转化吸收型氧化锌基脱硫剂脱除H2S和COS性能

Performance of Conversion-Absorption ZnO Based Desulfurization Sorbents for Removing H2S and COS

摘要:

以前驱物工业活性ZnO和碱式碳酸锌分解的ZnO为脱硫剂活性组分，在引入结构助剂γ-Al2O3、碱性助剂K2CO3改性的基础上，制备出转化吸收型氧化锌基脱硫剂。在300 ℃、空速2000 h-1及常压下，考察了活性组分ZnO前驱物种类及不同前驱物制备的助剂γ-Al2O3对氧化锌基脱硫剂脱除硫化物性能的影响。结果表明：改性氧化锌基脱硫剂的孔隙结构和碱性显著影响其脱硫性能。与工业活性ZnO制备的氧化锌脱硫剂相比，以碱式碳酸锌分解的ZnO制备的脱硫剂对硫化氢的脱除效率和穿透硫容都更高，穿透硫容约增加10倍。不同前驱物制备的γ-Al2O3对氧化锌基脱硫剂脱硫性能有较大影响。其中，拟薄水铝石分解的γ-Al2O3显著提高了氧化锌基脱硫剂脱硫性能，穿透硫容达12.18%。以碱式碳酸锌分解ZnO为活性组分，添加拟薄水铝石分解的γ-Al2O3和碱性助剂K2CO3制备的改性氧化锌基脱硫剂对COS的脱除起到转化与吸收作用，COS转化率达99.98%，穿透硫容为4.03%。

Abstract:

A series of conversion-absorption ZnO based desulfurizers were prepared by using industrial ZnO and ZnO obtained by basic zinc carbonate decomposition as active component respectively, γ-Al2O3 as structure additive and K2CO3 as basic additive. The effects of ZnO precursors and γ-Al2O3 precursors on the desulfuration properties of prepared ZnO based desulfurizers were investigated at 300℃and atmospheric pressure with a gas space velocity of 2000 h-1. The results showed that the pore structure and basicity of ZnO based desulfurizers could significantly affect their desulfurization properties. The desulfurizer using ZnO obtained by basic zinc carbonate decomposition as the active component had high removal efficiency and good breakthrough sulfur capacity, and the breakthrough sulfur capacity was increases about 10 times comparing with that of the desulfurizer using industrial ZnO as the active component. In addition, the γ-Al2O3 prepared by different precursors had influences on the desulfurization properties of the prepared ZnO based desulfurizers. The γ-Al2O3 decomposed from pseudo boehmite obviously improved desulfurization properties of the desulfurizers, the breakthrough sulfur capacity was 12.18%. Among these desulfurizers, the desulfurizer using ZnO decomposed from basic zinc carbonate as the active component, γ-Al2O3 decomposed from pseudo boehmite as the structure additive and K2CO3 as the alkaline additive, could convert and absorb COS with a COS conversion of 99.98% and a breakthrough sulfur capacity of 4.03%.