Method for preparing zirconium sulfate tetrahydrate with zirconium carbonate production wastewater

Abstract

The invention discloses a method for preparing zirconium sulfate tetrahydrate with zirconium carbonate production wastewater. The method comprises the technical steps of: (1) adjusting a pH (Potential of Hydrogen) value of the zirconium carbonate production wastewater with dilute alkali, performing sedimentation, (2) pumping the wastewater into a plate-and-frame filter press for press filtration, purging with compressed air after the press filtration, removing a plate, obtaining zirconium hydroxide, (3) dissolving zirconium hydroxide in sulfuric acid or zirconium sulfate tetrahydrate mother liquor at a mass-volume ratio of 1:(1-3), heating to 50-60 DEG C to completely dissolve zirconium acyl hydroxide, filtering off mechanical impurities, and (4) adding concentrated sulfuric acid into filtrate to adjust a system sulfuric acid concentration to 50-70%, naturally cooling to 40 DEG C for crystallization, centrifuging, and obtaining zirconium sulfate tetrahydrate. The method is simple in technology, prepares zirconium sulfate tetrahydrate with the zirconium carbonate production wastewater, and prevents the zirconium carbonate production wastewater from influencing an environment; obtained zirconium sulfate tetrahydrate is high in purity and is up to a national first grade standard; since the zirconium sulfate tetrahydrate mother liquor is recycled, the production cost is lowered effectively; and environmental resources are saved.

Description

technical field [0001] The invention belongs to the technical field of zirconium carbonate production wastewater treatment, in particular to a method for preparing zirconium sulfate tetrahydrate from zirconium carbonate production wastewater. Background technique [0002] At present, the domestic production of basic zirconium carbonate mainly adopts a two-step process, the steps are: zirconium oxychloride → basic zirconium sulfate → adding carbonate → zirconium carbonate. A large amount of industrial wastewater is produced during washing of basic zirconium carbonate, exceeding 15 tons / ton of product, and the mass content of ZrO2 is greater than 4g / L, which must be recycled. At present, some domestic enterprises neutralize the waste water with the waste alkali water produced in the production of zirconium oxychloride, and add water purifiers for sedimentation treatment. The resulting waste residue contains ZrO 2 It contains about 5% and contains a large amount of impuritie...

AI Technical Summary

Problems solved by technology

The first method has long process, low metal recovery rate, unstable product quality and high production cost

Due to the use of hydrochloric acid in the second method, the equipment is severely corroded and the operating environment is poor

Due to low-acid leaching and high-acid hydrolysis, the metal recovery rate is low, and the product contains high titanium content.

The third one uses zirconium oxychloride to produce zirconium sulfate, although the quality is very good, but the cost is very high

This process is a solid phase reaction, such as mass production, the reaction is difficult to control, and the resulting product has high impurity content and poor consistency

Moreover, the reaction is an exothermic reaction, a large batch reaction, which will cause local overheating and dehydration of zirconium sulfate tetrahydrate, which will affect the solubility of zirconium sulfate tetrahydrate

Therefore, this method usually cannot realize industrial production

Images