Department of Natural Resources and Environmental Design, North Carolina A&T State University, Greensboro, North Carolina, USA.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2011;46(4):408-14. doi: 10.1080/02773813.2010.542398.
The major objective of this research was to investigate the efficiency of zeolite in the removal of NH(4)-N from swine wastewater and desorption of the sorbed NH(4)-N from the zeolite saturated with N. Sorption experiments were conducted on the sorbents, zeolites I, II and III. Zeolites II and III which are natural and unmodified, showed better sorption (4400-4500 mg kg(-1) with 500 mg L(-1) feed concentration) compared to Zeolite I (3053 ± 127 mg kg(-1) with 500 mg L(-1) feed concentration), which is a surfactant modified zeolite. Freundlich and Langmuir isotherms were plotted from the sorption experimental data. Column studies indicated that, columns with flow rates of 2 and 3 mL min(-1), reached the breakthrough point within about 100 h. The possibility of regeneration of the column material was investigated by flushing the column with 0.1 N HCl. The results from this experiment showed that even after desorption with DI water for more than 250 h, considerable amount of N was still available in the column that was available for desorption by 0.1 N HCl. This confirms that zeolite could be a good substrate for slow N release in soil. The application of Zeolite II for the NH(4)-N removal from swine wastewater supports this observation.
本研究的主要目的是研究沸石从猪废水中去除 NH(4)-N 的效率以及从被 NH(4)-N 饱和的沸石中解吸 NH(4)-N 的效率。在吸附剂沸石 I、II 和 III 上进行了吸附实验。与沸石 I（500 mg L(-1) 进料浓度下的 3053 ± 127 mg kg(-1)）相比，天然且未经修饰的沸石 II 和 III 表现出更好的吸附能力（500 mg L(-1) 进料浓度下的 4400-4500 mg kg(-1)）。表面活性剂修饰的沸石 I。从吸附实验数据绘制了 Freundlich 和 Langmuir 等温线。柱研究表明，流速为 2 和 3 mL min(-1) 的柱子在大约 100 小时内达到了突破点。通过用 0.1 N HCl 冲洗柱子来研究柱材料再生的可能性。该实验的结果表明，即使在 DI 水冲洗超过 250 小时后，仍有相当数量的 N 仍存在于柱中，可通过 0.1 N HCl 进行解吸。这证实了沸石可以作为土壤中缓慢 N 释放的良好基质。沸石 II 用于从猪废水中去除 NH(4)-N 的应用支持了这一观察结果。
