活性碳纤维对甲醛吸附转化性能的研究

用对胺基苯甲酸(PABA)浸渍粘胶基活性碳纤维(Rayon-ACF)和聚丙烯腈基活性碳纤维(PAN-ACF),考察了两者对甲醛吸附性能的差异。结果表明:PAN-ACF和Rayon-ACF经PABA溶液浸渍处理后,样品中的N含量都明显提高,但其比表面积、微孔容积和总孔容都有所下降;不过对甲醛溶液蒸汽的吸附容量都明显提高。这主要是归因于浸渍处理后样品中-NH2的增加,进而由于化学吸附而使得对甲醛吸附量增加。Rayon-ACF样品的甲醛吸附容量远高于PAN-ACF样品,这可能同Ray-on-ACF样品有较多表面含氧官能团以及较大的微孔容积有关。甲醛在ACF的微孔空间中易于形成高凝缩的三聚甲醛,从而其吸附容量相应提高。

Formaldehyde Removal by Activated Carbon Fiber

The difference for removal formaldehyde between Polyacrylonitrile (PAN) based and Rayon-based activated carbon fibers (ACF) impregnated by p-aminobenzoic acid (PABA) were investigated. It showed that PABA was hydrophilic and contains -NH2, which could react with -COOH of formaldehyde. After impregnating by PABA, N content of the treated ACFs increased, but their specific surface area, micropore volume and total pore volume decreased. The removal capacity for vapor from formaldehyde solution of treated ACFs was improved dramatically which was mainly due to the increasing of -NH2 and hence chemical adsorption occurred between the treated ACF and formaldehy de. The adsorption capacity for formaldehyde by Rayon-ACF was much higher than that by PAN-ACF may be because of much more active surface oxygen functional groups and relatively larger micropore volume in Rayon-ACF. Formaldehyde could easily form formaldehyde molecular clusters-paraformaldehyde in the micropore space of ACF, which led to the improvement for the adsorption of formaldehyde.