生物质和煤基活性炭制备过程的活化特性比较

Activation characteristics comparison of activated carbons prepared from biomass and lignite

分别以稻壳、木屑及褐煤为原料用水蒸气活化法制备了活性炭,比较了所得活性炭的吸附性能和炭化料的反应活性,探明了造成不同原料活化特性差异的原因。结果表明,活化过程中生物质原料的反应活性优于褐煤,炭化料的活化速率遵循脱灰稻壳>木材炭化料>稻壳炭化料>褐煤炭化料。通过对炭化料进行元素分析、气化反应活性分析、BET、SEM、XRD、FTIR、XPS等物理和化学性质的表征,揭示了不同原料表现出不同活化特性的原因。结果表明,在相同炭化和活化条件下,原料挥发分越高,灰分越低,炭化料有机含氧量越高,则水蒸气的活化速率越快,更容易在短时间内制备出高性能的活性炭。

This work compared the activation reactivities of different carbonized materials to justify the adsorption properties of the activated carbons prepared under the same steam activation conditions but from different raw materials,including rice husk,sawdust and lignite.The results showed that the activation reactivity of biomass feedstock was higher than lignite,and the activation rate of carbonized material varied in a descending order of ash-removed rice husk,sawdust,rice husk and lignite.Characterizing the carbonized materials by ultimate and proximate analysis,BET,SEM,XRD,FTIR,and XPS was performed to clarify further the reason for such different activation characteristics.It was found that the higher the volatile component and organic oxygen and the lower the ash content in the raw material,the easer it would be to produce high quality activated carbon via a short-time activation.