Method for preparing potassium sulfate

Abstract

The invention discloses a method for preparing potassium sulfate. The method comprises the following steps: 1) mixing and stirring potassium mixed salt mine, potassium chloride, sodium sulfate and a solvent to obtain a solid-liquid mixture; 2) regulating the solid-liquid volume ratio of the solid-liquid mixture to 1:(3-5), adding a flotation medicament for flotation, and then filtering and separating obtained flotation foam to obtain soft leonite and first mother liquor; 3) mixing the obtained soft leonite and potassium chloride according to the mass ratio of (1.6-2.0): (0.8-1.2), adding a washing solution to basically clean Na<+> in the mixture, and then filtering and separating to obtain a solid phase and second mother liquor; and 4) adding the solid phase in the step 3) into fresh water according to the solid-water mass ratio of (1.0-1.5):1, converting for 1-1.5h at the temperature of 60-70 DEG C, and then cooling, filtering and separating to obtain a potassium sulfate product and third mother liquor. According to the method disclosed by the invention, a byproduct of a salt lake, namely sodium sulfate is fully utilized, fresh water resources are saved in the production process, the production period is shortened, the production efficiency is improved and the production cost is further reduced.

Description

technical field [0001] The invention belongs to the field of salt lake chemistry, and in particular relates to a method for preparing potassium sulfate by utilizing salt lake resources. Background technique [0002] The production method of potassium sulfate at present mainly contains: (1) sulfuric acid method produces potassium sulfate; (2) double decomposition method produces potassium sulfate; (3) seawater or brine produces potassium sulfate; (4) solid potassium ore extraction method produces potassium sulfate; (5) Other specific or developing methods for obtaining potassium sulfate. [0003] Wherein the sulfuric acid method produces the method for potassium sulfate including the Mannheim method: [0004] The Mannheim method is a process for producing potassium sulfate from sulfuric acid and potassium chloride. Its production method is to use potassium chloride and concentrated sulfuric acid to react step by step in the Mannheim furnace. First, the reaction generates po...

AI Technical Summary

Problems solved by technology

The membrane separation method uses sulfuric acid and potassium chloride as raw materials, and uses a membrane distillation reactor to produce potassium sulfate. It has the advantages of low energy consumption and no chlorine in the product. However, because many exchange membranes need to be imported, the production cost is greatly increased. Increase

[0031] It is worth pointing out that the extraction of potassium sulfate by the above-mentioned processes is mostly aimed at special raw materials or specific resources, and most of the research work remains in the experimental stage, and further innovations in large-scale industrial production are still awaited.

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