Patent ID: 9157133
Filing Date: 2015-10-13
Classification: C01G,C22B

Abstract:
1. A method for producing alkali metal dichromate from carbon ferrochrome as the raw material through a hydrothermal process, the method comprising the steps of (1) formulating the raw material carbon ferrochrome together with an alkali and water into an initial reaction liquid, in which the actual addition-to-theoretical-requirement ratio of the alkali in oxidizing chromium in the carbon ferrochome to form alkali metal chromate is 55% to 80%; (2) adding the initial reaction liquid formulated in step (1) into a reaction kettle, charging an oxidizing gas into the reaction kettle, and allowing a reaction to proceed for 0.5 to 3 h at a temperature of 150° C. to 370° C. and a pressure of 2 MPa to 24 MPa, wherein CO (3) subjecting the reaction products from the reaction in step (2) to solid-liquid separation, cooling the resultant filtrate to a temperature of −12° C. to −20° C. to precipitate crystals, and separating the solution therefrom which is an alkali metal dichromate solution.