Mechanism analysis of its high defluoridation
Water fluoridation is the controlled adjustment of fluoride to public water supply to reduce tooth decay. Nonetheless, excessive fluoride in water can result in extreme toxicosis. To this end, the World Health Organization (WHO) has set a limit to the maximum quantity of fluoride that should be present in drinking water. However, it is rather unfortunate that the set standard poses a significant challenge to achieve in many areas of the world. As such, remediation of fluoride contamination is always a focus of public environmental safety and is urgently needed. Over the years, various techniques for removing excess fluoride from water have been developed; among which the adsorption method has been generally accepted credit to its low cost, high efficiency, and ease of operation, but still ought to be improved. Zirconium and aluminum are commonly used as effective adsorbent constituents for fluoride removal because of their high affinity towards F−. Ordinarily, these adsorbents are usually prepared by deposition from soluble sources of zirconium and/or aluminum. Recent publications have shown that the deposition conditions need to be carefully controlled.
Recent technological advents have yielded the Sonochemical syntheses methods. These methods can be used for the preparation of both inorganic and organic materials. In addition, these techniques have attracted increasing attention due to their convenience, green properties and are rapid and easily controlled. Taking this into consideration, researchers from the Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle in China: Qi Wang, Professor Pinghua Chen, Professor Hualin Jiang, Xueqin Li, Tao Wang, Dr. Guisheng Zeng, Dr. Lingling Liu and Professor Xubiao Luo, in collaboration with Xiong Zeng at the Nantong Runlin Chemicals Co., Ltd, China, Feifan Meng at the Lianyungang Rutai Environmental Material Co., Ltd China, and Professor Hongying Shu at the College of Environmental and Chemical Engineering, Nanchang Hangkong University developed a facile sonochemical method in the development of a nanocomposite of (ZrO2-Al2O3)/GO. Their work is currently published in Journal of Hazardous Materials.
Technically, the reaarch team used a sonochemical method to prepare nanocomposites which could quickly produce metal oxide nanoparticles directly from soluble Zirconium and Aluminum sources without using any precipitants. Overall, the researchers thoroughly investigated the structural properties and defluoridation performance of (ZrO2-Al2O3)/GO.
The authors reported that the as-synthesized (ZrO2-Al2O3)/GO exhibited a maximum fluoride adsorption capacity of 62.2 mg/g, and an adsorption ability of 13.80 mg/g when the F− equilibrium concentration was 1 mg/L, both of which were higher than most previously reported de-fluoridation adsorbents. Based on the experimental analysis, (ZrO2-Al2O3)/GO was reported to portray excellent adsorbent characteristics that were vital for de-fluoridation purposes.
In summary, the study demonstrated the successful synthesis of nanocomposites of (ZrO2-Al2O3)/GO by the sonochemical method. The study established that under ultrasonication treatment, nanoparticles of ZrO2 and Al2O3 (that exhibit exceptionally high de-fluoridation performance) could quickly form without using a precipitant. In a statement to Advances in Engineering, Professor Hualin Jiang further clarified that owing to the simple preparation, easy operation and high performance, the developed adsorbent and the related sonochemical method could be considered vital for developing highly effective adsorbents.
Qi Wang, Pinghua Chen, Xiong Zeng, Hualin Jiang, Feifan Meng, Xueqin Li, Tao Wang, Guisheng Zeng, Lingling Liu, Hongying Shu, Xubiao Luo. Synthesis of (ZrO2-Al2O3)/GO nanocomposite by sonochemical method and the mechanism analysis of its high defluoridation. Journal of Hazardous Materials, volume 381 (2020) page 120954..