Sodium hypophosphite monohydrate CAS# 10039-56-2

1. one-step method refers to the use of yellow phosphorus and one of the following reactants to react and directly produce sodium hypophosphite method: (l) NaOH, (2) alkaline earth metal hydroxide and NaOH mixture (mainly NaOH), (3) alkaline earth metal hydroxide and Na2CO3 mixture. For example, yellow phosphorus in an inert atmosphere and a mixture of lime milk and Na2CO3 solution heated reaction, the release of phosphine and hydrogen, the reaction is over, filtered to separate the reactants, the filtrate is a solution of sodium hypophosphite, the filter cake consists of unreacted lime and calcium phosphate, calcium phosphate, etc… The filtrate is filtered through CO2 to remove the dissolved calcium hydroxide, and the filtrate is concentrated under reduced pressure to obtain NaH2PO2-H2O. The one-step process is simple and can produce a more concentrated solution with lower energy consumption and higher product yield. The one-step process has become the main method of industrial production of sodium hypophosphite

2. Two-step method (complex decomposition method) two-step method is to first use yellow phosphorus in an inert atmosphere and alkaline earth metal hydroxide reaction, or with alkaline earth metal hydroxide and NaOH mixture reaction (mainly alkaline earth metal hydride) to make alkaline earth metal hypophosphate, and then make alkaline earth metal hypophosphate and sodium carbonate for complex decomposition to make hypophosphite. Sodium phosphate. Nitrogen is commonly used as an inert gas. The most commonly used alkaline earth metal hydroxide is Ca(OH)2. Barium hydroxide and magnesium hydroxide can also be used, but the cost of raw materials is higher. The two-step process is longer, more than one filtration, the washing process, and the solubility of calcium hypophosphite is lower than sodium hypophosphite, to reduce the amount of residual hypophosphite in the filter cake, we must increase the amount of washing water, and the washing solution and filtrate combined, so that the solution obtained is very dilute, evaporation and concentration of a lot of energy consumption.

3.Used as analytical reagents, also used in clinical tests.

4.Reducing agent, activator, molecular weight regulator, and heat stabilizer; arsenic and iodate reagent.