Extraction of heavy metals from compost using a mixture of Na2EDTA and Na2S2O5: column studies

this study reports on a method to extract heavy metals from compost. compost samples were initially characterized to determine the type and content of heavy metal compounds. column studies were carried out by solid liquid extraction method using 0.01 m na2edta-0.1 m na2s2o5 solution. target heavy metal removal efficiencies were achieved for cu (72%), zn (77%), pb (47%), cd (86%), but not for ni (12%) after160 minutes contact time at a solid:liquid ratio of 1:15 g ml and 360 ml solution volume.