基于金属氧化物脱硫剂的天然气深度脱硫

Deep desulfurization of natural gas with metal oxide desulfurizers

确立了基于GC-MS和GC-SCD的天然气中超微量硫化物定性定量分析方法与条件,并分析了北京城市天然气中的硫化物。结果表明,天然气中含有三种硫化物,主要成分为四氢噻吩（THT）,占总硫的94.2%。采用共沉淀法制备了ZnO/Al2O3脱硫剂,采用浸渍法制备了ZnO/γ-Al2O3、CuO/γ-Al2O3和CuO-ZnO/γ-Al2O3脱硫剂,并进行了天然气中THT深度脱除的实验研究。结果表明,采用浸渍法制备的CuO/γ-Al2O3和CuO-ZnO/γ-Al2O3脱硫剂同时具有良好的低温活性和高温活性,可在50~500℃的宽温下将THT脱除至物质的量分数10×10-9以下,从而能够满足以天然气为燃料的分布式质子交换膜燃料电池电站对脱硫深度和脱硫温宽的要求。

Qualitative and quantitative analysis methods for ultra trace sulfides in natural gas were established based on GC-MS and GC-SCD, and utilized to determine the sulfides in the domestic natural gas of Beijing. The results indicate that the natural gas contains three kinds of sulfides, and the main component accounting for 94.2% is tetrahydrothiophene （THT）. ZnO/A1203 was prepared by co-precipitation, and ZnO/γ/-A1203, CuO/ γ-A1203 and CuO-ZnO/7-A1203 were prepared by impregnation. Experimental research on the deep removal of THT in the city natural gas was carried out with these desulfurizers. It is found that THT can be removed to less than 10×10^-9（ molar fraction）with CuO/γ/-A1203 and CuO-ZnO/γ/-A1203 in a wide temperature range from 50 500℃, which can meet the requirements of desulfurization depth and working temperature width for distributed PEMFC power station based on natural gas.