Efficient immobilization of Cd2+ by nanoscale carbonate hydroxyapatite synthesized by ureolytic bacteria

As one of the five most toxic heavy metals, cadmium pollution seriously endangers human health and food safety. Carbonate hydroxyapatite has attracted our attention because of its excellent cleaning ability. However, few ecofriendly synthetic processes of nanoscale carbonate hydroxyapatite limit its application. In this study, we designed a medium that was used to prepare carbonate hydroxyapatite through microbial mineralization. The nano-flaky structure gives it a large specific surface area, which not only can achieve rapid adsorption of Cd2+ but also has a large adsorption capacity (270 mg/g). Dynamic adsorption experiments showed that adsorption is a spontaneous endothermic process. Ion exchange, surface complexation, and co-precipitation are the main adsorption mechanisms. This simple and readily available bio-carbonate hydroxyapatite provides potential candidates for heav y metal bioremediation in polluted environments. (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a medium was designed for the preparation of nano-scale carbonate hydroxyapatite through microbial mineralization, which has a large specific surface area and adsorption capacity, making it a potential candidate for heavy metal bioremediation in polluted environments.