(1.東北大學(xué) 材料與冶金學(xué)院, 沈陽 110006;
2.沈陽化工學(xué)院 化工系, 沈陽 110021)
摘 要: 在固定床反應(yīng)器中,用空氣焙燒HDS失活催化劑,再用碳酸鈉水溶液浸取釩和鉬。研究了釩焙燒轉(zhuǎn)化率隨失活催化劑粒徑、焙燒溫度及焙燒時間的變化關(guān)系,結(jié)果表明:實(shí)驗(yàn)數(shù)據(jù)可以用收縮未反應(yīng)核模型擬合。當(dāng)催化劑平均粒徑小于60μm,或在較低反應(yīng)溫度及較低轉(zhuǎn)化率下,內(nèi)擴(kuò)散阻力可以忽略不計(jì),過程受化學(xué)反應(yīng)控制;而當(dāng)平均粒徑大于60μm,且在較高反應(yīng)溫度及較高轉(zhuǎn)化率下,過程同時受化學(xué)動力學(xué)與內(nèi)擴(kuò)散控制。分別導(dǎo)出了2種情況下焙燒釩的動力學(xué)方程式,并按方程式計(jì)算得到反應(yīng)溫度在923~1123K時的活化能為56.12kJ·mol-1。
關(guān)鍵字: HDS失活催化劑; 焙燒; 釩; 動力學(xué)
(School of Materials and Metallurgy, Northeastern University, Shengyang 110006, China)
Abstract:Vanadium can be recovered from spent HDS catalyst by roasting it with air in a fixed bed reactor and then immersing roast product with sodium carbonate solution. The relationship between vanadium recovery and catalyst diameter, roasting temperature and roasting time is investigated. The experiment results indicate that the roasting reaction kinetics can be expressed by the shrinking core model. When catalyst particle diameter is <60μm, the roasting process is judged as reaction controlled step . At the conditions of diameter >60μm,high roasting temperature and large vanadium recovery, the process rate is controlled by reaction and inner-diffusion simultaneously. The kinetics equations for two different controlled steps are found . The activation energy within 923~1123K is 56.12kJ·mol-1
Key words: HDS spent catalyst; roast; vanadium; reaction dynamics


