Effects of bacterial inoculation and calcium source on microbial-induced carbonate precipitation for lead remediation

Effects of the Urease Concentration and Calcium Source on Enzyme-Induced Carbonate Precipitation for Lead Remediation

“…Here, urea hydrolysis was modeled as the initial condition about NH 4 + and CO 3 2− with a stoichiometric ratio of 2:1 ( Gat et al, 2017 ). The simulation for the evolution of the precipitation speciation was determined by the degrees of urea hydrolysis that require the inputs of NH 4 + and CO 3 2− concentrations toward differentiating the abiotic precipitation from the biotic precipitation that directly plays roles in urea hydrolysis ( Xue et al, 2022 ).…”

“…Such heavy metal contamination remediation by the traditional soil flushing measure is deemed time-consuming and costly since heavy metal ions are easily adsorbed by soil particles, and intensive industrial activities further aggravate heavy metal contamination ( Yang et al, 2014 ; An et al, 2019 ; Kumar and Dwivedi, 2019 ; Bai et al, 2021 ; Cheng et al, 2021 ; Duan et al, 2021 ; Wei et al, 2021 ; Yuan et al, 2021 ; Chen et al, 2022b ). In the past few years, various remediation measures, including but not limited to physical, chemical, and biological measures, have been proposed to deal with heavy-metal contamination ( Dhami et al, 2013 ; Shashank et al, 2016 ; Qian et al, 2017 ; Rahman et al, 2020 ; Ahenkorah et al, 2021a ; Hu et al, 2021 ; Jiang et al, 2021 ; and Xue et al, 2022 ). Amongst the heavy metal contamination remediation measures, enzyme-induced carbonate precipitation (EICP) is an environmentally friendly, efficient, and sustainable measure.…”

The Effect of Calcium Source on Pb and Cu Remediation Using Enzyme-Induced Carbonate Precipitation

“…In the past few decades, remediation methods including replacement, soil flushing, electrokinetic remediation, chemical precipitation, ion exchange, and phytoremediation were developed (Mena et al, 2016;Kumari et al, 2017;Kumari et al, 2018;Chen and Achal, 2019;Duarte-Nass et al, 2020;Ahenkorah et al, 2021;Hu L. et al, 2021;Jiang et al, 2021). However, they are usually time-consuming and may cause secondary pollution (Achal et al, 2012;Nancharaiah et al, 2016;Kappaun et al, 2018;Xue et al, 2022;Yan et al, 2021;Duan et al, 2021a;Cheng et al, 2021;Duan et al, 2021b). Furthermore, heavy metal ions may be re-released into surrounding environments when subjected to the change in environmental conditions (Hu et al, 2021b;Bai et al, 2017;Bai et al, 2021;Xue et al, 2021).…”

Effects of Bacterial Culture and Calcium Source Addition on Lead and Copper Remediation Using Bioinspired Calcium Carbonate Precipitation

“…Lead (Pb) and copper (Cu), that are featured with characters of toxicity, non-biodegradability, and bioaccumulation, are considered two common and dangerous heavy metal contaminants present in surrounding environments, which cause serious threats to plant and human health ( Zhao et al, 2016 ; Jiang et al, 2019 ; Liao et al, 2020 ). The mobility or solubility of heavy metals can transform them from the solid phase to the solution phase, thereby increasing their bioavailability ( Bolan et al, 2014 ; Bai et al, 2020 , Bai et al, 2021c ; Yang et al, 2021 ; Xue et al, 2022 ). Therefore, immobilizing heavy metals is considered to be of great necessity in order to reduce their bioavailability ( Li et al, 2013 ; Khadim et al, 2019 ; Cheng et al, 2021 ; Hu et al, 2021 ; Hu et al, 2022 ; Wang et al, 2022; Wang et al, 2022 ; Wang et al, 2022 ).…”

“…A ratio of the removed heavy metal concentration to the initial concentration has been defined as remediation efficiency, and it may vary with the degree of urea hydrolysis, pH surrounding conditions, and concentration of heavy metal ions ( Achal et al, 2012 ; Xue et al, 2022 ). As reported by Duarte-Nass et al (2020) , the remediation efficiency against copper degrades with the decrease in the degree of urea hydrolysis, and the degradation becomes more pronounced when subjected to higher heavy metal concentrations.…”