عنوان مقاله [English]
Industrial waste water usually has metal ions which can be harmful for human and other animals over the optimum level. In this study, removal of metal ions such as lead, copper and zinc from waste water using tree leaves were investigated aimingto introduce the cheap, effective and accessible adsorbents as compared to conventional adsorbents. For this aim 5 g of three softwoods leaves, namely Pinus sylvestris, Cupressus sempervirens and Cupressus laxuses from western Mazandaran province were selected, Then, 200 ml waste water containing metal ions such as lead, copper and zinc were prepared in specific concentrations and regulated at pH=5. The removal of metal ions from wastewater were tested in 30, 60, 90, 120 and 150 minutes. The result indicated significant differences between species and various removal time in 99% statistical confidence level; however Pinus sylvestris’ leaf had highest removal rate for lead, copper and zinc as 81.2, 63.9 and 56 percent, respectively. Also, the optimum connection time for removal of metal ions from two softwood species, Pinus sylvestris and Cupressus laxuses was 90 minutes which was 60 minutes for Cupressus sempervirens. In general, the leaf of Pinus sylvestris has approximately equal efficiency in removing of metal ions, compared to the laboratory scale adsorbent (active carbon), which makes it more suitable regarding economical and environmental aspects.