新型粉煤灰陶粒对水中Cu(Ⅱ)的去除特性及吸附等温模拟

Characteristics of Cu(Ⅱ) removal in wastewater by new fly ash ceramisite and its adsorption isotherm simulation

以粉煤灰、膨润土等制备新型粉煤灰陶粒,考察粉煤灰陶粒对溶液中Cu(Ⅱ)的去除特性并进行吸附等温线拟合。结果表明,粉煤灰陶粒对Cu(Ⅱ)的去除主要为吸附过程,对Cu(Ⅱ)的吸附效果与陶粒用量、温度及振荡速度有关,较大的粉煤灰陶粒用量、适宜的温度及振荡有较好的Cu(Ⅱ)去除效果。当温度为25℃、p H4.5及振荡速度150 r/min时,2.00 g粉煤灰陶粒对50 m L溶液中浓度为100 mg/L的Cu(Ⅱ)去除率为100%,而同等条件下两种普通市售陶粒的Cu(Ⅱ)去除率分别只有14.6%、6.3%。陶粒吸附柱可连续4次对250 m L浓度为100 mg/L的Cu(Ⅱ)去除率达90%以上。25℃时粉煤灰陶粒对Cu(Ⅱ)的最大吸附量为2.78 mg/g,其吸附过程符合Langmuir等温式,以Freundlich吸附等温式拟合则相关性较差。

A new kind of fly ash ceramsite was made with fly ash and bentonite. This paper studied the characteristics of the new fly ash eeramsite on the removal of Cu （ Ⅱ ） in wastewater and its adsorption isotherm simulation. The results showed that adsorption was the main process of Cu（ Ⅱ ） removal. The adsorption effect of Cu （ Ⅱ ） was related to the amount of ceramic, temperature and oscillation. Better removal of Cu （Ⅱ ） could be attained with the larger amount of fly ash eeremsite, appropriate temperature and oscillation. The Cu （Ⅱ） removal rate could reach 100% with the pH4.5, 25~C, 150 r/min and 2.00 g ceramsite, when the wastewater was 50 mL and the concentration was 100 mg/L, while the removal rate of two kinds of ordinary eeramsites was only 14.6% and 6.3% under the same conditions. The Cu （ Ⅱ ） removal rate of the ceramsite adsorption column could reach 90% above for 4 times continuously. The maximum adsorption capacity of Cu （Ⅱ ） was 2.78 mg/g. The adsorption process accorded with Langmuir adsorption isotherm, rather than Freundlich adsorption isotherm.