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题名	二苯甲烷二氨基甲酸甲酯热解过程基础研究
作者	张琴花
学位类别	硕士
答辩日期	2011-05-15
授予单位	中国科学院研究生院
导师	李会泉 ; 柳海涛
关键词	二苯甲烷二氨基甲酸甲酯 二苯甲烷二异氰酸酯 动力学 热分析
其他题名	Basic Research of MDC Thermal Decomposition Processes
学位专业	化学工艺
中文摘要	二苯甲烷二异氰酸酯(MDI)是一种重要的有机化工原料，工业上主要采用光气法生产。随着环保要求的日益强烈，发展非光气清洁路线制备MDI正在成为异氰酸酯行业领域绿色化学化工的前沿。本文对非光气制备MDI的关键过程—二苯甲烷二氨基甲酸甲酯(MDC)热分解制备MDI过程，开展了热分解本征、表观及产物MDI聚合动力学的系统研究，建立了热分解过程中各物种的分析方法，得到热分解体系的动力学参数与模型，研究结果可为最佳反应条件确定、工业反应器设计及优化提供理论依据。主要研究内容与进展如下： (1)、完成了MDC热分解历程研究。通过TG-FTIR联用技术对MDC热分解过程中释放气体进行实时跟踪检测，以及实时取样对体系中各物质实现定量分析。研究结果表明：MDC热分解过程首先释放一分子甲醇生成中间体4-(4'-苯氨基甲酸甲酯)苯甲烷异氰酸酯(MMI)；而后MMI继续分解释放甲醇得到产品MDI(失重量大于15%)，MDI会发生聚合并放出CO2气体； (2)、完成了MDC热分解本征动力学研究。根据MDC热分解的TG/DSC/DTG数据，采用Kissinger、Flynn-Wall-Ozawa、Coats-Redfern及Satava-Sestak法计算，建立了MDC-MDI热分解本征动力学方程，其活化能为129.99kJ/mol，指前因子为1.303×1013min-1，其热分解机理满足随机成核和随后生长模型； (3)、完成了MDC-MMI-MDI热分解表观动力学研究。根据均相反应动力学理论，利用液相色谱实现MDC热分解过程中各物质的定量分析，对MDC的消耗速率及MDI的生成速率进行拟合，分别得到连串热解反应表观动力学方程，相应的活化能为138.82kJ/mol、167.78kJ/mol，指前因子为1.51×1012min-1，5.33×1014min-1； (4)、完成了MDI聚合动力学研究。根据MDI聚合的TG/DSC/DTG数据，采用Flynn-Wall-Ozawa、Coats-Redfern及Satava-Sestak法计算，建立了MDI聚合动力学方程，其活化能为58.42kJ/mol，指前因子为5006min-1，其聚合机理满足随机成核和随后生长模型。
英文摘要	Methylene diphenyl-4, 4’-diisocyanate (MDI), which is major raw material, is mainly synthesized through phosgene route in the industrial production. For the extreme toxicity of phosgene and serious pollution caused by the co-product HCl in the phosgene method, significant attempts have been made to develop non-phosgene routes, among which, thermal decomposition of Methylene Diphenyl Dicarbamate (MDC) to obtain MDI has been thought to be one of the most attractive ways. Some key issues of the thermal decomposition of MDC to synthesize MDI of the non-phosgene route were systematically researched in the dissertation. The achievements and progresses were exhibited as follow: (1) To qualitative and quantitative analysis the substances of the MDC decomposition system by real-time sampling; Fourier Transform infrared technique was used to identify evolved gases. The result showed that the intermediate product methylene-4-(4'-methylphenylcarbamate) phenylisocyanate (MMI) was produced firstly, and then, MDI was manufactured by the thermal decomposition of MMI. The main gas identified from the spectra was methanol during the decomposition of MDC and carbon dioxide during the polymerization of MDI; (2) The thermal behavior and decomposition kinetics of Methylene Diphenyl Dicarbamate (MDC) were investigated by thermogravimetry/differential scanning calorimetry/derivative thermogravimetry in nitrogen gas flow. Fourier Transform infrared technique was used to identify evolved gases. The activation energy values of the decomposition step were estimated by the isoconversional method of Kissinger and Flynn-Wall-Ozawa methods, and the possible conversion function had been estimated through the Satava-Sestak and Coats-Redfern methods. The activation energies and pre-exponential factor are 129.99kJ/mol and 1.303×1013min-1; (3) The kinetics study of MDC to MDI was investigated in the presence of solvent. A consecutive reaction model was established by simplifying the decomposition process and the two steps were conformed to be the first-order by integral test model and numerical differential method, respectively. Base on the obtained kinetic model, the reaction proceeding can be calculated in given conditions; (4) The polymerization processes of Methylene Diphenyl Diisocyanate (MDI) had been studied in flow atmosphere of high purity N2 using TG-DSC-DTG techniques. The kinetic parameters of the polymerization process were calculated through the Flynn-Wall-Ozawa method and the polymerization mechanism of MDI was also studied with the Satava-Sestak and Coats-Redfern methods. The activation energies and pre-exponential factor are 58.42kJ/mol and 5006min-1.
语种	中文
公开日期	2013-09-24
页码	87
内容类型	学位论文
源URL	[http://ir.ipe.ac.cn/handle/122111/1744]
专题	过程工程研究所_研究所（批量导入）
推荐引用方式 GB/T 7714	张琴花. 二苯甲烷二氨基甲酸甲酯热解过程基础研究[D]. 中国科学院研究生院. 2011.

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