Risk Analysis For Traditional Process Of Propylene Glycerol And Study On Green Catalysis Synthesis

1,2-propandeiol is an valuable downstream commodity chemical which is proverbially used in the manufacture of some industrially essential chemicals such as polymers, functional fluids, pharmaceuticals, cosmetics. 1,2-PDO is also an important chemicals widely used as solvent, printing ink, etc. Further there is increasing demand for 1,2-propandeiol due to its non-toxic nature and extensive applications. Propylene glycerol traditionally produced from hydration of petroleum-derived propylene oxide which brings serious environmental problems and energy consumption. Increasing attention has been paid to the hydrongenolysis of glycerol that it could be a economically competitive and environmentally attractive method to produce 1,2-PDO as its abundant stocks and simply process. According to the material and process risk, analyzing the risk of the method that preparing propylene glycol by hydration process of propylene oxide. In accordance with the requirements of inherent safety principles and the clean production technology, as far as possible avoid dangerous matter from propylene glycol in the production process, through the improvement design and optimization process, using safe materials instead of hazardous materials and other comprehensive measures to research the supported type magnetic catalyst catalyzes hydrogenolysis of glycerol to synthesis propylene glycol. The process can reduce their risk from the source, not by additional security measures to control the risk. Through the use of non-toxic or less toxic materials and mild process conditions, the safety function will be integrated into the production process, and also can avoid the occurrence of accidents and achieve intrinsic safety.Hydrogenolysis of glycerol to 1,2-propanediol is one of the most promising routes which can effectively improve the economic benefit of biodiesel manufacturers. Several Ru-Cu bimetallic catalysts supported on titania-iron oxide were prepared by co-impregnation method and were evaluated for the hydrogenolysis of glycerol. The as-prepared catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and N2 adsorption. The effects of Ru/Cu atomic ratio, reaction temperature, H2 pressure, reaction time and catalyst amount on the catalytic performance were investigated. The Ru-Cu/Fe₃O₄-TiO₂ and Ru-Ni/Fe₃O₄-ZrO₂ bimetallic catalyst all showed high activity and good selectivity to 1,2-propanediol. Under the optimized conditions（Ru/Cu = 1:1.6, 200 ℃, 4.0 MPa, and 10 h）, the conversion of glycerol and the selectivity to 1,2-propanediol reached 96.12% and 86.77%, respectively. The magnetic catalysts and reaction products can be easily separated by an external magnetic field, which is beneficial to the industrialization of this process.In this paper, the overall consideration of the material risk and the risk that the process of propylene glycol, and the evaluation model of the essential safety degree of the chemical process is established. The hydration process of propylene oxide and the process of catalytic hydrogenation of glycerol were evaluated. By calculating the potential hazard index, it was concluded that the essential safety degree of the glycerol catalyzed hydrogen hydrolysis process was higher than that of the conventional propylene oxide water method. Supported magnetic catalyst for the preparation of propylene glycol by catalytic hydrogenation of glycerol to achieve a more efficient, more economical and lower energy consumption than the traditional technology.