PENGEMBANGAN METODE ELEKTRODEPOSISI UNTUK PENGAMBILAN KEMBALI PERAK DARI LIMBAH FOTORONTGEN

Abstract

Silver in its ionic form is one of the heavy metals dangerous if it is discharged into the environment or into the body of humans or other living things. Silver metal pollution sources, one of which comes from waste fixer which is a waste from the photorontgen process. However, silver in its metal form has a high economic value. Therefore, the development of techniques or methods of recovering silver from the waste solution and turning it into a metal form is important to do so that the metal does not pollute the environment and can be reused economically. One method that can be done is by electrolytic deposition or electrodeposition in which silver in the form of a silver thiosulfate complex compound in the photorontgen waste is converted to Ag metal through a redox reaction. To obtain good quality and quantity of silver deposits in the electrodeposition process, it is necessary to optimize several factors that influence, among others, optimization of potential difference, time and pH of the solution. This study aims to determine the effect of potential difference, time and pH of the solution on the efficiency of the electrodeposition process. Electrodeposition efficiency was determined based on the percentage of reduced silver mass calculated from the decrease in Ag concentration in photorontgen waste solution before and after the electrodeposition process. Based on the results of the study obtained the optimum electrodeposition process at a potential difference of 8 V for 75 minutes and the pH of the waste is 3, where the mass percent of silver which is reduced from waste is 86.49%.