The Adsorption Performance of Urtica dioica on the Removal of Cadmium from Aqueous Solutions

Abstract

Many contaminants (dyes, heavy metals and some inorganic substances) occur naturally through processes such as the weathering of rocks and human activities including the mining, processing and smelting of ore, and the nuclear and automotive industries. The release of contaminants, especially heavy metals to the media without any remediation process, has a very harmful effect on the environment and human health. Recently, scientists have been researching various methods to purify heavy metals from wastewater. Adsorption is an efficient method and many of materials are used as an adsorbent; activated carbons, clays, biopolymers, agricultural wastes etc. Among them, biosorbents have been preferred as they are cheap, practical, easy to find and environmentally friendly. In this study, the adsorption potential of Urtica dioica (U. dioica) on the removal of cadmium, one of the most dangerous poisons for the organisms and their environment, was investigated. The fact that the plant has low specific weight, rich functional groups and also lignocellulosic, porous structure led to the idea that it may be suitable for adsorption. U. dioica was used without any chemical modification only after being dried and passed through a 0.5 mm sieve. The effect of pH (4-10), adsorbent dose (0.2-0.8 g) and metal solution concentration (50-150 mgL-1) on adsorption was investigated. The great adsorption performance of 95% was obtained at pH 10 with 150 mgL-1 metal solution concentration and 0.8 g adsorbent dose.