Production process and production device for electroplating grade potassium pyrophosphate

Abstract

The invention discloses a production process for electroplating grade potassium pyrophosphate. The production process comprises the following steps of taking 85 percent phosphoric acid and 48 percent potassium hydroxide as raw materials; performing a neutralization reaction in a neutralization reaction kettle, and controlling the pH value of slurry to be 8.5 to 9.5; filtering the slurry by a fine filter, then feeding the slurry into a slurry storage tank, and keeping the temperature of the slurry in the storage tank to be 70 to 90DEG C; feeding the slurry in the storage tank into an evaporation and concentration device for concentrating; then feeding a concentrated solution into a continuous crystallization device for performing continuous crystallization operation; after centrifugal treatment, returning filtrate to the evaporation and concentration device and enabling a potassium dihydrogen thophosphate crystal to enter vacuum drying equipment for performing vacuum drying treatment; conveying a dried material into an indirect heating dynamic polymerization furnace and polymerizing to form potassium pyrophosphate; cooling, breaking, screening and packaging to obtain a finished product. Compared with electroplating grade potassium pyrophosphate on the market, the electroplating grade potassium pyrophosphate obtained by the invention has the advantages of higher dissolution speed, higher purity, more excellent complexing power and better Hull cell test results.

Description

technical field [0001] The invention belongs to the technical field of electroplating grade potassium pyrophosphate production, and in particular relates to a high-quality electroplating grade potassium pyrophosphate production system and process. Background technique [0002] Potassium pyrophosphate is mainly used in cyanide-free electroplating, replacing sodium cyanide as a complexing agent for electroplating. It is also used as a pretreatment and pyrophosphate plating solution for electroplating. It can also be used as an additive to configure laundry detergent components, metal surface detergents and bottle cleaner components, and various cleaning agents. It can also be used as a clay dispersant in the ceramic industry, a dispersant and buffer for pigments and dyes. In the bleaching and dyeing industry, it is used to remove a small amount of ferric ions in water to improve the quality of bleaching and dyeing. It is used as emulsifier, tissue modifier, chelating agent,...

AI Technical Summary

Problems solved by technology

[0003] At present, domestic electroplating grade potassium pyrophosphate basically adopts one-step or two-step production process, and the production site has a lot of dust, and the bulk density of the product after atomization is small, about 0.3g / mL~0.5g / mL, and the dust recovery rate Low, and most of them use clean energy such as natural gas or hydrogen as fuel, which greatly increases the production cost. The content of potassium pyrophosphate product obtained by this production process is relatively low, the content is less than 99%, and the complexation index is relatively small, approximately 2.6mL In the range of ~2.9mL, the effect of the Hull cell test is poor, such as poor brightness of the coating, excessive foggy area, more spots and perforations, etc. The impurities in the product are relatively high, especially metal elements such as sodium calcium magnesium aluminum iron Impurities

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