Effects of surface microstructure and chemical state of featherfiber-derived multidoped carbon fibers on the adsorption of organic water pollutants

Abstract

Cost-efficient synthesis of biomass-derived carbon-based adsorbents having high adsorption capacity for wastewater treatment has been reported. Multi-doped carbon fibers (MCFs) derived from pyrolysis of chicken featherfiber (CFF) have been investigated for their adsorption characteristics for organic water-pollutants. Effects of various structural parameters such as microstructure and surface chemical state of the MCFs on their adsorption properties have been investigated. The maximum adsorption capacity of ~170mg/g is observed for the MCF synthesized at the pyrolysis temperature of 600°C. Correlations between the adsorption capacities of the MCFs with their surface functionalities suggest the sp2 carbon to be the most active adsorption site. The Weber and Morris diffusion model suggests that surface adsorption and intraparticle diffusion play significant roles during MB adsorption on the MCFs. Further, the adsorption process follows Langmuir isotherms with a monolayer adsorption. Negative change in enthalpy with MB adsorption reveals the exothermic nature of the adsorption process. Furthermore, the MCFs exhibit high stability under aqueous solutions. This, combined with the adsorption studies using real-life wastewater samples, suggests the CFF derived MCFs to be the suitable adsorbents for large-scale wastewater treatment applications.