改性沸石对氨氮去除效果与机理研究

目的]研究改性沸石对废水中氨氮的去除效果及吸附机理。方法]采用脱磷尿液作为试验废水,比较了不同改性沸石(NaCl沸石、HCl沸石、HCl-焙烧沸石和HCl-焙烧-微波沸石)对试验废水中氨氮的去除效果,并探讨了其吸附机理。结果]在粒径为0.5～1.0 mm,投加量为200 g/L时,天然沸石和4种改性沸石对氨氮的平衡吸附量依次为天然沸石饱和NaCl改性沸石5.0%HCl改性沸石5.0%HCl-400℃焙烧改性沸石5.0%HCl-400℃焙烧-微波改性沸石。沸石扫描电镜影像和质量损失揭示吸附差异的主要原因是不同改性方法导致沸石孔隙大小和数量的差异。结论]5.0%HCl-400℃焙烧-微波改性沸石对氨氮具有较高吸附能力,平衡吸附量为17.9 mg/g,是天然沸石的2.6倍。

Adsorption Effect and Mechanism of the Ammonia Nitrogen by Modified Zeolite

Objective ] The research aimed to study adsorption effect and mechanism of the ammonia nitrogen in wastewater by modified zeo- lite. Method ] Dephosphorization urine as experimental wastewater, removal effect of the ammonia nitrogen in test wastewater by different modified zeolite （NaC1 zeolite, HC1 zeolite, HC1- calcination zeolite and HC1- calcination- microwave zeolite） was contrasted, and adsorp- tion mechanism was discussed. Result] When particle size was during 0.5 - 1.0 mm, and dosage was 200 g/L, equilibrium adsorption ca- pacity order of the ammonia nitrogen by natural zeolite and 4 kinds of modified zeolite was natural zeolite 〈 saturated NaC1 modified zeolite 〈 5.0% HC1 modified zeolite 〈 5.0% HC1 - 400 ℃ calcination modified zeolite 〈 5.0% HC1 - 400 ℃ calcination - microwave zeolite. Scan- ning electron microscopy image and mass loss of the zeolite revealed main reason for adsorption difference. That is, different modified methods caused that size and amount of the zeolite pore had significant differences. Conclusion ] 5.0% HC1- 400 ~C calcination- microwave zeolite had higher adsorption capability. Its equilibrium adsorption capacity was 17.9 mg/g, which was 2.6 times of the natural zeolite.