微波辐射回用活性炭对水中亚甲基蓝和Cd2＋去除效果的研究

考察了微波-活性炭联合处理技术对模拟染料废水中亚甲基蓝和Cd2＋的去除效果。对于100 mL浓度为1 000 mg/L的亚甲基蓝溶液、活性炭用量为10 g时,新活性炭对亚甲基蓝的去除率为99.99%;采用700 W微波对吸附亚甲基蓝的活性炭辐射10 min进行再生并回用,经微波辐射再生10次后活性炭对亚甲基蓝的去除率为99.68%,未经微波作用反复使用10次的活性炭对亚甲基蓝的去除率为85.41%。结果表明：微波处理有效地减缓了活性炭吸附能力的下降速率,实现了活性炭再生和反复使用。在吸附过程中,Cd2＋使活性炭对亚甲基蓝的吸附能力略有下降,而共存的亚甲基蓝则促进了活性炭对Cd2＋的吸附,对新炭和再生后活性炭物理化学特性的表征证明了活性炭对亚甲基蓝的吸附为物理吸附,对Cd2＋的吸附为化学吸附。

Study on removal effect of methylene blue and Cd~（2＋） with adsorption of recycled activated carbon by microwave irradiation

An integrated granular activated carbon（GAC） adsorption/microwave（MW） irradiation process was investigated for the removal of methylene blue（MB） or/and Cd2＋ from aqueous solution.The decoloration efficiency of 100 mL MB solution（1 000 mg/L） by 10 g new GAC was 99.99%.Under the conditions of MW power of 700 W and radiation time of 10 min,the saturated GAC was regenerated by MW irradiation,and being reused for adsorption.The GAC was reused and regenerated by MW irradiation for ten times,the decoloration efficiency of the tenth time regenerated GAC was 99.68%.Without MW irradiation,the decoloration efficiency of GAC was 85.41% at the tenth time.The results showed that microwave irradiation process could efficiently reduce the descent of adsorption capacity of GAC which lead to effective regeneration and reuse.The existence of Cd2＋ caused a little decrease of GAC adsorption to MB,while the existence of MB enhanced the adsorption of Cd2＋ on GAC.It was also demonstrated that the adsorption of MB on GAC was related to physical properties and that of Cd2＋ was related to chemical properties.