Nano-Scale Drinking Water Treatment Residuals Affect Arsenic Fractionation and Speciation in Biosolids-Amended Agricultural Soil

Abstract

An incubation experiment was conducted to determine the effects of nanoscale drinking water treatment residuals (nWTRs) on arsenic (As) fractionation and speciation in agricultural soil amended with biosolids. The soils were treated with biosolids of 3% (w/w), along with nWTR application rates of 0, 0.25, 0.50, or 1.00% (w/w). The results revealed that the As adsorption rate increased with increasing the As treatment level from 50 to 800 mg/L. The maximum efficiency of As adsorption was 95%–98% in the soil treated with nWTRs of 1%, while the least As adsorption was 53%–91% in the soil treated with nWTRs of 0.25%. The overall As bioavailability in the biosolids-amended soil followed a descending order of nWTRs treatment: (0%) > 0.25% nWTRs, >0.50% nWTRs, and >1% nWTRs. The addition of nWTRs significantly changed As speciation in biosolids-amended soil. The X-ray absorption near-edge structure spectroscopy (XANES) and MINEQL+4.6 analyses showed that most of As was in a oxidized form of As5+ that likely incorporated in As pentoxide, and thus, with low mobility, bioavailability, and toxicity. This study demonstrated that nWTRs were effective in adsorbing and immobilizing As in biosolids-amended agricultural soils by forming stable As-nWTR surface complexes.

Enhancing Maize Yield and Soil Health through the Residual Impact of Nanomaterials in Contaminated Soils to Sustain Food

“…The addition of nB and nWTR at varying rates in degraded soil resulted in a considerable increase in microbial biomass carbon (MBC), as well as the activities of dehydrogenase (DHA) and catalase (CLA) and the canola production in treated pots [ 7 ]. According to Mahdy et al [ 10 ], stable As-nWTR surface complexes were formed by nWTRs, which effectively immobilized and adsorb arsenic (As) in agricultural soils modified with biosolids. According to earlier studies [ 1 , 11 ], nWTR can be used as a soil amendment to regulate P mobility and adsorption in salt-affected soils as well as in some heavy metals and dyes.…”

Nano‐water treatment residuals: Enhancing phosphorus kinetics and optimization in saline soils

“…Nanoparticles have been largely used for the remediation of environmental problems due to the active surface area of nanomaterials that dramatically increase their adsorption capacity compared to bulk materials (Caporale et al, 2013; Mahdy et al, 2020; Sebastian et al, 2018). Previous studies have shown conclusively that the teeny fractions of WTR significantly enhanced its active surface area and boosted its adsorption capacity (Caporale et al, 2013; Elkhatib et al, 2015; Mahmoud et al, 2020).…”