Abstract:
The purpose of this study is to apply chemical precipitation and electrochemical process to recover Tin from synthetic and real wastewater. This work is divided into three sections. The first section is to recover Tin by using chemical precipitation with Sodium Hydroxide and Sodium Sulfide. The second section is to recover Tin by electrochemical process with two types of electrode: graphite and stainless steel. Eight current levels are applied: 100, 150, 200, 500, 1000, 2000 and 400mA. The effect of electrode area and space are also investigated with 3.25x12 cm[superscript 2] and 6.5x12 cm[superscript 2] in area, and 5 cm and 10 cm in electrode space. Then, the optimum current, area of electrode, space of electrode and type of cathode electrode is applied with the real wastewater. The result of first section: With initial Tin concentration of 0.01 M, the optimum pH for precipitation by Sodium Hydroxide and Sodium Sulfide are 3 and 2, in which approximate 56% and 80% of Tin recovered The result of second section shows that 100% of Tin can be recovered from synthetic wastewater by electrochemical process at these following optimum conditions: current at 500mA, area of electrode of 6.5x12 cm[superscript 2] , space of electrode at 5 cm and the stainless steel cathode with the operation time of 6hours. The result of last section shows that 87% of Tin can be recovered from the real wastewater by electrochemical process. It is found that cost of electrochemical process is more expensive than chemical precipitation, but electrochemical process provides a pure Tin metal, which is also less toxic to the environment.