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Composite Geological Materials for Treatment of Arsenic in Groundwater |
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| รหัสดีโอไอ | |
| Creator | Paveena Kitbutrawat |
| Title | Composite Geological Materials for Treatment of Arsenic in Groundwater |
| Contributor | Waruntorn Kanitpanyacharoen, Seelawut Damrongsiri |
| Publisher | Department of Geology, Chulalongkorn University |
| Publication Year | 2560 |
| Journal Title | Bulletin of Earth Sciences of Thailand (BEST) |
| Journal Vol. | 9 |
| Journal No. | 1 |
| Page no. | 24-35 |
| Keyword | Arsenic, Siltstone, Expanded perlite, Soil sample |
| URL Website | https://www.bestjournal.org/ |
| Website title | Bulletin of Earth Sciences of Thailand |
| ISSN | 1906-280X |
| Abstract | Arsenic contamination in groundwater is an important problem in many countries and responsible for many life-threatening diseases such as black fever, cancer, neurological and cardiovascular diseases. Despite the proposal of several remediation techniques, it has been challenging to find a cost-effective method to remove arsenic from groundwater in Thailand. This research is thus aimed to study chemical and physical properties of geological materials to create cost-effective adsorbents for arsenic removal. The most effective adsorbent in this study is made of porous siltstone, expanded perlite, and soil sample at the ratio of 66.67 to 16.67 to 16.67, respectively. The adsorbents are first tested with laboratory-based arsenic contaminated water at different conditions to identify the amount of adsorbent and adsorbate that can effectively remove arsenic and understand the underlying mechanisms of adsorption. Results show that the use of 10 grams of adsorbents per 50 ml of adsorbate at the pH of 7 with 2 hours of contact time can remove arsenic up to 41.39%. The value of 1/n from Freundlich adsorption isotherm is 1.27, indicating that the surface of adsorbent is heterogeneous. The energy of sorption from Dubinin Radushkevich adsorption isotherm is 3.79 kJ/mol, suggesting the kinetic is physical adsorption. In addition, the maximum capacity of adsorbent from Langmuir adsorption isotherm is 0.45 mg/g. Adsorbents are further tested with natural groundwater from 11 wells in Amphoe Dan Chang, Suphan Buri and Amphoe Ban Rai, Uthai Thani, which contain arsenic ranges from 16.13 to 362.3 ตg/l and have pH ranges from 6.95 to 7.35. Arsenic can be effectively removed between 20.17% and 75.31%. The variable amount of arsenic removal is likely due to the presence of phosphate, which has a similar structure to arsenite. In addition, the disintegration of adsorbents may release a noticeable amount of magnesium, which in turn inhibits the adsorption of arsenic and decreases the arsenic removal percentage. |
