Zeng Le
Alberta Research Council Inc. P.O. Box 4000, AB T9C 1T4, Vegreville, Canada.
Water Res. 2003 Nov;37(18):4351-8. doi: 10.1016/S0043-1354(03)00402-0.
A method for preparing iron(III)-based binary oxide adsorbents in a granulated form for arsenic removal was studied. The key step in the method was the simultaneous generation of hydrous ferric oxide (FeOOH) sol and silica sol in situ in one reactor. This eventually led to the formation of Fe-Si complexes. The addition of silica enhanced the granulated adsorbent strength but reduced the arsenic adsorption capacity. An optimum Si/Fe molar ratio in the balance of adsorbent strength and arsenic adsorption capacity was found to be approximately 0.33. The effects of aging time, drying temperature and process pH on adsorbents were also evaluated in the study. X-ray diffraction analysis confirmed that the iron(III) oxide in the Fe-Si binary oxide adsorbents was amorphous, largely due to the retardation of the iron oxide crystallization by the presence of silicate species. The surface area of the Fe-Si adsorbents and the particle size of Fe-Si complexed suspensions were determined as well. The batch strength testing procedure introduced in this study can provide a simple and quick evaluation of granulate strength in a wet status. Generally, this developed method can prepare granulated Fe-Si binary oxide adsorbents for column adsorption of arsenic from water.
研究了一种制备粒状铁（III）基二元氧化物吸附剂用于去除砷的方法。该方法的关键步骤是在一个反应器中原位同时生成水合氧化铁（FeOOH）溶胶和硅溶胶。这最终导致形成Fe-Si络合物。二氧化硅的添加增强了粒状吸附剂的强度，但降低了砷的吸附容量。发现在吸附剂强度和砷吸附容量之间达到平衡的最佳Si/Fe摩尔比约为0.33。该研究还评估了老化时间、干燥温度和工艺pH对吸附剂的影响。X射线衍射分析证实，Fe-Si二元氧化物吸附剂中的氧化铁是无定形的，这主要是由于硅酸盐物种的存在阻碍了氧化铁的结晶。还测定了Fe-Si吸附剂的表面积和Fe-Si复合悬浮液的粒径。本研究中引入的批量强度测试程序可以对湿态下的颗粒强度进行简单快速的评估。一般来说，这种开发的方法可以制备用于从水中柱吸附砷的粒状Fe-Si二元氧化物吸附剂。
