Granulation and ferric oxides loading enable biochar derived from cotton stalk to remove phosphate from water

• Published in: Bioresource technology Vol. 178; pp. 119 - 125
• Main Authors: Ren, Jing, Li, Nan, Li, Lei, An, Jing-Kun, Zhao, Lin, Ren, Nan-Qi
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.02.2015
• Subjects: Adsorbents; Adsorption; Biochar; Biotechnology - methods; Charcoal - chemistry; Cotton; Ferric Compounds - chemistry; Ferric oxide; Ferric oxides; Gossypium - chemistry; Granulation; oxides; Phosphate removal; Phosphates; Phosphates - chemistry; Porosity; porous media; Powders; Soil; Surface area; Surface chemistry; Water - chemistry; Water Pollutants, Chemical - analysis; Water Purification; Ferric oxides; Phosphate removal; Granulation; Biochar
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2014.09.071

[Display omitted] •Granulation followed by ferric loading had the best phosphate adsorption capacity.•The phosphate adsorption capacity was increased from 0 to 0.963mg/g.•Both granulation and ferric oxides loading obviously increased the surface areas.•Pseudo-first order model is allowable to estimate the adsorption kinetics. Granulation of biochar powder followed by immobilization of ferric oxides on the macroporous granular biochar (Bg-FO-1) substantially enhanced phosphate removal from water. BET analysis confirmed that both granulation and ferric oxides loading can increase the surface areas and pore volumes effectively. Bg-FO-1 was proven to be a favorable adsorbent for phosphate. The phosphate adsorption capacity was substantially increased from 0mg/g of raw biochar powder to 0.963mg/g (Bg-FO-1). When the ferric oxides loading was prior to granulation, the adsorption capacity was decreased by 59–0.399mg/g, possibly due to the decrease of micropore and mesopore area as well as the overlaying of binders to the activated sites produced by ferric oxides.