title: Water treatment residual (WTR)-coated wood mulch for alleviation of toxic metals and phosphorus from polluted urban stormwater runoff.
abstract: Aluminum-based water treatment residual (WTR)-coated wood mulches were synthesized and tested for removal of heavy metals and phosphorus (P) in synthetic urban stormwater. WTRs are an industrial waste produced from coagulation in water treatment facilities, primarily composed of amorphous aluminum or iron hydroxides. Batch tests showed that the composite filter media could effectively adsorb 97% lead (Pb), 76% zinc (Zn), 81% copper (Cu) and 97% P from the synthetic stormwater (Pb = 100 μg/L, Zn = 800 μg/L, Cu = 100 μg/L, P = 2.30 mg/L, and pH = 7.0) within 120 min, due to the presence of aluminum hydroxides as an active adsorbent. The adsorption was a 2(nd)-order reaction with respect toward each pollutant. Column tests demonstrated that the WTR-coated mulches considerably alleviated the select pollutants under a continuous-flow condition over the entire filtration period. The effluent Pb, Zn, Cu, and P varied at 0.5-8.9%, 33.4-46.7%, 45.8-55.8%, and 6.4-51.9% of their respective initial concentrations with the increasing bed volume from 0 to 50. Synthetic precipitation leaching procedure (SPLP) and toxicity characteristic leaching procedure (TCLP) tests indicated that leached contaminants were all below the U.S. criteria, suggesting that the release of undesired chemicals under rainfall or landfilling conditions is not a concern during application. This study demonstrates that the WTR-coated mulches are a new, low-cost, and effective filter media for urban stormwater treatment. Equally important, this study provides a sustainable approach to beneficially reuse an industrial waste for environmental pollution control.
authors.affiliation: Department of Earth and Environmental Studies, Montclair State University, CELS 220, 1 Normal Ave, Montclair, NJ 07042, United States.
authors.forename: Hanieh
authors.initials: H
authors.lastname: Soleimanifar
authors.affiliation: Department of Earth and Environmental Studies, Montclair State University, CELS 220, 1 Normal Ave, Montclair, NJ 07042, United States. Electronic address: dengy@mail.montclair.edu.
authors.forename: Yang
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Microscopy and Microanalysis Research Laboratory, Montclair State University, CELS 100B, 1 Normal Ave, Montclair, NJ 07042, United States.
authors.forename: Laying
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, United States.
authors.forename: Dibyendu
authors.initials: D
authors.lastname: Sarkar
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000032:analysis / Q000737:chemistry; D003300:Copper / Q000032:analysis / Q000737:chemistry; D005290:Ferric Compounds / Q000032:analysis / Q000737:chemistry; D005374:Filtration / Q000379:methods*; D000075322:Heavy Metal Poisoning; D007220:Industrial Waste / Q000032:analysis*; D007854:Lead / Q000032:analysis / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry*; D011041:Poisoning; D014876:Water Pollution / Q000032:analysis*; D018508:Water Purification / Q000379:methods*; D014934:Wood / Q000737:chemistry*; D015032:Zinc / Q000032:analysis / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D007220:Industrial Waste; D019216:Metals, Heavy; D010758:Phosphorus; D007854:Lead; C021024:ferric hydroxide; D003300:Copper; D000535:Aluminum; D015032:Zinc
keywords: Adsorption; Phosphorus; Toxic metals; Urban stormwater pollutants; Water treatment residuals; Wood mulch