Othman, Norasikin and Tung, Chiong and Chan, Kit Hie and Goto, Masahiro (2004) The extraction of silver from photographic wastes by tetramethylthiuram disulfide. In: 18th Symposium of Malaysian Chemical Engineers (SOMChe) 2004, 13 - 14 Dec. 2004, UTP, Perak, Malaysia.
Waste generating from photographic industry contains metals, which are basically need to recover due to either economic reasons or to treat and remove the toxic metals before it can discharge into environment. Extraction of silver from this waste is very attractive. However, selection of the right technique is crucial in order to obtain relatively pure products. Solvent extraction may offer some advantages over other techniques. In solvent extraction process, selection of the right extractant, which offers high selectivity and capacity is important especially when involves extraction of metal from mixed diluted metals solution. Therefore, tetramethylthiuram disulfide as sulfur substitution extractant was examined in this study in term of its capability and selectivity in extracting silver from the photographic waste. It was found that the tetramethylthiuram disulfide is most promising extractant for extracting silver which is more than 90% of silver was extracted using only 0.03M extractant concentration. This result shows that extractants containing sulfur donor atoms have high selectivity towards silver than other metals. Stripping of extracted metals from organic-loaded metals solution using various stripping agents such as thiourea solution, nitric, hydrochloric, and sulphuric acids showed that thiourea in acid solution provide a good capability to strip silver from metal loaded tetramethylthiuram disulfide organic phase. Further study shows that the extent of extraction process depends on extractant concentration and also on the initial pH of the liquid photographic waste.
|Item Type:||Conference or Workshop Item (Paper)|
|Uncontrolled Keywords:||Disulfide, photographic waste, silver extraction, tetramethylthiuram|
|Subjects:||T Technology > T Technology (General)|
|Divisions:||Chemical and Natural Resources Engineering (Formerly known)|
|Deposited By:||Norhani Jusoh|
|Deposited On:||29 Jul 2008 06:17|
|Last Modified:||01 Jun 2010 15:37|
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