鲤鱼肉骨生物炭的制备及其吸附水中Pb2+特性

Preparation of Carp Meat Bone Biochar and Its Adsorption Characteristics for Pb2+ from Water

以水产养殖固体废弃物病死鲤鱼为生物质原材料,采用限氧裂解技术在600℃条件下制备鲤鱼肉骨生物炭(CMBB),探究了CMBB对水中Pb^2+的吸附特性,并对CMBB的结构和性质进行了表征。结果表明,CMBB表面具有不规则的中孔和微孔结构,表面带有大量的负电荷。CMBB对Pb^2+的吸附在4 h内达到平衡,动力学过程符合准2级动力学模型;吸附速率受内扩散机制控制,但并非唯一的控制机制;Pb^2+在CMBB上的等温吸附过程符合Langmuir、Langmuir-Freundlich和Temkin等温吸附模型,属于有利吸附;吸附过程为自发进行的熵增吸热过程。CMBB能够在较宽的pH范围(2~6)对Pb^2+具有明显的去除效果(去除率大于99%)。

The carp meat bone biochar(CMBB) was prepared by limited oxygen cracking technology at 600 ℃, the aquaculture solid waste(dead carp)as the raw material, the adsorption characteristics of CMBB for Pb^2+in aqueous solutions was studied, and the structure and property of CMBB was characterized. The results showed that the surface of CMBB had irregular mesopores and microporous structure, and had a large amount of negative charge.The adsorption of Pb^2+onto CMBB could reach equilibrium after 4 h of reaction. The adsorption kinetics followed the pseudo-second-order kinetcs. The adsorption rate was controlled by internal diffusion mechanism and it was not the only control mechanism. The isotherm adsorption process of Pb^2+onto CMBB was fitted well with the Langmuir, Langmuir-Freundlich and Temkin model, and belonged to beneficial adsorption. The adsorption process was spontaneous, entropy increase and endothermic process. CMBB had a good removal rate(>99%) for Pb^2+in a wide pH range(2~6).