Bimetallic Mercaptan Conversion Catalyst for Sweetening Liquefied Petroleum Gas at Low Temperature

摘要

The present invention relates to a bimetallic mercaptan conversion catalyst for sweetening liquefied petroleum gas at a low temperature, which is prepared by using an Al2O3—SiO2 composite oxide as a carrier to support bimetallic active components vanadium and nickel. The bimetallic mercaptan conversion catalyst has a proper specific surface area and more metal active center sites, and has advantages of simple preparation, an efficient mercaptan conversion ability even at a low temperature, and causing no saturation and polymerization of olefins. The bimetallic mercaptan conversion catalyst exhibits superior mercaptan conversion performance in LPG sweetening, has strong adaptability to starting materials, and can also nearly completely remove trace carbonyl sulfide contained in LPG.

主权项

1. A method for preparing a bimetallic mercaptan conversion catalyst for sweetening liquefied petroleum gas at a low temperature, comprising the following steps:
(1) mixing 60-80 parts by mass of aluminum hydroxide xerogel and 20-40 parts by mass of silica xerogel uniformly, adding a pore-forming agent and an aqueous nitric acid solution thereto, followed by mixing and kneading, and then extruding the resultant to produce a formed article; (2) air-drying the formed article by placing it at room temperature for 8-15 hours, drying it at 90-120° C. for 3-5 hours, then calcinating it for 3-8 hours by elevating the temperature to 450-620° C. at a heating rate of 2-4° C./min, and subsequently crushing and screening the resultant to produce short-rod-like particles having a size of 4-6 mm, thereby producing an Al2O3—SiO2 composite oxide carrier; and (3) loading bimetallic active components, vanadium and nickel, separately onto the Al2O3—SiO2 composite oxide carrier by using an isometric impregnation method, and then drying and calcinating it to obtain the bimetallic mercaptan conversion catalyst for sweetening liquefied petroleum gas at a low temperature.