The use of Mg-Al Hydrotalcite for removing anionic contaminants such as Bromide, Sulphate, Nitrate, Fluoride and Chloride from aqueous solutions has been studied. The current study analyses the effect of calcination on the anionic removal efficiency of hydrotalcite. The hydrotalcite samples have been calcined batch-wise in a muffle furnace at different temperatures and are added to various anionic solutions in a conical flask and kept for stirring in a shaking incubator for three hours. The filtrate obtained is then analysed using Ion chromatography. The results obtained show a steady increase of anionic removal with an increase in calcination temperature. All anions under study show maximum removal towards calcinated samples than non-calcinated samples.For both calcinated and non- calcinated samples, it is found that the percentage removal of anions decreases with the increase of its ionic radii in the manner F^->Cl^->Br^->NO₃^->SO₄^2- which clearly states that calcination does not affect this behaviour and ionic radius is an influencing factor even without calcination.

中文翻译：

---

Mg-Al水滑石的合成，表征及煅烧对阴离子种类的去除作用研究

研究了使用镁铝水滑石去除水溶液中的阴离子污染物，如溴化物，硫酸盐，硝酸盐，氟化物和氯化物。目前的研究分析了煅烧对水滑石阴离子去除效率的影响。水滑石样品已在马弗炉中在不同温度下分批煅烧，并添加到锥形烧瓶中的各种阴离子溶液中，并在摇动培养箱中保持搅拌三小时。然后使用离子色谱法分析获得的滤液。获得的结果表明，随着煅烧温度的升高，阴离子去除量稳步增加。所有研究中的阴离子均显示出对煅烧样品的去除率高于未煅烧样品。对于煅烧和未煅烧样品，^- >氯^- >溴^- > NO ₃ ^- > SO ₄ ^2- 其中明确指出，煅烧不影响此行为和离子半径是一个影响因素，即使没有煅烧。