title: Manganese oxide-modified biochars: preparation, characterization, and sorption of arsenate and lead.
abstract: This work explored two modification methods to improve biochar's ability to sorb arsenic (As) and lead (Pb). In one, pine wood feedstock was pyrolyzed in the presence of MnCl2·4H2O (MPB) and in the other it was impregnated with birnessite via precipitation following pyrolysis (BPB). The resulting biochars were characterized using thermogravimetry, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and energy-dispersive X-ray analyses. The dominant crystalline forms of Mn oxides in the MPB and BPB were manganosite and birnessite, respectively. Batch sorption studies were carried out to determine the kinetics and magnitude of As(V) and Pb(II) onto the biochars. As(V) and Pb(II) sorption capacities of MPB (0.59 and 4.91 g/kg) and BPB (0.91 and 47.05 g/kg) were significantly higher than that of the unmodified biochar (0.20 and 2.35 g/kg). BPB showed the highest sorption enhancement because of the strong As(V) and Pb(II) affinity of its birnessite particles.
authors.affiliation: Tropical Research and Education Center, University of Florida, Homestead, FL 33031, United States; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Shengsen
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611, United States. Electronic address: bg55@ufl.edu.
authors.forename: Bin
authors.initials: B
authors.lastname: Gao
authors.affiliation: Tropical Research and Education Center, University of Florida, Homestead, FL 33031, United States; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Yuncong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Soils Department, Faculty of Agriculture, Mansoura University, 35516 Mansoura, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Mosa
authors.affiliation: Department of Geological Sciences, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Zimmerman
authors.affiliation: Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
authors.affiliation: Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Willie G
authors.initials: WG
authors.lastname: Harris
authors.affiliation: Tropical Research and Education Center, University of Florida, Homestead, FL 33031, United States; Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Kati W
authors.initials: KW
authors.lastname: Migliaccio
mesh_terms: D000327:Adsorption; D001149:Arsenates / Q000302:isolation & purification*; D002606:Charcoal / Q000737:chemistry*; D007700:Kinetics; D007854:Lead / Q000302:isolation & purification*; D017895:Manganese Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D028223:Pinus / Q000737:chemistry; D016062:Porosity; D013696:Temperature; D013818:Thermogravimetry; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D001149:Arsenates; D017895:Manganese Compounds; D010087:Oxides; D014874:Water Pollutants, Chemical; C540010:biochar; D002606:Charcoal; D007854:Lead; C027424:manganese oxide; C025657:arsenic acid
keywords: Adsorption; Biochar; Birnessite; MnO; Nanocomposite