NGHIÊN CỨU KHẢ NĂNG HẤP THU KIM LOẠI NẶNG TRONG NƯỚC THẢI CỦA XƠ DỪA HOẠT HÓA

Coir is a cheap material has a high ability to absorb heavy metals. The research results showed that in the single - pollutant environment where metals like Pb, Cu, Zn, Cd and As have the content of 5 mg/litre per each and an amount of activation coir put into to treat waste water is 5g/litre,the activated coir could absorb very well Pb, Cu, Zn and Cd. Specifically, the coir could absorb 99.46% of Pb; 80.06% of Cu; 77.82% of Cd and 61.22% of Zn; however, it absorbs very small amount of As (11.40%). At the same time, the pH of the sewage environment also increases by nearly 3 units. When increasing pollution concentration to 50 mg/litre, the Coir’s efficiency of absorbing Pb, Cu, Zn and Cd is extremely reduced. The pH of the environment experiences very little change. In the assuming environment where pollutant mixture was 100 times higher than the allowed level in the Vietnamese standard (QCVN 24:2009), the coir could hardly absorb heavy metals, and the environment’s pH would be changed very little, except for Cd (the pollutant concentration which is 100 times higher than the allowed level in the Vietnamese standard is just 1 mg/litre, so a replacement of Na in the coir structure occurs).