Sodium stannate preparation from stannic oxide by a novel soda roasting–leaching process

The Formation of Sodium Stannate from Mineral Cassiterite by the Alkaline Decomposition Process with Sodium Carbonate (Na2CO3)

“…2 shows that sodium stannat (Na 2 SnO 3 ) phase was found at cassiterite decomposition products. This result of phase identification same with the results of Zhang, Y [4] and Bunnakkha, C [6] experiments. Fig.…”

“…The similar tendensies were found by Zhang, Y et.all [4] during decomposition of cassiterite by concentrated sodium carbonate (Na 2 CO 3 ). He found that when the mole ratio of Na 2 CO 3 were increased rapidly until it tends to be balanced at the Na 2 CO 3 to cassiterite mole ratio higher than 1.50.…”

“…The temperature of the carbolyte furnace was controlled by a programmable temperature controller. The reaction of cassiterite with sodium carbonate (Na 2 CO 3 ) forms sodium stanate (Na 2 SnO 3 ) and could be described as follows [4] …”

“…in sodium stannat and will dissolve in the water when done heating and crystallization, from the research results obtained leaching efficiency of 85.6% and the product had a purity of 95.8% SnO 2 , with optimal conditions the decomposition temperature of 875 °C, 15% CO gas content, the decomposition time 15 minutes, mole ratio Na 2 CO 3 /cassiterite 3: 2, leaching temperature of 40 °C, leaching time of 60 minutes, stirring speed of 300 rpm and the ratio L/S 4 cm 3 /g [4]. c) The process of extracting tin from tin concentrate using low levels of HCl 150 g/L, 2 hours, 35 °C which is able to separate the iron up to 99.4%, but the process of decomposition continued with a mixture of 55% Na 2 CO 3 , 12% NaOH, 30% residue leaching and 3% of coal at a temperature of 870 °C.…”

“…The alternative process that applied in this research is extracted through decomposition with sodium carbonate to produce sodium stannat, where sodium stannat can be dissolved in water [4][5][6] to obtain filtrate enriched with tin (Sn). The mole ratio of Na 2 CO 3 to cassiterite, temperature and reaction time are critical parameters for the sodium stannat phase formation of the yield value of the final product as a tin dioxide (SnO 2 ).…”