锯酸领制锯酸钠的研究.

The method of separation of chromate from high alkali medium by barium salt to get the intermediate product of barium chromate was proposed, and through the acid dissolution reduction method to get chromium hydroxide. Then, using the oxidability and acidity of hydrogen peroxide, it takes sodium hydroxide as a sodium source and accurately regulates the reaction conditions. The chromium hydroxide is directly oxidized to sodium chromate without by-products. The effects of reaction temperature, reaction time, liquid-solid ratio, stirring speed, quantity of hydrogen peroxide, and chromium alkali molar ratio have been studied, the reaction process was optimized by response surface method. The results showed that the optimal reaction alkali chromium molar ratio 2.15∶1（stoichiometric ratio）, liquid-solid ratio 3.9∶1 mL/g, theoretical multiple of hydrogen peroxide 1.86, temperature conditions were 88 ℃ and agitation speed of 300 r/min. Under this condition, the chromium oxidation rate can reach 99.56% for reaction 90 min. [ABSTRACT FROM AUTHOR]