表面活性剂对2,4-二氯苯酚在黄土中吸附行为的影响

Effect of surfactant on sorption behavior of 2,4-dichlorophenol in loess soils.

研究了用阳离子表面活性剂单独改性和用阴、阳离子表面活性剂共同改性的黄土对水中2,4-二氯苯酚的吸附行为以及环境pH值和离子强度的影响.结果表明,天然黄土对2,4-二氯苯酚的等温吸附曲线满足Freundlich方程;改性后的黄土对2,4-二氯苯酚的吸附能力明显增强,吸附率提高2～9倍,且随着阳离子表面活性剂加入量的增多而增大,等温吸附曲线与天然黄土有所不同,并且阴离子表面活性剂的存在会减小相应阳离子表面活性剂改性黄土对2,4-二氯苯酚的吸附;随着pH值的逐渐增大,2,4-二氯苯酚的离子形态逐渐增多不利于改性黄土对2,4-二氯苯酚的吸附,而离子强度对吸附的影响程度却随着pH值的逐渐增大而增强.

The effect of loess soils, modified individually with cation surfactant and combinedly with anion and cation surfactants, on the sorption behavior of 2,4-dichlorophenol in water, and also on the pH and ionic strength in environment were studied. The results showed that the sorption isotherm of 2,4-dichlorophenol on natural loess soils filled Freundlichequation; the capacities of the modified loess soils on 2,4-dichlorophenol markedly increased with its rate raised to 2~9 times and increased with the adding quantity of the cation surfactants; its sorption isotherm was different from the natural loess soil and in the existence of anion surfactant it was sure to reduce the sorption; with gradual rise of pH value, the ionic form of 2,4-dichlorophenol gradually increased, which is not favourable to the modified loess soil sorption of2,4-dichlorophenol, while the effect degree of ionic strength on sorption was increased.