典型土壤矿物吸附有机阳离子染料废水对比研究

Comparative Study on Adsorption of Organic Cation Dye Wastewater by Typical Soil Minerals

为了探究不同土壤矿物类型、温度及pH值等外界条件不同对矿物吸附能力的影响,通过对比实验,以亚甲基蓝、结晶紫两种典型阳离子染料为代表,选用α-石英、α-方石英、无定形二氧化硅、蒙脱石、高岭石等典型土壤矿物,分别在20℃、25℃、30℃温度条件及pH=3、pH=7、pH=11条件下进行了吸附对比实验研究。结果表明:几种典型土壤矿物对亚甲基蓝、结晶紫的吸附能力明显不同,具体为:无定形二氧化硅>蒙脱石>高岭石>α-石英>α-方石英。在一定范围内,温度越高,矿物的吸附能力越强,且在碱性条件下各矿物对染料废水的吸附效果更佳。从对比的角度出发,分析同一条件下不同矿物对有机阳离子染料的吸附能力,定性分析不同矿物组成对土壤自净能力的贡献,从而为评估不同类型土壤对染料废水的净化能力提供一定的理论依据。

In order to explore the effects of different soil mineral types,temperature,and pH on the adsorption capacity of minerals through comparative experiments,methylene blue and crystal violet are two typical cationic dyes.Five typical soil minerals?such as a-quartz,a-cristobalite,amorphous silicon dioxide,montmorillonite and kaolinite were subjected to adsorption comparison experiments under the temperature conditions of 20℃,25℃,and 300℃ and pH=3,pH=7,and pH=11,respectively.As a result,these typical soil minerals have apparently different adsorption capacity on methylene blue and crystal violet.Specifically,the sequence of the adsorption capacity was amorphous silicon dioxide>montmorillonite>kaolinite>α—quartz>α-cristobalite.Furthermore,to some extent,a higher temperature would promote the adsorption and a higher adsorption amount could be obtained under the alkaline condition.The adsorption capacity of different minerals toward dye waste water under same conditions was analyzed.In this way,the contribution of different mineral compositions to soil self—purification ability was also qualitatively analyzed,so that some theory basis for evaluating the purification ability of different soil types towards dye waste water could be provided.