AI Article Synopsis

  • * A new composite material, CA/nZVI/RSBC, was developed to effectively remove Cr(VI) and Mn(II) from wastewater, showing better adsorption capacities than traditional biochar.
  • * The study found that the main mechanism for Cr(VI) removal was redox reactions, while Mn(II) removal was primarily due to electrostatic attraction, confirming the composite's effectiveness for simultaneous heavy metal removal.

Article Abstract

Heavy metal pollution in water caused by industrial activities has become a global environmental issue. Among them, manganese mining and smelting activities have caused the combined pollution of Cr(VI) and Mn(II) in water, posing a serious ecotoxicological risk to ecological environments and human health. To efficiently remove Cr(VI) and Mn(II) from wastewater, a novel biochar supported nanoscale zerovalent iron-calcium alginate composite (CA/nZVI/RSBC) was synthesized by liquid-phase reduction and calcium alginate embedding methods. The adsorption performance and mechanisms of Cr(VI) and Mn(II) by CA/nZVI/RSBC were investigated. The maximum adsorption capacities of Cr(VI) and Mn(II) onto CA/nZVI/RSBC fitted by the Langmuir model were 5.38 and 39.78 mg/g, respectively, which were much higher than the pristine biochar. The iron release from CA/nZVI/RSBC was comparatively lower than that of nZVI/RSBC. Mn(II) presence enhanced the reduction of Cr(VI) by CA/nZVI/RSBC. The results of XRD, XPS, and site energy distribution analysis indicated that redox was the predominant mechanism of Cr(VI) adsorption, while electrostatic attraction dominated Mn(II) adsorption. This study provides a novel alternative way for the simultaneous removal of Cr(VI) and Mn(II) in wastewater.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envpol.2023.123148DOI Listing

Publication Analysis

Top Keywords

crvi mnii
20
biochar supported
8
supported nanoscale
8
nanoscale zerovalent
8
zerovalent iron-calcium
8
iron-calcium alginate
8
alginate composite
8
simultaneous removal
8
mnii
8
crvi
8

Similar Publications

Heavy metal contamination is an increasing global threat to human and environmental health, particularly in resource-limited areas. Traditional platforms for heavy metal detection are labor intensive and expensive and require lab facilities. While paper-based colorimetric sensors offer a simpler approach, their sensitivity limitations prevent them from meeting legislative requirements for many metals.

View Article and Find Full Text PDF

Enhancing Photoreduction of Cr(VI) through a Multivalent Manganese(II)-Organic Framework Incorporating Anthracene Moieties.

Inorg Chem

September 2024

Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.

Article Synopsis
  • * The anthracene group acts as a photosensitizer while the Mn(II) ion functions as the photocatalyst, enabling the conversion of Cr(VI) to Cr(III) within just 40 minutes.
  • * The new photocatalyst shows a much higher reaction rate compared to previous 3D MOFs, likely due to improved electron transfer and separation of photogenerated electrons under acidic conditions (p
View Article and Find Full Text PDF

Bromate-induced oxidation of carbamazepine and toxicity assessment of transformation products in the freezing-sunlight process: Effects of trivalent chromium.

Environ Res

December 2024

Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun 130012, China. Electronic address:

Article Synopsis
  • Bromate (BrO) can oxidize pharmaceuticals and personal care products (PPCPs) more effectively in freezing conditions, but the role of certain metals, like Cr(III), in this process is often ignored.
  • When Cr(III) is present, it significantly reduces the effectiveness of BrO in breaking down the PPCP carbamazepine (CBZ) in ice, with degradation rates dropping by up to 60.3%.
  • Instead of degrading CBZ, Cr(III) reacts with oxidants to produce Cr(VI), which alters the degradation dynamics in the presence of sunlight, leading to a complex interplay of factors affecting PPCP toxicity in frozen environments.*
View Article and Find Full Text PDF

Schwertmannite (Sch) is considered as an effective remover of Chromium (Cr) due to its strong affinity for toxic Cr species. Since the instability of Sch, the environmental fate of Cr deserves attention during the transformation of Sch into a more stable crystalline phase. The ubiquitous manganese(II) (Mn(II)) probably affects the transformation of Sch and thus the environmental fate of Cr.

View Article and Find Full Text PDF

Re-yellowing of chromium-contaminated soil after reduction-based remediation: Effects and mechanisms of extreme natural conditions.

Sci Total Environ

May 2024

Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China. Electronic address:

Chromium (VI) in soil poses a significant threat to the environment and human health. Despite efforts to remediate Cr contaminated soil (Cr-soil), instances of re-yellowing have been observed over time. To understand the causes of re-yellowing as well as the influence of overdosed chemical reductant in remediating Cr-soil, experiments on excess reducing agent interference and soil re-yellowing mechanisms under different extreme conditions were conducted.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!