对产品纯度的影响规律,为进一步实验研究及工业应用提供理论和实践基础。     

五氧化二氮对氯苯的选择性硝化研究

对硝基氯苯是偶氮染料和硫化染料的重要中间体.本文研究了在HZSM-5分子筛催化下,五氧化二氮对氯苯的硝化反应.该方法通过改变硝化剂,不仅成功地避免了浓硫酸的使用,而且提高了原子经济性,具有良好的环境效益.实验考察了反应温度、反应时间,催化剂用量及Si/Al对反应结果的影响.研究表明,在最佳反应条件下,氯苯硝化反应得率达到70%,对位选择性为85%.     

氯化苯生产中氯化尾气爆鸣事故的原因和预防措施

分析了氯化苯生产过程中爆鸣事故产生的原因,提出了预防措施。     

低沸点溶剂加压催化热解制备六亚甲基-1,6-二异氰酸酯

以低沸点氯苯为溶剂,在加压条件下进行了六亚甲基-1,6-二氨基甲酸甲酯(HDC)液相催化热解制备六亚甲基-1,6-二异氰酸酯(HDI)的研究;通过TG-DTG技术对HDC热解过程进行了分析,筛选了催化剂,优化了工艺条件,并通过原位FTIR技术推测了HDC的催化热解机理。实验结果表明,HDC热解制备HDI分两步完成;优化的反应条件为:采用Co2O3催化剂、反应温度230℃、HDC含量为溶剂质量的2.5%、催化剂用量为HDC质量的5%、N2流量为600 mL/min、反应时间3 h,在此条件下,HDC的转化率可达100%、HDI收率可达83%左右。机理研究推测:Co2O3催化剂是通过进攻HDC的氨基甲酸甲酯基团上的C=O双键,最终使酯基断裂形成异氰酸根基团。     

SAMPLE MATRIX EFFECTS ON MEASUREMENTS OF CHLORINATED HYDROCARBONS USING A FIBER-OPTIC INFRARED SENSOR

The influence of sample matrix composition on the infrared sensing response to chlorinated hydrocarbons was investigated. The parameters of chemical oxygen demand (COD) and total organic carbon (TOC) were used to characterize water samples from natural and industrial waters. Chlorobenzene was selected as a model target for assessing the effect of the sample matrix, defined by their COD and TOC values, on the infrared optical measurements. It was found that it was possible to directly compare recovery values with TOC and COD values at low concentrations of the latter. However, where TOC and COD values were high, in particular for industrial waters, the influence of sorbing natural organic matter was low compared to the total organic carbon due to the synthetic component of the water. Therefore, when measuring natural environmental waters, it was possible to use COD and TOC values to obtain the true concentration of the analyte in the sample, but for industrial samples, the COD and TOC values were not good indicators.