Gbarakoro S. L., Okorosaye-Orubite K.
Abstract: In this work potassium ions present in coconut (cocos nucifera L.) coir was used for the extraction of silver from waste x-ray films. Alkaline solutions of coconut coir ash were prepared by dissolving, 20, 40, 60, 80 and 100g of ash separately in 500ml of distilled water for 48 hours with stirring at intervals, followed by filtration. pH of the alkaline solutions obtained after standardization were 12.0, 12.4, 12.5, 12.5 and 12.7 respectively. These solutions were used to leach silver from the x ray films. Addition of 100ml of 1.5M sodium sulphide to the extracts produced precipitates in each beaker which were analyzed using Atomic Absorption Spectrophotometer model GBC Avanta Version 2.02. Silver ion concentration in each extract was obtained as 3.757, 3.989, 4.059, 4.317 and 4.876ppm respectively. The results show that more grams of the coconut coir ash produce more aqueous extracts which eventually stripped higher quantity of silver from the x-ray films. This work has therefore shown utility of a waste material for extraction of silver from waste x-ray films.
Keywords: Coconut coir ash extract, waste x-ray films, silver, AAS, potassium ion