Pyrolyzed fabrication of N/P co-doped biochars from (NH4)3PO4-pretreated coffee shells and appraisement for remedying aqueous Cr(VI) contaminants. (November 2020)

• Record Type: Journal Article
• Authors: Li, Jianqiu; He, Feifei; Shen, Xiaoyang; Hu, Dongwen; Huang, Qiang
• Is Part Of: Bioresource technology. Volume 315(2020)
• Publication Date: 2020-11
• Subjects: Agricultural residues -- Coffee shells -- Biochar -- Heteroatom doping -- Hexavalent chromium; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2020.123840
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Coffee shell-based biochars are prepared by an in-situ pyrolysis method. (NH4 )3 PO4 -pretreatment gives biochar large specific surface areas and sufficient N/P co-doping. The biochars exhibit high efficiencies in Cr(VI) removal and reduction. The role of N/P heteroatom groups is cleared. Abstract: In this study, an agricultural residue-derived biochar was fabricated by pyrolyzing coffee shells using (NH4 )3 PO4 pretreatment. The influence of pyrolysis temperature on the structure and properties of biochars was investigated. The elemental analysis, spectroscopic and textural studies showed that the biochars were endued sufficient N and P co-doping and large specific surface area by (NH4 )3 PO4 -pretreatment. The appraisement for remedying aqueous Cr(VI) contaminants demonstrated that the N/P co-doped biochars offered high efficiencies above 95% for aqueous Cr(VI) removal. The mechanism investigation displayed that the adsorption and reduction of Cr(VI) were boosted by the synergistic effect between the hierarchical pore structure and the groups related to oxygen, nitrogen and phosphorus. Moreover, the biochar can be readily regenerated by HCl solution soaking for reuses several times. This work should permit for providing a convenient utilization of coffee shell agricultural residues, and the coffee shell-derived biochars supplied potential for remedying Cr(VI) in effluents.