A resource recovery method for circuit board tin stripping waste liquid

A resource recovery and circuit board technology, applied in chemical instruments and methods, tin compounds, copper sulfate and other directions, can solve the problems of human and environmental hazards, high impurity content, low separation efficiency, etc. The effect of emission and consumption saving

Active Publication Date: 2017-10-13
GUANGZHOU KECHENG ENVIRONMENTAL PROTECTION TECH
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Wherein the neutralization method is relatively mature and widely used, and brings economic and environmental benefits to a certain extent, but the neutralization method in the prior art generally has the following two problems at present: the one is that the pH is higher when precipitating tin ions, Usually between 1.0 and 2.0, this requires the use of a large amount of lye, and the tin ions precipitated under this pH condition often contain some other metal ions, the impurity content is high, and the purity of tin ions is low; The solution is usually adjusted to a certain pH value, and then several other metals are co-precipitated, which leads to the fact that several metals still need to be separated during subsequent recycling, and the separation efficiency is low; in addition, the existing neutralization There are still a large amount of nitrate ions, polycyclic and heterocyclic organic substances and polymers in the waste liquid treated by the method, which is very harmful to human beings and the environment; therefore, it is still necessary to find a simple operation, high separation efficiency, A low-cost method for recycling and treating waste liquid from tin stripping of circuit boards

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 resource recovery method for circuit board tin stripping waste liquid
  • A resource recovery method for circuit board tin stripping waste liquid
  • A resource recovery method for circuit board tin stripping waste liquid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] (1) Take 1L of tin stripping waste liquid whose composition is shown in Table 1, add 3000mL of sodium hydroxide solution with a molar concentration of hydroxide radicals of 0.25mol / L to it, adjust the pH to 0.5, stir for 30min, and perform solid-liquid Separate to obtain the filter cake A1 with components as shown in Table 2 and the filtrate B1 with components as shown in Table 3;

[0026] (2) Take the filtrate B1, add 100 mL of sodium hydroxide solution with a molar concentration of 2.78 mol / L to it, adjust the pH value to 1.5, and carry out solid-liquid separation to obtain the filter cake A2 with the components shown in Table 4 and the components shown in Table 4 Filtrate B2 shown in 5;

[0027] (3) Take the filtrate B2, add 20 mL of sodium hydroxide solution with a molar concentration of 6.00 mol / L to it, adjust the pH value to 6.0, and carry out solid-liquid separation to obtain the filter cake A3 with the components shown in Table 6 and the components shown in Tab...

Embodiment 2

[0031] (1) Take 1L of tin stripping waste liquid whose composition is shown in Table 1, add 320mL of sodium hydroxide solution with a molar concentration of hydroxide radicals of 3.20mol / L to it, adjust the pH to 0.8, stir for 30min, and perform solid-liquid Separate to obtain the filter cake A1 with components as shown in Table 2 and the filtrate B1 with components as shown in Table 3;

[0032] (2) Take the filtrate B1, add 70 mL of sodium bicarbonate solution with a hydroxide molar concentration of 4.35 mol / L to it, adjust the pH value to 2.5, carry out solid-liquid separation, and obtain the filter cake A2 whose composition is shown in Table 4 With composition as the filtrate B2 shown in table 5;

[0033] (3) Take the filtrate B2, add 17mL of sodium carbonate solution with a molar concentration of hydroxide of 7.94mol / L to it, adjust the pH value to 7.0, and carry out solid-liquid separation to obtain the filter cake A3 and Components are filtrate B3 as shown in table 7; ...

Embodiment 3

[0037] (1) Take 1 L of the tin stripping waste liquid whose composition is shown in Table 1, add 165 mL of sodium hydroxide solution with a molar concentration of hydroxide radicals of 6.00 mol / L to it, adjust the pH to 1.0, stir for 30 minutes, and perform solid-liquid separation , to obtain the filter cake A1 with composition as shown in table 2 and the filtrate B1 with composition as shown in table 3;

[0038] (2) Take the filtrate B1, add 55 mL of sodium bicarbonate solution with a hydroxide molar concentration of 6.00 mol / L to it, adjust the pH value to 4.0, and perform solid-liquid separation to obtain the filter cake A2 with the components shown in Table 4 With composition as the filtrate B2 shown in table 5;

[0039](3) Take the filtrate B2, add 15 mL of sodium carbonate solution with a hydroxide molar concentration of 10.0 mol / L to it, adjust the pH value to 8.0, and carry out solid-liquid separation to obtain the filter cake A3 and Components are filtrate B3 as show...

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

No PUM Login to view more

Abstract

The invention relates to a recycling method of a circuit board solder stripping waste liquid, which comprises the following steps: S1: dropwisely adding an alkaline solution with the hydroxy molar concentration of 0.25-6.00 mol / L into the circuit board solder stripping waste liquid to regulate the pH value of the system to 0.5-1.0, and carrying out solid-liquid separation to obtain precipitated tin; S2: continuing adding the alkaline solution into the filtrate obtained in the step S1 to regulate the pH value of the system to 1.5-4.0, and carrying out solid-liquid separation to obtain precipitated iron; and S3: continuing adding the alkaline solution into the filtrate obtained in the step S2 to regulate the pH value of the system to 6.0-8.0, and carrying out solid-liquid separation to obtain precipitated copper. The method provided by the invention implements step-by-step recycling on heavy metals in the solder stripping waste liquid, and implements zero discharge of the heavy metal waste liquid. The method provided by the invention is more environment-friendly, and has higher popularization and application value.

Description

technical field [0001] The invention relates to a method for recovering heavy metals in waste tin stripping liquid, in particular to a resource recovery method for circuit board tin stripping waste liquid. Background technique [0002] Tin stripping waste liquid is a kind of acid wastewater produced in the production process of printed circuit boards, which contains a large amount of nitric acid, tin, iron, copper and other metal ions, as well as a small amount of polycyclic and heterocyclic organic compounds and polymers, etc., which are directly discharged After entering the environment, it is very harmful to humans and the environment. The existing technologies for treating waste liquid from tin stripping of circuit boards mainly include neutralization method, distillation method, electrolysis method, membrane separation method and solvent extraction method. Wherein the neutralization method is relatively mature and widely used, and brings economic and environmental bene...

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): C02F9/04C01G19/00C01G3/10C01D9/04C01G49/00C01G3/00
CPCC01D9/04C01G3/00C01G3/10C01G19/00C01G49/00C01P2006/80C01P2006/82
Inventor 吴阳东郭云霄刘杨査正炯王永成
Owner GUANGZHOU KECHENG ENVIRONMENTAL PROTECTION TECH
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