Ni removal by adsorption using oil palm fibre

Nickel (Ni) is present in wastewaters of a number of industries e.g. steel, electroplating, batteries manufacture, etc. Conventional heavy metal removal technologies such as ion exchange, chemical precipitation, reverse osmosis, etc. are often ineffective or expensive. Adsorption is a commonly used method for the removal of heavy metals from aqueous solutions. However, for the process to be economical, the adsorbent should be easily and cheaply available in abundance and it should require minimal pretreatment; for expensive pre-treatment procedures would add to the overall treatment cost. This work describes the use of a locally available low cost adsorbent, oil palm fibre, for the removal of Ni from aqueous solution. The oil palm fibre was obtained from a local palm oil factory and was treated with concentrated sulphuric acid prior to its use as adsorbent. A series of batch studies, using 250 ml Erlenmeyer flasks and an orbital
shaker, was conducted to evaluate the effect of agitation time, pH and adsorbent mass on the removal of Ni. Isotherms were generated to describe the removal of the metal. The results show that the treated fibre was an effective adsorbent for the removal of Ni. The optimum agitation time and optimum pH were 90 minutes and 7 respectively. The Ni adsorption pattern followed the Freundlich isotherm closely.