Prepn and application of nickel-based catalyst for decomposing ammonia to prepare mixed H2-N2 gas

Abstract

The catalyst includes Ni as main active component; carrier SiO2 or Al2O3; and one or several selected from IA, IIA, IIIB, VIII or RE element Li, K, Mg, Y, Fe, Co and La as assistant. The preparation process includes soaking the carrier with solution containing Ni and assistant; and drying and roasting the soaked carrier. At the temperature of 650 deg.c and ammonia feeding space velocity of 12000 / hr, the residual ammonia in the tail gas may be controlled below 400 ppm. Compared with available Ni-base catalyst, the present invention has ammonia discomposing temperature lowered by 150 deg.c, catalyst loading amount lowered to 1 / 20, greatly reduced apparatus volume, obviously reduced residual ammonia amount in tail gas, 1 / 3 to 1 / 2 lowered power consumption, and obviously lowered apparatus cost and production cost.

Description

technical field [0001] The invention relates to a catalyst for ammonia decomposition to produce hydrogen-nitrogen mixed gas. [0002] The present invention also relates to a preparation method of the above-mentioned catalyst. Background technique [0003] Ammonia decomposition catalysts are mainly used in the field of environmental protection and the fields of reducing gas and protective gas. In the field of environmental protection, the ammonia contained in refinery gas and coke oven gas is usually decomposed into a non-toxic mixture of hydrogen and nitrogen through an ammonia decomposition catalyst for recycling or discharge to reduce environmental pollution; In the field of reducing gas and protective gas, the hydrogen-nitrogen mixed gas produced by catalytic decomposition of ammonia can be further separated to produce pure hydrogen, and can also be directly used as reducing gas or protective gas and widely used in float glass, powder metallurgy, electronics and other in...

AI Technical Summary

Problems solved by technology

Although the existing nickel-based ammonia decomposition catalyst has the advantages of good stability compared with iron-based catalysts, there are still problems such as high ammonia decomposition temperature, high energy consumption, and small catalyst processing capacity per unit volume, resulting in huge equipment, operating costs and equipment manufacturing costs. High, high decomposition temperature causes high energy consumption of equipment, easy to corrode and other disadvantages