沸石复合颗粒材料的制备方法优选及其脱氮除磷性能研究

开发一种具备氮、磷双重吸附能力的富营养化水体修复材料，以沸石为原料，将天然沸石碱洗后与Ca(OH)₂、膨润土进行混合，再通过调整混料比例、煅烧温度、煅烧时间、升温速率等过程，筛选出既具有脱氮、除磷能力，又具有一定机械强度的复合颗粒材料. 结果表明:复合颗粒材料最佳制备条件为沸石、Ca(OH)₂、膨润土混料质量比20︰1︰2，煅烧温度504 ℃，煅烧时间1.2 h，升温速率5.6 ℃·min?1. 通过单因素实验和相关性分析表明，各因素对材料磷酸盐吸附量、氨氮吸附量、散失率均有不同程度的影响，其中Ca(OH)₂与磷酸盐、氨氮吸附量均具有显著相关性. 当初始氮、磷质量浓度为25 mg·L?1时，新型复合材料对磷酸盐和氨氮理论吸附量分别为4.39、4.01 mg·g?1，去除率分别可达到87.7%和80.1%，散失率为11.4%. 

Optimized preparation,nitrogen and phosphorus removal capacity of zeolite composite particulate materials

A repair material with simultaneous nitrogen and phosphorus removal capacity was developed in this study to treat water eutrophication. Raw material zeolite was mixed with calcium hydroxide and bentonite after soaking in alkali solution for 24 h. The obtained particulate composite materials were screened for removal of nitrogen and phosphorus, and for mechanical strength. Mixture ratio, calcination temperature, calcination time, heating rate and other processes were adjusted. Optimal conditions for preparation of particulate composite material were found: zeolite, Ca(OH)₂, bentonite mixture ratio 20︰1︰2, calcination temperature 504℃, calcination time 1.2 h, heating rate 5.6℃·min?1. Single-factor experiments and correlation analysis revealed that preparation conditions influenced adsorption and removal rate of phosphate and ammonia nitrogen. Ca(OH)₂ was found to have significant correlation with adsorption of phosphate and ammonia nitrogen. With initial phosphorus and nitrogen concentrations both at 25 mg·L?1, adsorption capacity of the new composite material was 4.39 and 4.01 mg·g?1, respectively. Removal rate was 87.7% and 80.1%, respectively. Loss rate was 11.4%.