化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2014年
8期
3136-3143
,共8页
覃吴%李渠%董长青%程伟良%杨勇平
覃吳%李渠%董長青%程偉良%楊勇平
담오%리거%동장청%정위량%양용평
吸附%二氧化碳%一氧化碳%化学链燃烧%反应动力学
吸附%二氧化碳%一氧化碳%化學鏈燃燒%反應動力學
흡부%이양화탄%일양화탄%화학련연소%반응동역학
adsorption%carbon dioxide%carbon monoxide%chemical-looping combustion%reaction dynamics
制备了不同量级Co掺杂Fe2O3载氧体Co-Fe2O3,利用BET和TEM对载氧体结构进行表征。通过在不同温度下Co-Fe2O3与气体燃料CO的还原反应,考察Co-Fe2O3对CO化学链燃烧特性。结果表明,同一温度条件下,掺杂量越高,还原反应转化率越高;掺杂量不变的情况下,温度升高促使还原程度加深,缩短了载氧体完全还原转化的时间。根据TGA曲线进行了化学动力学分析,发现Co0.2Fe还原反应过程在344.7~391.0℃和414.7~472.5℃温度范围反应动力学对应扩散控制的 Jander 方程模型,607.6~681.5℃温度范围对应二维扩散反应模型,并分别计算出相应模型的表观活化能和频率因子。结果可为化学链燃烧技术应用提供理论指导。
製備瞭不同量級Co摻雜Fe2O3載氧體Co-Fe2O3,利用BET和TEM對載氧體結構進行錶徵。通過在不同溫度下Co-Fe2O3與氣體燃料CO的還原反應,攷察Co-Fe2O3對CO化學鏈燃燒特性。結果錶明,同一溫度條件下,摻雜量越高,還原反應轉化率越高;摻雜量不變的情況下,溫度升高促使還原程度加深,縮短瞭載氧體完全還原轉化的時間。根據TGA麯線進行瞭化學動力學分析,髮現Co0.2Fe還原反應過程在344.7~391.0℃和414.7~472.5℃溫度範圍反應動力學對應擴散控製的 Jander 方程模型,607.6~681.5℃溫度範圍對應二維擴散反應模型,併分彆計算齣相應模型的錶觀活化能和頻率因子。結果可為化學鏈燃燒技術應用提供理論指導。
제비료불동량급Co참잡Fe2O3재양체Co-Fe2O3,이용BET화TEM대재양체결구진행표정。통과재불동온도하Co-Fe2O3여기체연료CO적환원반응,고찰Co-Fe2O3대CO화학련연소특성。결과표명,동일온도조건하,참잡량월고,환원반응전화솔월고;참잡량불변적정황하,온도승고촉사환원정도가심,축단료재양체완전환원전화적시간。근거TGA곡선진행료화학동역학분석,발현Co0.2Fe환원반응과정재344.7~391.0℃화414.7~472.5℃온도범위반응동역학대응확산공제적 Jander 방정모형,607.6~681.5℃온도범위대응이유확산반응모형,병분별계산출상응모형적표관활화능화빈솔인자。결과가위화학련연소기술응용제공이론지도。
Co-doped Fe2O3 of different orders of magnitude were prepared as oxygen carriers, the structures of which were characterized with adsorption-desorption (BET) and transmission electron microscope (TEM). Experiments under different temperatures were performed to investigate the reaction between Co-doped Fe2O3 and CO to understand the chemical looping combustion characteristics of these prepared oxygen carriers. The higher the doping amount, the higher the reduction conversion at the same temperature. However, with the same doping amount, increase of temperature led to increase of reduction degree, shortening the time of complete conversion of oxygen carrier. Further analysis of chemical kinetics and reaction dynamics based on TGA curve showed that the Jander equation model was suitable for the reduction of Co-doped Fe2O3 at 344.7-391.0℃ and 414.7-472.5℃, and the Valensi equation model was suitable for the reduction at 607.6-681.5℃, according to which the kinetic parameters including activation energy and pre-exponential factor were also calculated. The research results could provide theoretical guidance for further application of CLC technology.