改性活性炭水解COS催化剂的再生方法

Regeneration of modified activated carbons used as COS hydrolysis catalysts

采用BET,SEM和XPS等技术,研究用于COS水解反应的活性炭(AC)负载Fe-Cu催化剂在固定床反应器中的失活与再生行为,重点考察水洗再生、N2热再生以及热再生温度对Fe-Cu/AC催化水解COS活性的影响。研究结果表明:水洗再生虽能洗去反应过程中沉积在催化剂表面的部分可溶性含硫物质,但同时可将表面的碱性基团洗去,使催化剂的水解活性降低;经99.99%N2热再生,催化剂的脱硫活性较强,活性恢复较理想;当再生温度为250～300℃时,催化剂表面的硫酸盐基本被除去,只有少量的单质硫存在;此外,采用N2热再生法可实现Fe-Cu/AC催化剂的多次再生,大大降低了工艺成本。

The activated carbon supported Fe-Cu catalyst used for COS hydrolysis was prepared by gel precipitation method and characterized by BET,SEM and XPS techniques.The activity evaluation of COS hydrolysis over the catalyst was conducted in a fixed-bed reactor.The regeneration performance of the used Fe-Cu/AC catalyst was investigated using different methods.The results show that water-washing can flush away part of the dissolved sulfur-containing compounds on the surface of the catalysts,but it simultaneously causes the loss of a considerable amount of basic groups,consequently resulting in the decrease of the activity of the catalyst.Thermal regeneration by 99.99% N2 can remove the most sulfates,only leaving a very small amount of element sulfur in the catalyst surface.The Fe-Cu/AC catalyst can be regenerated by thermal N2 several times,which shows good regeneration performance and great decrease of the industrial production cost.