| 摘要 |
The invention relates to a process for the production of compact, coarse sodium percarbonate which comprises reacting hydrogen peroxide at 10 to 20 DEG C, with an input solution containing sodium carbonate and saturated with sodium percarbonate in the presence of 100 to 200 g of sodium chloride per litre of solution, at least one active oxygen stabiliser and from 0.1 to 1.9 g of sodium hexametaphosphate per litre of solution, the ratio of soda to sodium hexametaphosphate in the input solution being from 65:1 to 500:1, hydrogen peroxide being added to the soda input solution or suspension in a quantity which is substantially equivalent to the sodium carbonate dissolved and/or suspended in the input solution at a temperature maintained at substantially one and the same level throughout the entire precipitation process, subsequently reducing the over-saturation of dissolved sodium percarbonate formed by precipitation of the sodium percarbonate during and for up to 60 minutes after addition of the hydrogen peroxide, and separating off and drying the salt obtained. Optionally the mother liquor accumulating is returned to the working stage for the soda input solution. |
