Making Pb Adsorption-Saturated Attapulgite with Excellent Photocatalysis Properties through a Vulcanization Reaction and Its Application for MB Wastewater Degradation

Int J Environ Res Public Health. 2022 Aug 22;19(16):10457. doi: 10.3390/ijerph191610457.

Abstract

Attapulgite (AT) is a clay mineral with rich reserves in China, and it has good adsorption activity for Pb-containing wastewater. However, as a hazardous waste, the treatment of Pb adsorption-saturated attapulgite was quite difficult. In this work, through a simple vulcanization reaction, the waste Pb adsorption-saturated attapulgite (AT@Pb) was transformed into composite materials (AT@PbS) with good photocatalytic performance. After comprehensive material characterization (including XRD, TEM, XPS, and UV-Vis), the photocatalytic degradation performance and mechanism of AT@PbS for methylene blue (MB) were investigated. The results revealed that AT@PbS was a composite material of attapulgite nanorods (500-600 nm) and nanosquare PbS particles (80-100 nm). Additionally, AT@PbS displayed good visible light absorption, improved photo-electric properties, excellent photodegradation performance for MB, and recycling stability. Moreover, the energy band range of AT@PbS was about -0.043 V to 1.367 V. The photo-generated holes and their derived hydroxyl radicals were the main active species for MB degradation. This work not only provides a new approach to construct the composite photocatalyst, but also demonstrates the possibility of the comprehensive utilization of heavy metal adsorbents for wastewater degradation.

Keywords: MB; PbS; adsorption-saturated; attapulgite; photocatalysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Magnesium Compounds
  • Methylene Blue*
  • Photolysis
  • Silicon Compounds
  • Wastewater*

Substances

  • Magnesium Compounds
  • Silicon Compounds
  • Waste Water
  • Methylene Blue
  • attapulgite

Grants and funding

This work is supported by the Zhenjiang City 2021 Key Research and Development Project (Social Development) under grant NO. SH2021020 (Zhenjiang Science and Technology Bureau, Zhenjiang, Jiangsu, China), 2021 Jiangsu Province University Students Innovation and Entrepreneurship Training Program Project under grant NO. 202114000015Y (Jiangsu Education Department, Jiangsu, China).