泥炭预处理吸附垃圾渗滤液中的COD

Pretreatment Adsorption of Organic Matter from Landfill Leachate with Peat

通过对泥炭改性去除水中COD进行了试验研究。探讨了磷酸、硫酸、盐酸、硝酸和氢氧化钠对COD去除效果的影响和吸附机理。结果表明,在酸、碱改性过程中,用5%的硫酸改性的泥炭去除COD的效果最佳,改性泥炭用量为每10 g/100 mL,吸附时间为60 min,pH为10的试验条件下,COD的去除率为68.5%以上,磷酸较硫酸次之,去除率为55%左右,而盐酸和硝酸较差分别为45%和38%,氢氧化钠为40%左右。并对其吸附机理进行了研究,其吸附等温线符合Freundlich型。通过扫描电镜观察泥炭表面的结构,硫酸改性后的泥炭表面结构比较粗糙,比表面积最大,与实验结果相吻合。用原子吸收法对泥炭处理前后的水样进行比较,表明泥炭对重金属也有很好的去除率。本研究为泥炭利用提供了可借鉴的思路。

Experimental study was done on COD removal from water by modified fabric peat. Effects of COD removal by phosphoric acid, sulfuric acid, hydrochloric acid, nitric acid and sodium hydroxide as well as mechanism of adsorption were discussed. Results showed that the best modified method was using sulfuric acid with concentration of 5%, with removal rate of COD 68.5% under the conditions of dose of modified fabric peat 10 g/100 mL, adsorption time 60 min and pH value 10, followed with removal rate of COD by phosphoric acid as 55%, while that by hydrochloric acid and nitric acid as 45% and 38% respectively, and by sodium hydroxide as 40%. Its adsorption mechanisms were studied, with their adsorption isotherms in line with Freundlich type. The structure of the peat surface was observed by scanning electron microscope, from which rough surface structure and largest surface area has been found for peat modified by sulfuric acid, which fit the experimental results. Compared water samples before and after peat treatment by atomic absorption spectrometry, it showed the removal of heavy metals by peat were significantly.