表征及甲烷燃燒催化性質(zhì)
崔大立， 黃小衛(wèi)
( 北京有色金屬研究總院 有研稀土新材料股份有限公司， 北京 100088)
摘 要: 采用檸檬酸發(fā)泡法制備了鈣鈦礦LaCoO3催化材料;研究了Ce對La進(jìn)行摻雜替代對催化材料性能的影響；通過BET、 XRD、 SEM等手段對催化材料進(jìn)行了物性表征； 以甲烷完全燃燒為目標(biāo)反應(yīng)， 研究了鈣鈦礦La1-xCexCoO3+δ的催化性能。 結(jié)果表明： 鈰摻雜對材料晶相有較大影響， 當(dāng)摻雜量x小于0.3時， 粉體晶型基本不變， 而當(dāng)摻雜量達(dá)到0.5時， 有明顯CO3O4晶相出現(xiàn)， LaCoO3鈣鈦礦晶相完整性遭到破壞， 當(dāng)摻雜量大于0.7時， 鈣鈦礦晶相大大弱化甚至消失； LaCoO3是一種性能優(yōu)良的甲烷燃燒催化材料， Ce的摻雜替代對催化材料活性有明顯影響， 并增強了催化材料的高溫穩(wěn)定性能， 鈰最佳摻雜量為0.3； 前驅(qū)體經(jīng)700 ℃焙燒形成了較為完整的鈣鈦礦晶型， 經(jīng)800 ℃焙燒后， 催化材料最高活性為： t10%=390 ℃, t90%=603 ℃。
關(guān)鍵字: 檸檬酸; 鈣鈦礦; 甲烷; 催化燃燒; 稀土
La1-xCexCoO3+δ perovskite catalyst and its methane catalytic combustion
LONG Zhi-qi, CUI Da-li, HUANG Xiao-wei
（ Grirem Advanced Materials Co. Ltd,
General Research Institute for Non-ferrous Metals, Beijing 100088, China）
Abstract: Perovskite oxides LaCoO3 methane catalytic materials were prepared with citrate complexation and bubbling method. The cerium doping effect was studied in series La1-xCexCoO3+δ materials by BET, XRD and SEM techniques. And their catalytic behaviours were also studied with methane catalytic complete combustion as probe reaction. The results show that doped cerium has great effects on the crystal phase formed. When doped cerium content x is less than 0.3, the phases of powders are little changed. When doped cerium x is up to 0.5, obvious Co3O4 phase is discovered, and the integrity of LaCoO3 perovskite crystal phase is broken. When x is over 0.7, perovskite crystal phase is greatly weakened or completely disappeared. Considering the crystal phase of powders, the optimum cerium doping content is about 0.3. Perovskite oxides LaCoO3 are good methane catalytic materials. Doping cerium has some positive activity effect and the thermal stability of the material is also enhanced. The perovskite oxide can be formed at lower calcination temperature, about 700 ℃, and when x is 0.3, the best catalytic activity is acquired as t10%=390 ℃ and t90%=603 ℃ in series of La1-xCexCoO3+δ materials calcinated at 800 ℃.
Key words: citric acid; perovskite; methane; catalytic combustion; rare earth
