钛包裹铁锰钛复合氧化物催化剂SCR脱硝及抗SO_(2)中毒性能优化研究

Promotional Modification on the NH_(3)-SCR Activity and Anti-SO_(2)Poisoning of Fe-Mn-Ti Mixed Oxide Catalyst by Ti Cladding and Ce/W Doping

利用溶胶-凝胶法构筑了钛包裹铁锰钛复合氧化物核壳结构催化剂,研究了铈、钨掺杂对核壳结构催化剂脱硝性能和抗SO_(2)中毒的影响。研究发现:高比例包裹钛会降低铁锰钛复合氧化物SCR脱硝性能,但可提高Mn_(45)Fe_(45)Ti_(10)O_(z)抗SO_(2)中毒性能,且Ti_(100)@Mn_(45)Fe_(45)Ti_(10)O_(z)脱硝效率比Ti_(100)@Mn_(50)Fe_(50)O_(z)高5%~10%;钛壳低摩尔比铈、钨掺杂可提高Ti_(100)@Mn_(45)Fe_(45)Ti_(10)O_(z)催化剂脱硝性能和抗SO_(2)中毒性能,壳层合适的Ti∶Ce∶W摩尔比为90∶5∶5;SO_(2)作用条件下,Ti_(90)Ce_(5)W_(5)@Mn_(45)Fe_(45)Ti_(10)O_(z)催化脱硝效率高于Ti_(100)@Mn_(45)Fe_(45)Ti_(10)O_(z)。

Titanium oxide was packaged on the surface of Fe-Mn-Ti mixed oxide core via sol-gel,and cerium or/and tungsten were used as the additives to modify titanium oxideshell in order to promote its catalytic performance and anti SO_(2)poisoning.The results indicate that the high molar ratio of packagedtitanium oxide decreases the NH3-SCR activity of Fe-Mn-Ti mixed oxide core,but improves its anti SO_(2)poisoning.And Ti_(100)@Mn_(45)Fe_(45)Ti_(10)O_(z)exhibits approximately 5~10 percents of NOx conversions higher than those of Ti_(100)@Mn_(50)Fe_(50)O_(z).The doping of lower cerium or/and tungsten additives into titanium shell increases the catalytic performance and the anti SO_(2)poisoning of Ti_(100)@Mn_(45)Fe_(45)Ti_(10)O_(z),and the suitable molar ratio of Ti∶Ce∶W is 90∶5∶5.In addition,Ti_(90)Ce_(5)W_(5)@Mn_(45)Fe_(45)Ti_(10)O_(z)shows better catalytic performance of NOx reduction than Ti_(100)@Mn_(45)Fe_(45)Ti_(10)O_(z)under the reaction condition of 100 ppm SO_(2).