高强度A110-5Q型氨合成球形催化剂物理化学性能的研究

本文报道了高强度A110-5Q型氨合成球形催化剂的各种密度、抗压强度、比表面、孔结构、催化活性、动力学参数以及穆斯堡尔谱对物相的研究等.结果表明高强度球形催化剂的氧化态结构紧密,孔隙细小,堆密度和颗粒密度提高10—12%.还原态平均孔半径和最可几孔径增大,出现三个微孔体系,比表面仍在9m~2/g以上.实现了抗压强度提高约一倍、保持了高活性低阻力等优良性能.动力学参数指前因子K.和活化能E均有增大,K_o和E遵从补偿效应关系.K_o增大两个数量级与孔结构变化有关.

Physico-Chemical Properties of High Strength Spherical Catalyst A110-5Q for Ammonia Synthesis

Various physico-chemical properties of high strength spherical catalyst A110-5Q, i. e., the densities, porosity, void fraction, specific pore volume, crushing strength and Mossbauer spectroscopy in the oxidized state, and the porosity, specific pore volume, specific surface area, average pore radius, pore size distribution, catalytic activity and kinetic parameters in the reduced state have been studied.In the oxidized state the crystal grains of the high strength catalyst with pore size of-1000A are packed more closely and the bulk and particle densities are 10-12% higher than those of the low strength catalyst with pore size of 1-5μm. In the reduced state the average pore radius and the most probable pore radius in the high strength catalyst are larger than those in the low strength catalyst, and there are three systems of pores in the former. Besides a twofold increase of the crushin gstrength, the high strength catalyst still maintaisn high activity and low flow resistance. The values of freuqency factor(ko)and activation energy(E) for ammonia synthesis are higher than those of the low strength spherical catalyst and the compensation effect equation, lnko = B+ f·E, applies.