Contrasting effect of zirconium-, iron-, and zirconium/iron-modified attapulgites capping and amendment on phosphorus mobilization in sediment

Enhanced remediation of As(iii) and As(v) by new zirconium-loaded attapulgite and its mechanisms in the aquatic environment

“…This might be relevant to such a fact that Mg 2+ reacted with As to form neutral molecules to weaken the electrostatic repulsion between Zr-ATP and negatively charged arsenite and improve the adsorption efficiency. 73 The presence of Ca 2+ (50.00–200.00 mg L −1 ) had a significant ( p < 0.05) effect on the Zr-ATP adsorption to As( iii ) and As( v ). In addition, the removal rate increased from 89.6 to 93.0% for As( iii ), and from 97.4 to 98.6% for As( v ), which was consistent with other studies.…”

Phosphorus migration from sediment to phosphorus-inactivating material: A key process neglected by common phosphorus immobilization assessments for lake geoengineering

“…Lake geoengineering, which involves in situ P immobilization, in which P deposition in sediment is accelerated using P-inactivating materials, is a commonly considered method for pollution control ( Zeller and Zeller, 2021 ; Zhang et al., 2021 ; Lurling and Mucci, 2020 ). Various P-inactivating materials, especially those with a strong capability of immobilizing P in sediment, such as modified-bentonites ( Douglas, 2002 ; Zhan et al., 2023 ), attapulgites ( Liu et al., 2022 ), and zeolites ( Wu et al., 2022a ; Lin et al., 2019a ), have been developed. However, unexpected outcomes have been reported in a series of practical applications ( Immers et al., 2015 ; Dadi et al., 2023 ), raising concerns about the reliability of the immobilization method ( Spears et al., 2014 ).…”