Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A kind of preparation method of high-purity nitric acid

A nitric acid, high-purity technology, applied in the direction of nitric acid, nitrogen oxides/oxyacids, etc., can solve the problems of high cost, cumbersome operation, unstable product quality, etc., and achieve low cost, simple operation process, and good removal effect. Effect

Active Publication Date: 2016-06-29
SHANGHAI CHEM REAGENT RES INST
View PDF5 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] The technical problem solved by the present invention is to provide a kind of preparation method of high-purity nitric acid, to overcome the deficiencies of complicated operation, high cost and unstable product quality in the prior art

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
  • A kind of preparation method of high-purity nitric acid
  • A kind of preparation method of high-purity nitric acid
  • A kind of preparation method of high-purity nitric acid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0030] 1. Preparation of melamine-formaldehyde-thiourea resin / polyacrylic acid resin composite film

[0031] Mix melamine, formaldehyde, thiourea, and polyacrylic acid resin at a molar ratio of 2:12:1:0.01, dissolve in deionized water, add NaOH solution to adjust pH=8.5-9.0, and react at 90°C for 2.5h. Then use HCl solution to adjust PH = 5, react at 120°C for 1.0h, wash and dry the obtained polycondensation product and mix it with polyacryl alcohol binder at a mass ratio of 5:3, at 85-90°C The composite membrane is made by sintering, and the obtained composite membrane is washed with high-purity nitric acid for use.

[0032] 2. Industrial grade nitric acid pretreatment

[0033] The silver nitrate and barium nitrate solution of 1-10wt% is prepared by ultrapure water and silver nitrate and barium nitrate respectively. Add 75-80wt% industrial grade nitric acid into the preprocessor 1, add 1-10wt% silver nitrate solution or barium nitrate solution dropwise under stirring at roo...

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
pore sizeaaaaaaaaaa
degree of polymerizationaaaaaaaaaa
Login to View More

Abstract

The invention discloses a preparation method of high-purity nitric acid, which uses industrial-grade nitric acid as a raw material, adds metal nitrate salt for reaction, performs membrane filtration through a microfiltration membrane to remove impurity anions in nitric acid, and passes through melamine-formaldehyde-thiourea resin / The polyacrylic resin composite material membrane is used for membrane filtration to remove impurity cations in nitric acid, and the filtrate is rectified, prepared with high-purity water, blown white, and filtered with a microfiltration membrane to obtain the target product. The content of the high-purity nitric acid obtained by the method of the present invention is 69-70wt%, the impurity metal ion is lower than 1ppb, and the dust particles greater than 0.5 micron are lower than 5 / ml, which meets the standard of SEMI C8, and the microfiltration membrane is used for membrane filtration, and the melamine -Formaldehyde-thiourea resin / polyacrylic acid resin composite membrane is used for membrane filtration, which can effectively remove impurity anions and cations in industrial-grade nitric acid, and the raw materials for making composite membranes can be reused, and the product has good purity, which is suitable for industrial production.

Description

technical field [0001] The invention relates to a method for preparing high-purity nitric acid, in particular to a method for preparing high-purity nitric acid meeting the SEMIC8 standard for chemical materials specified by the International Semiconductor Equipment and Materials Organization. Background technique [0002] Nitric acid is a strong oxidizing and corrosive acid. It is easily soluble in water. The dilute solution is colorless and transparent at room temperature. Industrial grade nitric acid is mainly produced by ammonia oxidation in industry, and is used to manufacture fertilizers, explosives, and nitrates. etc. Currently, the commercially available concentrated nitric acid is an azeotropic solution with a mass fraction of 69.2% (about 16mol / L). High-purity nitric acid is a kind of high-purity nitric acid aqueous solution, also known as electronic grade ultra-clean ultra-pure nitric acid. It is one of the important varieties of microelectronic chemical reagents. ...

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
Patent Type & Authority Patents(China)
IPC IPC(8): C01B21/46
Inventor 郑展超詹家荣蒋旭亮
Owner SHANGHAI CHEM REAGENT RES INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com