Journal of Mechanical Engineering Vol SI 2 (1), 113-125, 2017 ____________________ ISSN 1823-5514, eISSN 2550-164X Received for review: 2016-12-07 © 2017 Faculty of Mechanical Engineering, Accepted for publication: 2017-01-20 Universiti Teknologi MARA (UiTM), Malaysia. Published: 2017-05-15 Bio-Recovery of Silver from Simulated Silver Electroplating Wastewater Using Palm (Elaeis guineensis) Leaves Extract Ahmad Arif Junaidah Jai Norashikin Ahmad Zamanhuri Faculty of Chemical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Malaysia ABSTRACT In this research, the role of an eco-friendly biomaterial, palm (Elaeis guineensis) leaves extract as a reducing and stabilizing agent to recover precious metal silver from simulated silver electroplating wastewater, was studied. The phytochemical compounds present in the palm leaves extract, which possesses antioxidant properties, were characterized according to their functional groups and the parameters involved in affecting the silver bio-recovery effectiveness were investigated. The studies found that major types of phytochemical compounds that assist silver bio-recovery were polyphenols, alcohols, carboxylic acid and reducing sugars. Meanwhile, the parameters of reactant’s concentration ratio, acidity and metal impurities were found to absolutely affect the silver bio-recovery effectiveness. The characterization of the recovered suspended solid particles after the bio- reduction process reveals that silver metals with high degree of crystallinity were successfully recovered and in nano-sized. Keywords: Palm Leaves Extract, Natural Antioxidant, Silver Wastewater, Bio-Recovery, Silver Nanoparticles. Introduction Electroplating is the application of a metal coating onto a metallic or other conducting surfaces by an electrochemical process [1]. This process however could generate a lot of metal wastes mainly in rinsewater and spent electroplating bath solution [2]. For common metals, it is still acceptable to