A process for producing a percarbonate without the addition of a chloride salting out agent in which the dissolution step restricts the sodium carbonate to 60-90% of its saturated concentration at 35C

A continuos process for the manufacture of sodium percarbonate in which hydrogen peroxide, sodium carbonate and an aqueous medium are introduced into a reaction vessel in which the hydrogen peroxide and sodium carbonate react. The resultant sodium percarbonate precipitates out of solution, is separated from the mother liquor and recovered as product. At least a fraction of the mother liquor, which inherently contains a residual amount of sodium carbonate in aqueous form is recycled to the reaction vessel. Particulate sodium carbonate is continually added to the process so that the ratio of Hydrogen peroxide to sodium carbonate in the reaction vessel is within the range of more that 0.7:1 and less than 1.3:1. The temperature of the reaction is maintained within the range of 10 to 25oC thereby continuously forming and precipitating sodium percarbonate. The invention provides a process intended to be conducted without addition of chloride salting-out agent in which the dissolution step is controlled to restrict the sodium carbonate concentration to below 95 % of its saturated concentration at a temperature preferably controlled to at most 35 °C. In some embodiments, at least a fraction of the mother liquor introduced into the dissolution tank is obtained by extraction from the reaction vessel. In other embodiments a fraction of the sodium percarbonate is introduced in solution in the mother liquor and a fraction is introduced in particulate form directly into the reaction vessel. Large particle sodium percarbonate is provided which has a 7 day aged heat emission at 40 °C of not more than 3mW/g measured in a microcalorimeter over 16 hours that is lower than the heat emission from conventionally produced sodium percarbonate employing a chloride salting-out agent.