反应条件对镁铝水滑石制备和吸附性能的影响

Effect of Reaction Conditions on Preparation and Adsorption Properties of Mg-Al Hydrotalcite

以MgSO4和Al2(SO4)3为原料,尿素CO(NH2)2作沉淀剂,采用均匀共沉淀法制备镁铝水滑石。利用XRD、SEM、FT-IR对产物进行表征,探讨尿素用量和晶化温度对水滑石物相组成、微观结构的影响;考察了反应条件(尿素用量和晶化温度)对水滑石吸附盐酸四环素性能的影响。结果表明,均匀共沉淀法合成的镁铝水滑石具有特征的层状和片状结构。随尿素用量增加、温度升高,水滑石晶面层间距增加,结晶度提高。在尿素用量为n尿素∶nSO4^2-=4∶1,晶化温度为110℃的条件下,镁铝水滑石对盐酸四环素有最好吸附效果,其吸附率为70.82%。

Magnesium-aluminum hydrotalcite was prepared by uniform co-precipitation method using MgSO4 and Al2(SO4)3 as raw materials and CO(NH2)2 as precipitant.The product was characterized by X-ray diffraction(XRD),fourier transform infrared spectra(FTIR)and scanning electron microscope(SEM).The effects of urea crystallization temperature and the different urea dosage on the microstructure of Mg-Al hydrotalcite were studied.The effect of reaction conditions on the adsorption properties of Mg-Al hydrotalcite were investigated by using tetracycline hydrochloride as adsorbent.The results showed that the magnesium-aluminum hydrotalcite had characteristic layered and flaky structure,synthesized by uniform coprecipitation method.With the increase of urea dosage,the spacing of hydrotalcite layer increases,the crystallinity became better.And the layer spacing increased with crystallization temperature increasing.The maximum adsorption rate of tetracycline hydrochloride on Mg-Al hydrotalcite was 70.82%at 110℃and nurea∶nSO4^2-=4∶1.