STUDY OF SYNTHESIS OF TIN SULFATE BY ELECTROLYTIC METHOD

• Main Author: BUDI PRATAMA (NIM : 12512057), RISTIA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/30545
• Institution: Institut Teknologi Bandung

Tin (Sn) is one of non-ferrous metals which is widely used in human daily-life. Tin is used commonly as solder, tinplate and organotin compounds. Tin is also made into tin derivative products of tin compounds based, either organic inorganic compounds. One of such product is tin sulphate. Tin sulfate is utilized for preparing electrolyte material for tin electrolysis process, namely electrorefining and electroplating. In this research, the efforts of making tin sulfate compounds by electrolysis of pure tin anode in sufuric acid solution in order to generate Sn2+ and SO42- ions which subsequently forms tin-sulfate compound at saturated condition was made. Sn2+ ions are obtained from dissolving the pure lead metal anode through the electrolysis process. The experiment was conducted by using pure tin plate sample received from tin smelting and refining of PT. Timah (Persero) Tbk. in Muntok, Bangka Island. <br /> <br /> <br /> <br /> <br /> A series of electrolysis experiments at room temperature (25 oC) has been performed by using electrolytic cell with cathode and anode configuration facing each other vertically. The anode was placed on the bottom of the cell, while the cathode was located at the top of the cell in order to avoid tin metal deposition at the surface of the cathode. The electrolysis experiments were conducted to study the effect of current density, the concentration of sulfuric acid, and the use of PVC insulation barrier in the electrolytic cell on the dissolution of Sn. The electrolysis test was stopped when Sn metal deposition at the cathode surface occurs. The dissolved Sn concentrations as a function of time from various electrolysis conditions were periodically measured by Atomic Absorption Spectrophotometry (AAS). The solution resuted from the electrolysis experiment using PVC barrier at current density of 350 A/m2 and sulfuric acid 1M for 27h was crystallized by heating the solution at temperature of 150oC to synthesize SnSO4 crystalline powder. The powder was then analyzed by X-Ray Diffraction (XRD) method to identify the dominant compound in powder and X-Ray Fluorescence (XRF) to determine the chemical composition of the powder. <br /> <br /> <br /> <br /> <br /> The experimental result shows that the highest dissolved Sn concentration (prior to deposition of Sn metal) of 37.12 g/L was obtained by electrolysis test with PVC barrier for 27h with sulfuric acid concentration of 1M and current density of 350 A/m2. The use of insulation barrier in the electrolysis cell increased the Sn concentration that can be achieved before the Sn metal deposition takes place. The condition of saturated dissolved Sn on the vicinity of the anode surface led to anode passivation which was indicated by a significant increase of cell voltage and oxygen gas evolution from the anode surface. The incease of anode potential above the equilibriu potential of Sn2+/Sn4+ promoted oxidation of Sn2+ to Sn4+. XRD analysis of crystallized powder revealed that the dominant compound was stannic sulfate (Sn (SO4)2). <br />