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

摘要:

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。

Abstract:

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 zinc-aluminum 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 zinc-aluminum 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.