title: Immobilization of Mn and NH4 (+)-N from electrolytic manganese residue waste.
abstract: The objective of this work was the immobilization of soluble manganese (Mn) and ammonium nitrogen (NH4 (+)-N) leached from electrolytic manganese residue (EMR). Immobilization of Mn was investigated via carbonation using carbon dioxide (CO2) and alkaline additives. NH4 (+)-N immobilization was evaluated via struvite precipitation using magnesium and phosphate sources. Results indicated that the immobilization efficiency of Mn using CO2 and quicklime (CaO) was higher than using CO2 and sodium hydroxide (NaOH). This higher efficiency was likely due to the slower release of OH(-) during CaO hydrolysis. The immobilization efficiency of Mn was >99.99 % at the CaO:EMR mass ratio of 0.05:1 for 20-min reaction time. The struvite precipitation of NH4 (+)-N was conducted in the carbonated EMR slurry and the immobilization efficiency was 89 % using MgCl2 · 6H2O + Na3PO4 · 12H2O at the Mg:P:N molar ratio of 1.5:1.5:1 for 90-min reaction time. A leaching test showed that the concentrations of Mn and NH4 (+)-N in the filtrate of the treated EMR were 0.2 and 9 mg/L, respectively. The combined immobilization of Mn and NH4 (+)-N was an effective pretreatment method in the harmless treatment of the EMR.
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.|College of Chemistry and Chemical Engineering, Anshun University, Anshun, 561000, People's Republic of China.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Chen
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, People's Republic of China. lrlcqu@163.com.
authors.forename: Renlong
authors.initials: R
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.
authors.forename: Zuohua
authors.initials: Z
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Shu
authors.affiliation: College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.
authors.forename: Changyuan
authors.initials: C
authors.lastname: Tao
mesh_terms: D064751:Ammonium Compounds / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry; D004572:Electrolysis; D004573:Electrolytes; D008274:Magnesium / Q000737:chemistry; D008345:Manganese / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D000069877:Struvite / Q000737:chemistry
chemical_list: D064751:Ammonium Compounds; D017610:Calcium Compounds; D004573:Electrolytes; D010087:Oxides; D010710:Phosphates; D008345:Manganese; D000069877:Struvite; C016538:lime; D008274:Magnesium; D009584:Nitrogen
keywords: Carbonation; Electrolytic manganese residue; Mn; NH4 +-N; Struvite precipitation