Plant-derived urease-induced calcium carbonate precipitation for solidifying limestone dust: Preparation, performance, and mechanism
Dust pollution from open-pit limestone mines poses a significant challenge to ecological systems and human health, hindering the advancement of green mining and sustainable practices. In contrast to conventional dust-suppression techniques-such as water spraying and the use of chemical or microbial suppressants-enzyme-induced carbonate precipitation (EICP) technology leverages plant-derived urease to produce biological dust suppressants, reducing potential environmental harm. This study evaluates the solidification performance of biological dust suppressants prepared with different calcium sources-calcium chloride (CaCl<sub>2</sub>), calcium nitrate (Ca(NO<sub>3</sub>)<sub>2</sub>), and calcium acetate (Ca(CH<sub>3</sub>COO)<sub>2</sub>)-through both macroscopic and microscopic analyses. The findings demonstrate significant advantages of EICP technology in terms of dust-suppression efficiency, environmental impact, and cost-effectiveness. All three biological dust suppressants maintain mildly alkaline pH values, with their calcium-source reactivity in aqueous solutions following the order: Ca(NO<sub>3</sub>)<sub>2</sub> > CaCl<sub>2</sub> > Ca(CH₃COO)₂. Each suppressant significantly promotes calcium carbonate (CaCO<sub>3</sub>) precipitation, with dust suppression efficiency ranked as follows: Ca(NO<sub>3</sub>)<sub>2</sub> > Ca(CH<sub>3</sub>COO)<sub>2</sub> > CaCl<sub>2</sub>. The Ca(NO<sub>3</sub>)<sub>2</sub>-based suppressant demonstrates maximum dust-suppression efficiencies of 94.28 % and 57.18 % at the lowest and highest wind speeds, respectively. The mineralized product mainly consists of uniformly distributed calcite-type CaCO₃, which improves structural stability by filling voids, bonding particles, and forming interconnections. Compared to traditional water and chemical suppressants, these biological dust suppressants offer cost reductions of 42.30-50.80 % and 3.30-12.40 %, respectively. Furthermore, the Ca(CH<sub>3</sub>COO)<sub>2</sub>-based suppressant exhibits the lowest corrosiveness, with a 96-h corrosion rate of 0.020 mm/a. Overall, this study highlights the economic viability, environmental compatibility, and sustainability of plant-derived urease-induced CaCO₃ precipitation technology as a promising approach to mitigating limestone dust pollution.
Authors
- Changbo Du (ORCID: https://orcid.org/0000-0002-3473-2600)
- Tao Han (ORCID: https://orcid.org/0000-0002-7396-1676)
- Huijie Huang
- Yuanfu Zhou (ORCID: https://orcid.org/0000-0002-0326-2351)
- Jianhui Deng (ORCID: https://orcid.org/0000-0003-0476-0253)
- Yi Fu (ORCID: https://orcid.org/0000-0001-6227-0020)
Institutions
- Liaoning Technical University (CN)
- Sichuan University (CN)
- State Key Laboratory of Hydraulics and Mountain River Engineering
- Chongqing Jiaotong University (CN)
Publication Details
- Journal
- International Journal of Biological Macromolecules
- Published
- 2025-04-04
- DOI
- https://doi.org/10.1016/j.ijbiomac.2025.142758
- Citations
- 1
- Primary Topic
- Microbial Applications in Construction Materials
- Type
- article
- Field-Weighted Citation Impact
- 0.80