1. Enhanced Pb immobilization via the combination of biochar and phosphate solubilizing bacteria.
- Author
-
Chen H, Zhang J, Tang L, Su M, Tian D, Zhang L, Li Z, and Hu S
- Subjects
- Adsorption, Charcoal chemistry, Metals, Heavy analysis, Oryza chemistry, Phosphates chemistry, Sewage, Soil chemistry, Bacteria metabolism, Charcoal metabolism, Environmental Restoration and Remediation methods, Lead chemistry, Phosphates metabolism, Soil Pollutants chemistry
- Abstract
Application of biochar in heavy metal remediation suffers from lack of long-term stability. Phosphate-solubilizing bacteria (PSB) are able to elevate P release and the subsequent reaction with Pb to form stable pyromorphite. This study investigated the feasibility of applying PSB modified biochar to enhance immobilization of Pb
2+ . An alkaline biochar produced from rice husk (RB) and a slightly acidic biochar produced from sludge (SB) were selected. It showed that the biochars can effectively remove Pb2+ via adsorption, i.e., aqueous Pb concentrations after RB and SB addition were reduced by 18.61 and 53.89% respectively. The addition of PSB increased the Pb2+ removal for both biochars (to 24.11 and 60.85%, respectively). In particular, PSB significantly enhanced the formation of stable pyromorphite on surface of SB. This is due to that the evenly distributed PSB enhanced P release and regulated pH on the biochar surface. Moreover, small particles (<0.074 mm) showed their higher ability to induce the formation of pyromorphite, for both RB and SB. Nevertheless, SB demonstrated higher capability of sorption, together with its more abundant P content, which provided a more suitable platform to attract PSB to immobilize heavy metals. Therefore, the combination of biochar and PSB is a promising candidate material for heavy metal remediation. However, the types and particle size distribution of biochar should be addressed., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2019
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