Preparation Of Polystyrene Microspheres And Effect Of Texture On The Performance Of Hot Gas Desulfurizer

Coal is the most abundant fossil energy and chemical raw material in the world, especially in China. Integrated gasification combined cycle (IGCC) power generation process is considered to be the most promising clean coal technology for this century due to its high efficiency and low environmental pollution, in which removal of sulfur specics (mainly H2S) is crucial. Although hot coal gas desulfurization has been studied for many years, the commercialization of this technology has not been realized till now. The main obstacle is suggested to be the decrease of performance of desulfurizer. Texture has remarkable influence on the performance of desulfurizer. To prepare the sorbent with different texture characters, and to study the effect of texture on performance of sorbent, then thereby to improve the performance are the objective of this study.According to the reseach content of State Key Basic Reseach Development Program"973"project "Basic reseach on poly-generation application of syngas product from gasification gas and pyrolysis gas" (No.2005CB221203), polystyrene microspheres (PSt) with different diameter was synthesized, and hot gas desulfurization sorbents was prepared by using PS as pore-forming material. The evaluations of the sorbents were conducted in a fixed-bed reactor, and the effects of texture on the performance of sorbents were investigated by XRD, SEM and mercury intrusion techniques.The experiments results show that polymerization and soap-free emulsion polymerization could be used for synthesis of uniform polystyrene microspheres. The former were used for the preparation of polystyrene microsphere with diameters less than 100nm and, whereas the later is more suitable for synthesis of polystyrene microsphere with diamer rang from 350-550nm.The sorbents with different textural for hot gas desulfurization was prepared by a solid mixed method using red-mud form steel factory as the activate component, PS as pore-forming materials and clay as binder. The prepared sorbents were evaluated in a fixed bed reactor in simulated coal gas atmosphere at the temperature of 500℃,2000 h-1.It was found that texture have a significant impact on desulfurization performance. The breakthrough sulfur capacity was different as the texure charaters of sorbent changed. The pore with diameter of around 200nm is not only favorable for sulfer capacity but also beneficial for the stability of the sorbent during the cycles.The effect of steam content and pre-reduction on desulfurization in simulated coal gas were also investigated.