化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2014年
8期
2988-2996
,共9页
煤化工%固定床%催化剂%天然气%反应动力学
煤化工%固定床%催化劑%天然氣%反應動力學
매화공%고정상%최화제%천연기%반응동역학
coal chemical industry%fixed bed%catalyst%natural gas%reaction kinetics
在固定床反应器中,以水蒸气为气化介质,考察了“一步法”煤制天然气K-Fe甲烷化催化剂的催化活性及稳定性,研究了反应动力学,并且考察了不同煤种对煤催化甲烷化的影响。在650℃、2 MPa下,K15Fe10Ca5对于煤气化及甲烷化均具有良好催化活性。XRD分析表明,活性组分K与Fe之间相互作用,形成的K6Fe2O5促进了煤气化及甲烷化反应。Ca助剂的引入抑制了活性组分与煤中矿物质的结合,同时吸收了煤焦释放出的含硫气体,提高了催化剂的活性。在5次循环实验过程中,CH4产率保持稳定,表明催化剂有较高的稳定性。修正随机孔模型很好地描述了K15Fe10Ca5催化神木煤焦甲烷化的行为,其中界面反应为控制步骤。煤中挥发分、灰分及含硫量等因素都会影响最终的产率。
在固定床反應器中,以水蒸氣為氣化介質,攷察瞭“一步法”煤製天然氣K-Fe甲烷化催化劑的催化活性及穩定性,研究瞭反應動力學,併且攷察瞭不同煤種對煤催化甲烷化的影響。在650℃、2 MPa下,K15Fe10Ca5對于煤氣化及甲烷化均具有良好催化活性。XRD分析錶明,活性組分K與Fe之間相互作用,形成的K6Fe2O5促進瞭煤氣化及甲烷化反應。Ca助劑的引入抑製瞭活性組分與煤中礦物質的結閤,同時吸收瞭煤焦釋放齣的含硫氣體,提高瞭催化劑的活性。在5次循環實驗過程中,CH4產率保持穩定,錶明催化劑有較高的穩定性。脩正隨機孔模型很好地描述瞭K15Fe10Ca5催化神木煤焦甲烷化的行為,其中界麵反應為控製步驟。煤中揮髮分、灰分及含硫量等因素都會影響最終的產率。
재고정상반응기중,이수증기위기화개질,고찰료“일보법”매제천연기K-Fe갑완화최화제적최화활성급은정성,연구료반응동역학,병차고찰료불동매충대매최화갑완화적영향。재650℃、2 MPa하,K15Fe10Ca5대우매기화급갑완화균구유량호최화활성。XRD분석표명,활성조분K여Fe지간상호작용,형성적K6Fe2O5촉진료매기화급갑완화반응。Ca조제적인입억제료활성조분여매중광물질적결합,동시흡수료매초석방출적함류기체,제고료최화제적활성。재5차순배실험과정중,CH4산솔보지은정,표명최화제유교고적은정성。수정수궤공모형흔호지묘술료K15Fe10Ca5최화신목매초갑완화적행위,기중계면반응위공제보취。매중휘발분、회분급함류량등인소도회영향최종적산솔。
An investigation into catalyst was conducted for one-step production of synthetic natural gas from coal in a fixed bed reactor using steam as gasification medium. The reactivity and stability of K-Fe catalyst in multi-cycles, as well as the kinetics model of methanation process and the effect of different coals on methanation, were studied. K15Fe10Ca5 catalyst showed significantly better activity in the coal gasification and methanation reactions at 650℃ and 2 MPa. Furthermore, X-ray diffraction data indicated that some highly active materials, such as K6Fe2O5 were formed by interaction of active components and enhanced reactivity. With the addition of calcium promoter, combination of active components and minerals in coal was prevented and the sulfur in coal could be fixed effectively. In multi-cycle experiments, CH4 yield remained stable. The methanation mechanism of Shenmu-coal with K15Fe10Ca5 could be described by the modified random pore model proposed, suggesting that interfacial reaction was the control step. The final yield was affected by volatile matter, ash content, and sulfur content.