화학공학소재연구정보센터
Powder Technology, Vol.178, No.1, 51-55, 2007
Preparation of silver powders in micron size from used photographic films via leaching-cementation technique
The results of a leaching study of used photographic films containing silver with nitric acid are presented. Effect of reaction time, reaction temperature and acid concentration on silver dissolution efficiency was determined. The results obtained show that leaching of about 98% of silver is achieved using -2 mm spent (used) photographic film size at a reaction temperature of 90 degrees C for 50 min reaction time with 6% nitric acid concentration. Different solid:liquid ratios of 1:10 to 1:50 g/ml were also studied. Cementation study indicates that practically 100% of silver is deposited with addition of Zn metal powder. SEM photomicrographs show that sphere particles of about 1 mu m diameter were obtained. (c) 2007 Elsevier B.V. All rights reserved.