流化床甲烷临氧CO_2自热重整制合成气研究

采用分步浸渍方法,制备了高分散的Ni/MgO-SiO2催化剂,并在固定床和流化床反应器中对该催化剂用于甲烷临氧CO2自热重整制合成气反应进行了评价。反应结果表明,催化剂在两种反应器中均表现出接近热力学平衡的初活性;随着空速的变化及反应时间的延长,催化剂的活性在两种反应器中表现出明显的差异。采用TEM测试手段对反应后的催化剂进行表征。结果表明,流化床反应器对反应过程、消除积碳及控制活性组分晶粒烧结有较明显的促进作用。与固定床反应器相比,流化床反应器是适合甲烷临氧CO2自热重整制合成气的反应器。

Study of Autothermal CO2 Reforming of Methane with O2 to Produce Syngas in Fluidized Bed and Fixed Bed Reactor

Highly dispersed Ni/MgO-SiO2 catalysts were prepared by successive impregnations, and autothermal CO2 reforming of methane in presence of Q2 was carried out in both fluidized and fixed bed reactors. Initial catalytic performance approaching thermodynamic equilibrium was obtained in both reactors; however, catalytic reactivity diversified in two types of reactors along with on stream time or changing of space velocity. The fresh and spent catalysts were characterized by means of TEM technique. From TEM carbon in manner of whisker was found on catalyst from rear part of fixed bed reactor and no deposited carbon was observed on catalyst in fluidized bed reactor after reaction. Fluidization of catalyst particles in fluidized bed reactor favored inhibiting deposition of carbon and a thermal uniformity in reactor. Fluidized bed reactor was in principle a suitable reactor for autothermal CO2 reforming of methane in presence of oxygen to produce synthesis gas.