Non-ammonia molybdenum precipitation method for sodium-modifying vanadium-rich liquor

Abstract

The invention relates to a non-ammonia molybdenum precipitation method for sodium-modifying vanadium-rich liquor. The non-ammonia molybdenum precipitation method comprises the following steps: 1) regulating the pH value of the sodium-modifying vanadium-rich liquor with sulfuric acid, and adding calcium chloride and an aluminum sulfate solution to purify, remove silicon, remove phosphine and filter; 2) regulating the pH value of the obtained purified filtrate with the sulfuric acid, adding the sulfuric acid, introducing CO2 under a stirring condition, adding certain polymer polyvanadic acid asseed crystal, heating to a temperature of 90 DEG C or higher, and preserving the heat for 1-2 hours until molybdenum precipitation is complete, and filtering; 3) adding an acidic ammonium sulfate solution into obtained filter residues, introducing CO2 under the stirring condition, and heating up to a boiling point for sodium removal and filtration, adding lime to treat and filter by supplementingammonium sulfate into filtrate to circulate by certain times, returning filtrate to a fine vanadium burning furnace, and spraying and absorbing ammonia gas released by fine vanadium burning, and recycling produced ammonium sulfate for sodium removal of polymer polyvanadic acid; and 4) washing the filter residues with a sulfuric acid aqueous solution and clear water to further produce vanadium pentoxide. The non-ammonia molybdenum precipitation method has the beneficial effects of solving emission of ammonia nitrogen wastewater from the source, and being environmentally friendly.

Description

technical field [0001] The invention belongs to the field of hydrometallurgy, and in particular relates to a method for vanadium-free precipitation of vanadium-rich liquid in sodium. Background technique [0002] At present, the recovery of vanadium in sodium-rich vanadium-rich liquid is mainly to add ammonium chloride to precipitate vanadium to produce ammonium metavanadate, or use sulfuric acid to adjust the pH value to about 2.0, add ammonium sulfate to heat and precipitate vanadium to produce ammonium polyvanadate. Due to the low product content of hydrolysis vanadium precipitation, the red cake obtained by hydrolysis vanadium precipitation is used in industry, and the alkali-soluble ammonium salt precipitation vanadium is refined to obtain qualified vanadium products. The above vanadium precipitation processes need to add ammonia salt to obtain qualified vanadium products , produces a large amount of ammonia-nitrogen wastewater, the vanadium precipitation mother liquor ...

AI Technical Summary

Problems solved by technology

Due to the low product content of hydrolysis vanadium precipitation, the red cake obtained by hydrolysis vanadium precipitation is used in industry, and the alkali-soluble ammonium salt precipitation vanadium is refined to obtain qualified vanadium products. The above vanadium precipitation processes need to add ammonia salt to obtain qualified vanadium products , produces a large amount of ammonia-nitrogen wastewater, the vanadium precipitation mother liquor cannot be recycled, and needs to be neutralized by adding lime for ammonia distillation and deammoniation to reuse the process, which increases the investment in infrastructure equipment, and the vanadium in the vanadium precipitation mother liquor cannot be recovered, resulting in the loss of vanadium. The cost of sinking vanadium is high, but once there is a great environmental hazard

Images