双氧水—丙烯—甲醇体系的相态研究

钛硅分子筛催化丙烯环氧化是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.采用可视相平衡仪对不同氧化剂体系（50％双氧水体系和30％双氧水体系）、不同温度（30～80℃）、不同压力（0.8～3.5 MPa）、不同物料配比甲醇∶双氧水（摩尔比）为5～20,丙烯∶双氧水（摩尔比）为1～4]的进料体系进行了相态观测.结果表明,丙烯进料量和甲醇含量是影响体系相态的关键因素.在相同物料配比和相近的丙烯进料量下,50％双氧水体系比30％双氧水体系液相更易达到均相.此外,对于两种双氧水-丙烯-甲醇体系,甲醇含量一定时,丙烯的进料量越小,体系液相越易呈均相状态.总之,为了使丙烯和双氧水能在液相中充分接触,应使丙烯进料量接近体系温度、压力下丙烯在双氧水-甲醇溶液中的饱和溶解度.

Phase Behavior Investigation of Hydrogen Peroxide-Propylene-Methanol System

Catalytic propylene epoxidation on titanium silicon molecular sieve is a green process for produc- tion of propylene epoxide,and the phase behavior of the multiphase reaction system is the foundation to opti- mize this reaction. Visual phase equilibrium apparatus has been used for phase behavior observation under fol- lowing conditions： oxidant systems with 50% hydrogen peroxide or 30% hydrogen peroxide,different tempera- tures（30-80 ℃）,different pressures（0. 8- 3.5 MPa）, different material molar ratios （methanol to hydrogen peroxide.5-20,propylene to hydrogen peroxide： 1-4）. The research results show that the propylene feeding quantity and the content of methanol are the key influencing factors for the system liquid phase. With the same material ratios and similar propytene feeding quantity,system with 50% hydrogen peroxide is easier to achieve homogeneous because of the higher amount of methanol. In addition, with a certain content of methanol, the system liquid phase is easier to present homogeneous with the smaller propylene feeding quantity for＇two hy- drogen peroxide-propylene-methanol systems. In a word, for the sufficient contact between propylene and hy- drogen peroxide,the propylene feeding quantity should be close to its saturate solubility in hydrogen peroxide- methanol at system temperature and pressure.