Multivariate Optimization of Adsorption Parameters For Removal of Zn(II) From Waters By MgO Nanoparticles

In 1978, the United States environmental protection agency (USEPA) prepared a list of 129 organic and inorganic pollutants found in wastewater that constitute serious health hazards. This list, known as the Priority Pollutants List, includes the following thirteen metals:antimony, arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium,silver, thallium, and zinc [1]. Unlike organic compounds, metals are non-biodegradable and,therefore, must be removed from wastewater .Zinc is present in the air, soil, water and almost all food. Zinc is naturally released into the environment, although industrial activities are mostly responsible for zinc . In this study , MgO nanoparticles were used for removal of Zn(II) in a batch system. The main effective variables on removal efficiency (R%) and capacity uptake (q) such as: contact time (t), sorbent dosage (m) and initial concentration of Zn(II) at two low and high levels was investigated. Response surface methodology (RSM) involving Box-Behnken design (BBD) was employed to optimize the removal efficiency percent (R%) and capacity uptake (q) of Zn(II). The kinetic and thermodynamic studies of Zn (II) adsorption onto the nano-sorbent were carried out. Second-order kinetic model showed more favourability for dynamic behaviour of current adsorption process. The presence of Na+, K+,Ca2+ and Mg2+ ion have been shown no significant interference on adsorption efficiency. FT-IR analysis identified that the functional group of sorbent were involved in the adsorption process.