汞在泥炭上的吸附特征研究

Characteristics of Adsorption and Desorption of Mercury on Peat

采用批次法研究了汞在三江平原泥炭、吉林双阳泥炭上等温吸附特征及介质pH值、背景离子浓度的影响。实验结果表明:两种泥炭吸附等温线均同时符合Langmuir和Freundlich等温吸附方程,而与Langmuir方程的拟合效果更好; 在溶液汞浓度相同时,温度升高,泥炭对汞的吸附量降低;在相同的条件下,三江平原泥炭对汞的吸附量大于吉林双阳泥炭对汞的吸附量;两种泥炭对汞的吸附量受pH值的影响明显且都在pH 6.0左右具有最大的吸附量;在酸性条件下,吸附介质的pH值升高利于泥炭对汞的吸附;介质的离子浓度升高,可以使两种泥炭对汞的吸附量迅速降低。

The isotherm characteristics of mercury adsorption on the Sanjiang Plain and Jilin Shuangyang peats and the influences of temperature, pH and ion strength were studied using the batch method. The results showed that both isotherms of mercury on two kinds of peat conformed to Langmuir and Freundlich Equation, but Langmuir equation was better. The increasing temperature could decrease the amount of mercury adsorbed on peat at the same mercury concentration in solution. Amount of mercury adsorbed on the Sanjiang Plain peat was larger than that on the Jilin Shuangyang peat. The pH value of solution affected the amount of the mercury adsorption on peat obviously. Mercury sorption had the maximum value at about pH 6.0. Rising pH was useful to mercury sorption on the peat in acid solution. The increased ion - concentration in solution maked the mass of the mercury adsorbed on two kinds of peat decreasing.