The removal of nickel ions with walnut shell

The present study was aimed at determining whether walnut shell would have acceptable adsorption efficiency for removing Ni (II) and thereby offer an effective and economical alternative to more expensive treatments. This paper describes the removal of Ni (II) ions from aqueous solutions containing 100 mg L-1of nickel using walnut shell. The effects of various parameters such as optimum adsorbent mass, contact time, pH of the medium were investigated. The maximum removal efficiency of 43.23% was obtained at a pH of 5.85 with a 5-min contact time for a 5 mg L-1solid-to-liquid ratio and an initial heavy metal concentration of 100 mg L-1. it can be concluded that walnut shell could be used as a low-cost and abundant source for the removal of Ni (II), and as an alternative to more costly materials such as ion-exchange resins and activated carbon. It is thought that it will be possible to make walnut shell modification studies in order to obtain higher increases in recovery efficiency.