二氧化碳和水对低温氧化铁脱硫的影响

Influence of CO_2 and Water Vapor on Desulfurization of Iron Oxide Sorbent at Low Temperature

以铁矾土、赤泥与石灰为原料,经机械混合法制备了氧化铁低温脱硫剂.采用热重法考察了工业气源中普遍存在的二氧化碳与水汽对氧化铁脱硫剂在80~120℃低温条件下对硫化氢脱除性能的影响.研究表明：二氧化碳对脱硫具有抑制作用,这主要是由于其与硫化氢在氧化铁表面存在竞争吸附所导致的.而水汽影响较为复杂,少量水汽因可在脱硫剂表明形成水膜,利于硫化氢在脱硫剂表面溶解吸附,因而会促进脱硫.但大量的水汽存在,也会对平衡产生影响,使得脱硫速率减慢.

Iron oxide sorbent for low temperature desulfurization was prepared by mechanical mixing method, using laterite, redmud and lime as raw materials. The influence of CO2 and water vapor, which generally existed in industrial gas stream, on the performance of HE S removal by iron oxide sorbent was investigated by thermogravimetric analysis, at low temperatures from 80℃ to 120℃. The results show that carbon dioxide inhibits desulfurization due to the competitive adsorption of HE S on the sorbent surface. The effect of water vapor on desulfurization is complex. Small amount of water vapor in gas stream is favorable to desulfurization because of the formation of water film in which HzS can be dissolved and absorbed easily. However, much water in stream will slow down the rate of desulfurization because of negative impact on the reaction equilibrium.