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| | Methanedisulfonic acid dipotassium salt Basic information |
| | Methanedisulfonic acid dipotassium salt Chemical Properties |
| density | 1.622[at 20℃] | | Water Solubility | 34.438g/L at 20℃ | | LogP | -1.83 at 20℃ |
| | Methanedisulfonic acid dipotassium salt Usage And Synthesis |
| Uses | Methanedisulfonic acid dipotassium salt is widely used in electroplating process. As the main component of chromium plating additives, it can significantly improve the corrosion of the plating solution on the anode plate, resulting in a brighter surface, higher hardness of the coating, more microcracks and higher corrosion resistance. | | Flammability and Explosibility | Not classified | | Synthesis | Methanedisulfonic acid dipotassium salt is synthesised using 1,1-dibromomethane as a raw material by chemical reaction. The specific synthesis steps are as follows:
Raw Materials: CH2Br2: 140 g/0.8 mol K2SO3 (45% in water) 600 g/1.7 mol [(C4H9)4N]Br: 6 g KI: 0.8 g; A mixture of 600 g K2SO3-solution (45% in water), 6 g of [(C4H9)4N]Br and 0.8 g KI in 400 ml of water, was heated to 70° C. Within a period of 16 hours, 140 g of CH2Br2 were transferred under the surface of the reaction mixture. During the addition of CH2Br2, the pressure in the reactor was determined with 1007-1008 mbar. Afterwards the reaction mixture was heated up to 90° C. After a total reaction time of 24 h, K2[CH2(SO3)2] started to precipitate. After 72 hours at 90° C., complete conversion of CH2Br2 to [CH2(SO3)2]2- has been achieved. The reaction mixture was cooled down to 20° C. The precipitated K2[CH2(SO3)2] was isolated by suction filtration and washed three times with 100 ml of water. The product was dried 6 hours at 80° C. under atmospheric pressure. Yield: 175 g (86.7%) Composition: Assay: 99.7% (Titration) Br-: 111 ppm (Ion-chromatography) SO32-:<50 ppm (Ion-chromatography) SO42-: 54 ppm (Ion-chromatography); Purification by Recrystallization 175 g of K2[CH2(SO3)2] were suspended in 600 ml of water. The suspension was heated to about 100° C. At a pressure of about 40 mbar, 362 ml of water were evaporated out of the mixture. The remaining suspension was cooled down to 20° C. The precipitated K2[CH2(SO3)2] was isolated by suction filtration and dried 6 h at 80° C. under atmospheric pressure. Yield: 165.4 g (94.5%) Overall yield: 81.9% Composition: Assay: 99.8% (Titration) Br-: <10 ppm (potentiometric titration) SO32-: <50 ppm (Ion-chromatography) SO42-: <50 ppm (Ion-chromatography).
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| | Methanedisulfonic acid dipotassium salt Preparation Products And Raw materials |
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