共沉淀法制备铁锌基中高温煤气脱硫剂

Preparation of zinc ferrite-based sorbent using coprecipitation method for medium-high temperature coal gas desulfurization

采用共沉淀法制备Cu-Zn-Fe脱硫剂,优化共沉淀制备工艺。固定床实验结果表明,共沉淀溶液中金属离子总浓度为0.6 mol/L,焙烧温度600℃,添加10%活性助剂Cu时所得Cu-Zn-Fe脱硫剂循环脱硫性能最佳,此时ZFDCu10脱硫剂的硫容可达到41.2 g S/100 g脱硫剂。XRD和SEM对铁锌基脱硫剂的表征结果表明,加入Cu助剂后少量的ZnO、CuO可阻碍ZnFe2O4晶粒聚集,增强铁锌基脱硫剂活性组分的分散性,避免大晶粒的ZnFe2O4硫化时形成较多的产物层而降低脱硫剂的利用率。实验结果为制备脱硫性能较好的Cu-Zn-Fe脱硫剂提供了理论依据。

Cu-Zn-Fe regenerable sorbents were prepared and optimized by coprecipitaion method. The per- formance of sorbents was tested using a fixed-bed reactor, and the results indicated that the sorbent exhibited a high sulfur capacity of 41.2 g S / 100 g sorbent under conditions： the total metal ion concentration of 0.6 mol/ L, the calcination temperature of 600℃ , and the additive of 10% Cu. The results of XRD and SEM showed that the assistance Cu could prevent the aggregation of ZnFe2O4 crystals with the presence of a little ZnO and CuO, improve the dispersion of the active ZnFe2O4 component, and avoid the formation of more product layers which would result the lower utilization of the desulfurizer. The experimental results provide a theoretical basis for the preparation of Cu-Zn-Fe sorbents with good desulfurization performance.