Method for producing potassium dihydrogen phosphate with double decomposition method

A technology of potassium dihydrogen phosphate and metathesis, which is applied in the field of production of potassium dihydrogen phosphate by metathesis, can solve the problems of low concentration of by-product hydrochloric acid, low recovery value, prolonging reaction time, etc., so as to increase the concentration of by-product hydrochloric acid, improve The effect of recycling value and reducing production energy consumption

Active Publication Date: 2010-10-13
GUIZHOU CHANHEN CHEM CO LTD
View PDF4 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although this method solves the strong corrosion problem of hydrochloric acid and phosphoric acid mixed acid, it has the following two disadvantages: ①The core reactor adopts graphite reactor. Large diameter ratio, small effective volume, difficult to achieve mass production
② The hydrogen chloride gas produced by potassium chloride and phosphoric acid escapes from the liquid phase by stirring, the escape efficiency is low, and the conversion time of potassium chloride is long, reaching 1.5 to 4 hours, which seriously restricts the reaction rate and makes it difficult to realize large-scale industrial production
Compared with CN1324760A, although this method i

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for producing potassium dihydrogen phosphate with double decomposition method
  • Method for producing potassium dihydrogen phosphate with double decomposition method
  • Method for producing potassium dihydrogen phosphate with double decomposition method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] with P 2 O 5 %=30 phosphoric acid and potassium chloride powder with a particle size of 180 μm to 250 μm are reacted at a molar ratio of P / Cl=1.8 / 1, first make potassium chloride and phosphoric acid fully mixed, and the mixture is injected into the spray tower for reaction, and then The temperature of the tower is 400 °C, the temperature of the outlet is 180 °C, and the temperature of the metathesis reaction is controlled at about 200 °C. 2 O 5 The concentration of %=25 is hydrolyzed at a temperature of 110 ° C, then potassium hydroxide is added to adjust the pH value of the hydrolysis solution to 4.3~4.5, cooling and crystallization to obtain potassium dihydrogen phosphate product, and the crystallization mother liquor is returned to the hydrolysis tank for recycling. The hydrogen chloride gas generated in the spraying process is washed and absorbed with a 25% w / w potassium hydroxide solution to obtain potassium chloride.

[0035] Reaction under this condition, the ...

Embodiment 2

[0039] with P 2 O 5 %=40 phosphoric acid and potassium chloride powder with a particle size of 75 μm to 96 μm are reacted at a molar ratio of P / Cl=1.6 / 1, first make potassium chloride and phosphoric acid fully mixed, and the mixture is injected into the spray tower for reaction, and then The temperature of the tower is 500 °C, the temperature of the outlet is 200 °C, and the temperature of the metathesis reaction is controlled at about 260 °C. 2 O 5 After the concentration of %=35 is hydrolyzed at a temperature of 90 DEG C, potassium hydroxide is added to adjust the pH value of the hydrolysis solution to 4.3~4.7, cooling and crystallization to obtain potassium dihydrogen phosphate product, and the crystallization mother liquor is returned to the pH adjustment tank for recycling. Hydrochloric acid is obtained by washing and absorbing the hydrogen chloride gas generated during the spraying process with water.

[0040] Reaction under this condition, the material conversion rat...

Embodiment 3

[0044] with P 2 O 5 %=40 phosphoric acid and potassium chloride powder with a particle size of 150 μm to 180 μm are reacted with the molar ratio of P / Cl=1.4 / 1. First, the potassium chloride and phosphoric acid are fully mixed, and the mixture is injected into the spray tower for reaction. The temperature of the tower is 500 °C, the temperature of the outlet is 200 °C, and the temperature of the metathesis reaction is controlled at about 260 °C. 2 O5 After the concentration of %=35 is hydrolyzed at a temperature of 90 DEG C, potassium hydroxide is added to adjust the pH value of the hydrolysis solution to 4.3~4.7, cooling and crystallization to obtain potassium dihydrogen phosphate product, and the crystallization mother liquor is returned to the pH adjustment tank for recycling. Hydrochloric acid is obtained by washing and absorbing the hydrogen chloride gas generated during the spraying process with water.

[0045] Reaction under this condition, the material conversion rate...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Granularityaaaaaaaaaa
Granularityaaaaaaaaaa
Granularityaaaaaaaaaa
Login to view more

Abstract

The invention relates to a method for producing potassium dihydrogen phosphates, in particular to a method for producing potassium dihydrogen phosphate with a double decomposition method. The invention is characterized by further improving the quality of a potassium dihydrogen phosphate product and enhancing the concentration of byproduct hydrochloric acid on the basis of the work of the previous period. The method comprises the following steps of: mixing potassium chloride powder with a phosphoric acid solution, carrying out double decomposition reaction in a spray tower, dissipating hydrogen chloride gas generated by the reaction along with hot air for preparing hydrochloric acid or chlorate; and hydrolyzing, neutralizing and crystallizing double decomposition reaction materials after the hydrogen chloride gas is dissipated to prepare a potassium dihydrogen phosphate product. By adopting the method, it is unnecessary to dissolve potassium chloride into phosphoric acid, it is only necessary for adequately mixing the potassium chloride solid powder with phosphoric acid, therefore, the reaction time is shortened, the production energy consumption is reduced, the production efficiency is improved, and the conversion rate is higher up to more than 99%; meanwhile, the concentration of by-product hydrochloric acid can reach above 25%, and can reach as high as 33%, and the recycling value is greater.

Description

technical field [0001] The invention relates to a method for producing potassium dihydrogen phosphate, in particular to a method for producing potassium dihydrogen phosphate by a metathesis method. Background technique [0002] There are many production methods of potassium dihydrogen phosphate, mainly neutralization method, extraction method, ion exchange method, metathesis method, direct method, crystallization method and electrolysis method. In my country, the neutralization method is mostly used in the production process, and the extraction method, metathesis method, ion exchange method, and direct method have not yet been industrialized. Although the neutralization method is simple, the potassium hydroxide is expensive, the production cost is high, and the added value is low; other methods such as potassium chloride and phosphoric acid metathesis low-temperature extraction method have serious loss of extractant, high price, and serious environmental pollution; phosphate...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C01B25/30
Inventor 李进李光明邹建程相桂薛河南
Owner GUIZHOU CHANHEN CHEM CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap