铝灰渣为原料的水滑石合成及其吸附性能研究

Synthesis of Hydrotalcite-Like Slag from Aluminum Dross and Its Adsorption Properties

铝灰渣为铝工业生产中伴生的危险固废物,其产量巨大且含有大量的铝资源,合理利用铝灰渣有非常重要的意义。以铝灰渣为原料合成锌铝水滑石,分别用氢氧化钠和盐酸提取得到铝灰渣的提取液,再使用热水法成功合成锌铝水滑石,并探究合成时间、合成温度,以及使用两种不同提取液对合成的锌铝水滑石结晶度的影响。结果表明:延长反应时间和提高反应温度有利于晶体的生长,但过高反应温度会破坏锌铝水滑石晶体而变为其他产物;使用碱提取液合成的锌铝水滑石,其结晶度较好;同时,探究了不同条件下合成的样品对F-的吸附量,当使用碱提取液合成的锌铝水滑石在合成时间为6 h、合成温度为130℃条件下,F-的吸附量最大为18.3 mg·g^(-1);XRD和SEM结果显示,使用氢氧化钠提取液合成的锌铝水滑石的结晶度和晶粒尺寸均较好。

With the continuous development of aluminum industry,the output of aluminum profiles continues to increase,and aluminum dross is an inevitable by-product in the production process.As a solid waste,aluminum dross contains a large amount of aluminum resources.Therefore,aluminum dross is used reasonably has a very important meaning.In this paper,we plan to use aluminum dross as raw material to synthesize zinc-aluminum hydrotalcite,and use sodium hydroxide and hydrochloric acid extractant to obtain the extract of aluminum dross,and successfully synthesize zinc-aluminum hydrotalcite by hot water method.Using the influence of the crystallinity of the zinc-aluminum hydrotalcite synthesized by the two extracts,the results show that prolonging the reaction time and reaction temperature is conducive to the growth of crystals,but the zincaluminum hydrotalcite crystals are destroyed at too high reaction temperature and become other products,And the adsorption capacity of F−for the samples synthesized under different conditions was investigated.The results showed that the zincaluminum water slide synthesized by the alkaline extraction solution had the largest adsorption capacity of F−at the synthesis time of 6 h and the synthesis temperature of 130℃,which was 18.3 mg∙g^(−1);in addition,XRD and SEM results show that the crystallinity and grain size of the zinc-aluminum hydrotalcite synthesized by the extracted solution using sodium hydroxide extractant are better.