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Boron removal from aqueous solution by direct contact membrane distillation
Deyin Hou1, Jun Wang, Xiangcheng Sun
1State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085, China.
Journal of Hazardous Materials
|January 19, 2010
Summary
Direct contact membrane distillation (DCMD) effectively removes over 99.8% of boron from water using polyvinylidene fluoride (PVDF) membranes. This efficient boron removal process meets stringent water quality standards even at high concentrations.
Area of Science:
- Environmental Science
- Chemical Engineering
- Materials Science
Background:
- Boron contamination in water poses health and environmental risks.
- Effective boron removal technologies are crucial for safe water supply.
- Membrane distillation offers a promising approach for water purification.
Purpose of the Study:
- To investigate the efficacy of direct contact membrane distillation (DCMD) for boron removal.
- To evaluate the performance of self-prepared polyvinylidene fluoride (PVDF) hollow fiber membranes in DCMD.
- To determine the impact of operational parameters on boron rejection efficiency.
Main Methods:
- Fabrication of PVDF hollow fiber membranes.
- Experimental setup for DCMD.
- Systematic variation of feed solution parameters: pH, boron concentration, temperature, and salt concentration.
- Analysis of permeate quality for boron concentration.
Main Results:
- DCMD achieved high boron removal efficiency (>99.8%).
- Boron rejection showed minimal dependence on feed pH and salt concentration.
- Permeate flux increased exponentially with feed temperature, but boron rejection remained unaffected.
- Treated groundwater with 12.7 mg/L boron yielded permeate boron below 20 µg/L.
- Pre-acidification improved permeate flux stability during groundwater treatment.
Conclusions:
- DCMD is a highly efficient method for removing boron from aqueous solutions.
- PVDF hollow fiber membranes are suitable for DCMD-based boron removal.
- The DCMD process is robust and effective across a range of operational conditions and water matrices.
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