采用活化稻壳作为吸附剂纯化废液,再利用其去除石英砂中铁杂质。吸附剂的制备是在110℃下,质量分数1%的KOH溶液活化稻壳1 h,然后于600℃热处理2 h。研究了KOH的浓度、吸附剂的量、吸附时间、吸附液初始浓度和温度参数对去除废液中铁和铝的影响。结果表明,在最优试验条件下,铁和铝的去除率分别为97.2%和94.2%。研究发现纯化的废液对石英砂中铁的去除率远高于未纯化废液;在额外添加3.6%的磷酸时,纯化废液对铁的去除率达到77.1%,这项技术不仅可以节省大量的水(966 kg/m3)和磷酸(57.8 kg/m3)还可以避免环境污染。
The present study was undertaken to purify waste solution using activated rice husk as an adsorbent for reuse in removal of impurity iron from quartz.The adsorbent was prepared by chemical activation of rice husk with 1% KOH at 110 ℃ for 1 h and then thermal at 600 ℃ for 2 h.Several parameters such as KOH concentration,adsorbent dose,contact time,temperature and initial metal ions concentration on the removal of Fe3+ and Al3+ from waste solution were investigated.The results showed that the removal efficiencies were 97.2% and 94.2% for Fe3+ and Al3+ respectively,under optimized conditions.It was found that iron removal efficiency from quartz by purified waste solution was far superior to that by waste solution;Iron removal efficiency can be reached 77.1% at the concentration of additional of phosphoric acid was 3.6% in purified waste solution,which not only can saved a lot of water(966 kg/m3) and phosphoric acid(57.8 kg/m3),but also avoid environmental pollution.