Recovery of phosphate with chemically modified biochars. Issue 1 (March 2016)

• Record Type: Journal Article
• Authors: Takaya, C.A.; Fletcher, L.A.; Singh, S.; Okwuosa, U.C.; Ross, A.B.
• Is Part Of: Journal of environmental chemical engineering. Volume 4:Issue 1(2016:Mar.)
• Page Start: 1156
• Page End: 1165
• Publication Date: 2016-03
• Subjects: Biochar modification -- Biomass pre-treatment -- Phosphate sorption; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2016.01.011
• Languages: English
• ISSNs: 2213-2929

Abstract

Highlights: Biochar phosphate adsorption can be enhanced from relatively low levels (e.g., 2.1–3.6%) to relatively high levels (66.4–70.3%) by impregnation with magnesium. Biomass pre-treatment with magnesium salts were markedly higher than those of biochar post-treatment. Biochar post-treatment with alkali also improved phosphate adsorption capacity but was not a function of biochar surface area. Abstract: The use of biochar for the recovery of phosphate has potential for environmental and socio-economic benefits but it is often characterised by relatively low nutrient adsorption capacity. The aim of this study was to investigate the potential for improving biochar phosphate adsorption capacities following chemical modification with metal salts, acids and alkali. Modified biochar were produced from oak wood and paprika waste (greenhouse waste) following either chemical treatment of biomass (in-situ modification) or biochar (post modification). Phosphate uptake capacities were determined by laboratory batch sorption tests, and results indicated that phosphate uptake could be enhanced from relatively low levels (2.1–3.6%) to relatively high levels (66.4–70.3%) by impregnation with magnesium. These findings suggest that biochar mineral composition is a key property influencing biochar phosphate uptake while surface area has less influence on sorption.