丙烯在甲醇-双氧水中的溶解度

钛硅分子筛催化丙烯环氧化是一条生产环氧丙烷的清洁工艺,其多相反应体系的相态研究是优化该反应体系的基础.利用可视相平衡仪在不同条件下测量了丙烯在甲醇-双氧水中的溶解度.结果表明,体系温度、双氧水有效质量浓度和甲醇含量是影响丙烯溶解度的关键因素.在双氧水∶丙烯∶甲醇摩尔比一定、温度相同且体系均为气-液-液三相平衡的条件下,30％（质量分数）双氧水氧化体系甲醇相中丙烯的溶解度低于50％（质量分数）双氧水氧化体系.在双氧水有效含量不同的两种氧化体系中,当甲醇含量较低时,体系呈现为气-液-液三相平衡,在30～60℃范围内可通过升温提高丙烯的溶解度;提高甲醇含量到一定程度时,体系液相在较低的温度下即可呈均相,为丙烯环氧化提供良好的反应环境.

Solubility of propylene in methanol-hydrogen peroxide

Catalytic propylene epoxidation on titanium silicon molecular sieve is a green process for production of propylene oxide,and the phase behavior of the multiphase reaction system is the foundation to optimize this reaction.Visual phase equilibrium apparatus was used for the propylene solubility measurement in methanol-hydrogen peroxide under different conditions.The research results show that system temperature,hydrogen peroxide concentration （the mass fraction of H2O2 in hydrogen peroxide solution） and the methanol content are the key factors to the propylene solubility; the propylene solubility in hydrogen peroxide-methanol of 30％ hydrogen peroxide system is less than that of 50％ hydrogen peroxide system when the 50％ hydrogen peroxide system and 30％ hydrogen peroxide system have the same materials molar ratio and the same system temperature,and both the two systems present a gas-liquid-liquid phase equilibrium system; moreover,for the hydrogen peroxide （50％ or 30％）-propylene-methanol system,when the feed methanol content is low,the solubility of propylene is improved by raising the temperature with 30-60 ℃ ; while when the methanol content is higher enough,the system liquid phase could be experienced as homogeneous with high propylene solubility at lower temperature,which provides a good reaction circumstance for the epoxidation of propylene.