低浓度煤矿抽采瓦斯液相一步法合成甲醇动力学及热力学研究

Comprehensive utilization of drained coal mine gas is restricted by a lot of factors such as unstable gas concentration, lack of utilization technology，and so on, a large amount of gas is vented into the atmosphere during coal mining period, therefore,a new technology for utilization of low concentration mine gas should be exploited urgently . So, a research thought that one-step synthesis of methanol in liquid phase from low concentration mine gas is presented in this research project. Based on the method of combining theoretical analysis, experimental research with Gaussian simulation, kinetics and thermodynamics of one-step synthesis of methanol in liquid phase from low concentration mine gas are studied. Controllable catalyst of low concentration mine gas conversion is prepared by means of selecting iodine, iodine series compounds, compounds of transition metal such as Cu ,Fe,Co,Ni and V as raw materials that have catalytic activity for methane; kinetics of one-step synthesis of methanol from mine gas is studied in high pressure experimental system on condition that typically low concentration mine gas with less than 30% concentration serves as raw gas and oleum serves as reaction solvent, and macrokinetics model is obtained; The influence law of methane conversion caused by other components in low concentration mine gas is revealed on the basis of mass transfer theory;Thermodynamic analysis for the liquid partial oxidation of low concentration gas in oleum is carried out using Gaussian, and reaction mechanism and controlling step of affecting selective oxidation of low concentration gas to methanol are revealed. The project has important significance for improving utilization of drained gas, preventing gas accident and reducing greenhouse effect due to gas discharging.

煤矿抽采瓦斯浓度不稳定、利用技术缺乏等因素制约了其综合利用，放空现象严重，急需开发低浓度瓦斯利用新技术。项目提出以低浓度瓦斯为原料直接合成甲醇的研究思路，采用理论分析、实验研究、Gaussian模拟相结合的方法开展低浓度瓦斯液相一步法合成甲醇动力学及热力学研究。筛选对甲烷具有催化活性的碘单质、碘系化合物以及Cu、Fe、Co、Ni 、V等过渡金属的化合物，制备低浓度瓦斯可控转化催化剂；以甲烷浓度低于30%的典型低浓度瓦斯为原料气，以发烟硫酸为溶剂，利用高压实验系统研究低浓度瓦斯液相一步法合成甲醇动力学，建立宏观动力学模型；基于传质理论，揭示甲醇合成过程中低浓度瓦斯中其它组分对甲烷组分转化的影响规律；通过对低浓度瓦斯液相合成甲醇热力学性质进行Gaussian模拟，阐明反应机理和影响反应的控制步骤。项目研究对提高抽采瓦斯利用率、防治瓦斯事故、减少因瓦斯排放引起的"温室效应"具有重要意义。

瓦斯是一种优质的气态燃料和化工原料，同时也是煤矿井下开采的灾害因素以及造成大气温室效应的一个重要有害源。随着人们对煤矿安全、环境保护意识的提高，近年来国内外十分重视瓦斯的开发利用。本项目以低浓度瓦斯为原料进行液相一步法合成甲醇的技术研究。制备了Fe2O3/ZSM-5、CuO/ZSM-5、Fe2O3-CuO/ZSM-5等非贵金属催化剂和Ag2SO4、Pt(bipy)Cl2、Pd(bipy)Cl2等贵金属催化剂以及构建了3%Pd/C-四氯对苯醌-CO、Pd(OAc)2-四氯对苯醌-CO两种催化剂体系，分别以醋酸和发烟硫酸为溶剂，对甲烷浓度20～25%的瓦斯进行了直接合成甲醇的实验研究。考察了反应温度、反应压力、反应时间、催化剂用量等动力学因素对低浓度瓦斯直接催化氧化合成甲醇的影响，研究了低浓度瓦斯液相一步法合成甲醇动力学，建立了宏观动力学模型；对低浓度瓦斯部分氧化反应过程进行了量子化学模拟，揭示了低浓度瓦斯转化为目标产物的主要途径；阐明了低浓度抽采瓦斯液相催化氧化合成甲醇的反应机理。本项目任务书拟发表学术论文8~10篇，实际发表论文11篇（其中，EI收录5篇），出版专著1部，授权专利2项。