摘要
利用EXAFS、XANES和XRD方法对负载三氯化铁的煤半焦中铁化学形态进行了表征,并着重考察煤的性质和铁负载量对铁化学形态的影响。在600℃热解条件下,两种褐煤载铁半焦中铁主要以晶相Fe_3O_4存在,而烟煤载铁半焦中以Fe_3O_4、FeO和α-Fe混合物相存在。这可能源于烟煤中存在较少的含氧官能团和较多的固定碳。对于富含有机硫的煤,负载铁与其中有机硫化合物发生作用并在给定热解条件下形成Fe_(1-x)S。铁负载量在研究范围内对铁化学形态的影响较小。
EXAFS,XANES and XRD methods were used tO Characterize the iron species formed during pyrolysis of FeCl_3-loaded coals,paying a special attention to effects of coal properties and iron loading on the iron chemical forms. Under 600 ℃ pyrolysis condition,crystalline Fe_3O_4 is main form in two types of brown coal semichars, but a mixed phase consisting of Fe_3O-4,FeO and a fraction of a-Fe was observed in a bituminous coal semichar.It seems that there are less oxygen-containing functional groups and much more fixed carbons in bituminous coal than in brown coal.For the coal with high organic sulfur,there is a strong interaction between the loaded iron and the organic sulfur compounds,and Fe_(1-x)S formed under the pyrolysis condition.In the range of this studied,iron loading has a small effection on the iron chemical forms.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1996年第2期125-130,共6页
Journal of Fuel Chemistry and Technology