酸化油页岩灰吸附Ni(Ⅱ)的研究

Study on the adsorption of nickel(Ⅱ)by using acid-treated oil shale ash

采用质量分数为50%的HNO3制备酸化油页岩灰吸附剂,研究吸附时间、吸附温度、Ni(Ⅱ)初始浓度、溶液pH值、吸附剂投加量和吸附剂粒径对酸化油页岩灰吸附性能的影响。结果表明,一定范围内,酸化油页岩灰吸附剂的吸附量(Qe)随吸附温度、Ni(Ⅱ)初始浓度、溶液pH值、吸附剂投加量的增加而增加,随吸附剂粒径的增加而减小。吸附温度对吸附剂的最大吸附量Q有明显影响,当Ni(Ⅱ)初始质量浓度为100mg/L,溶液pH值为6.0,吸附剂粒径为53～75 μm,吸附剂投加量为16.0∥L,吸附搅拌速度为400 r/min时,25℃、30℃、35℃下酸化油页岩灰的最大吸附量Q分别为17.0 mg/g、33.2 mg/g、42.9mg/g,且吸附主要以离子交换的化学吸附方式为主。酸化油页岩灰吸附剂对Ni(Ⅱ)的吸附符合Langmuir等温吸附方程,温度为25℃、30℃、35℃,溶液pH值为6.0,油页岩灰吸附剂投加量为16.0g/L,油页岩灰吸附剂粒径为53～75μm条件下,酸化油页岩灰对Ni(Ⅱ)的最大吸附量Q分别为17.0 mg/g、33.2 mg/g、42.9 mg/g。研究表明,油页岩灰经过酸化改性后可作为吸附剂处理含Ni(Ⅱ)废水,具有较好的市场应用前景。

This paper is inclined to present our research results on the adsorption of nickel（ Ⅱ） by using acid-treated oil shale ash, an inorganic byproduct of oil shale burning. For the purpose of our research, we have prepared acid-treated oil shale ash adsorbent from oil shale ash modified by 50% HNO3 solution. We have also discussed the effect of adsorption time, the nickel （ Ⅱ ） initial concentration, adsorption temperature, pH value, the adsorbent dosages and the panicle size in a series of adsorption experiments of ours. The results of our experiments and analysis show that the adsorption capacity （Qe） was found to rise with the increase of the adsorption temperature, the nickel （ Ⅱ ） initial concentration, adsorbent dosages and pH, but drop with the increase of the particle size of absorbent. In addition, the adsorption temperature was also found significantly affecting the maximum loading capacity of the adsorbent （ Q ）. When the nickel（ Ⅱ ） initial concentration was 100 mg/L, the pH value was 6.0, the panicle size was 53 -75 μm with the adsorbent dosage being 1.60 g/L and the agitation speed being 400 r/min, the maximum loading capacity of the adsorbent （Q） would be 17.0 mg/g （25 ℃）, 33.2 mg/g （30℃）, 42.9 mg/g （35℃）, with the mostly chemical adsorption of ion being exchanged. We have also found that Langmuir adsorption model can be used properly to meet the needs of the adsorption isotherms. The results obtained in the research has proven that the acid-treated oil shale ash adsorbent could be used as a favorable adsorbent for removing nickel（ Ⅱ） from the industrial and living sewage.