Method for recycling epoxy resins and glass fibre from non-metal powder of waste printed circuit board

A technology for recycling epoxy resin and printed circuit boards, which is applied in plastic recycling, chemical recycling, recycling technology, etc., can solve the problems of limited amount of addition, pollution of resources, occupation of land resources, etc., and achieve full utilization of resources and high recovery rate high effect

Inactive Publication Date: 2009-04-15
SHANGHAI SECOND POLYTECHNIC UNIVERSITY
0 Cites 28 Cited by

AI-Extracted Technical Summary

Problems solved by technology

[0007] The present invention discloses a method for recovering epoxy resin and glass fiber from non-metallic powder of waste printed circuit board (PCB) under mild conditions. Incineration not only occupies valuable land resources, but also seriously wastes resources and pollutes the environment; using non-metallic powder as filler to p...
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

Method used

[0026] The present embodiment adopts low-concentration mineral acid, higher temperature and solid-to-liqui...
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

Abstract

The invention discloses a method for recycling epoxide resin and glass fiber from non-metal powder in waste printed circuit boards, comprising the following steps of: (1) pretreatment, and dust removal by washing; (2) removing residue metal: inorganic acid is used for removing the residue metal in the non-metal powder, and the obtained powder can be used directly after being filtrated; (3) preliminary decomposition: the processed non-metal powder is added into inorganic acid, the obtained mixture is heated for reaction and then filtrated; the filtrated solid is added into organic solvent, stirred and filtrated and the obtained solid is the glass fiber; and the organic solvent in the filtrate is evaporated so as to obtain the solid epoxide resin; and (4) secondary decomposition: the obtained solid epoxide resin is added into inorganic acid, and heated for reaction; and then the organic solvent is used for extraction and then is evaporated so as to obtain low molecular weight epoxide resin. The invention realizes green recycling of the non-metal powder of the waste printed circuit boards under the moderate condition and has high recovery rate, thus not only being capable of reducing the emission of pollutants but also leading the resource to be fully utilized.

Application Domain

Technology Topic

Examples

  • Experimental program(5)

Example Embodiment

[0023] Example 1
[0024] Add 150 mL of water to a 250 mL flask containing 30 g of waste PCB non-metal powder, stir for 4 to 5 minutes, pour off the water layer, and then wash with the same amount of water until the water layer is clear. Then add 150mL of 0.8mol/L sulfuric acid and heat at 55°C for 4 hours. The filtered solid is directly added to a 250mL flask, and then 300mL of 5mol/L nitric acid is added. After heating at 95°C for 35 hours, it is filtered and the filtrate is recovered and reused. After the solid was washed with water to neutrality, it was poured into a 250 mL round bottom flask, 150 mL of ethyl acetate was added, stirred, filtered, and washed with the same organic solvent until it was colorless to obtain glass fiber. The filtrate was evaporated to dryness to obtain a solid epoxy resin.
[0025] Add the solid epoxy resin obtained above into a 250mL round bottom flask, add 180mL of 4mol/L nitric acid/sulfuric acid, heat to 85°C with stirring, and react for 20 hours. After the reaction is completed, the water layer is extracted four times with ethyl acetate. , Combine the organic layers and spin dry the solvent to obtain a low molecular weight epoxy resin.
[0026] In this embodiment, a low concentration of inorganic acid is used, a higher temperature, solid-liquid ratio, and a longer reaction time are used. Although the concentration of the inorganic acid is low, the time is long.

Example Embodiment

[0027] Example 2
[0028] Add 150 mL of water to a 250 mL flask containing 30 g of waste PCB non-metal powder, stir for 4 to 5 minutes, pour off the water layer, and then wash with the same amount of water until the water layer is clear. Then add 300mL of 4mol/L sulfuric acid, heat at 35°C for 0.5 hours, directly add the filtered solid into a 250mL flask, add 90mL of 8mol/L nitric acid, heat at 75°C for 8 hours, filter, and recover the filtrate for reuse. After the solid was washed with water to neutrality, it was poured into a 250 mL round bottom flask, 100 mL ethyl acetate was added, stirred, filtered, and washed with the same organic solvent until it was colorless to obtain glass fiber. The filtrate was evaporated to dryness to obtain a solid epoxy resin.
[0029] Add the solid epoxy resin obtained above into a 250mL round bottom flask, add 7mol/L nitric acid/sulfuric acid 90mL, heat to 55°C with stirring, and react for 20 hours. After the reaction is completed, the water layer is extracted four times with ethyl acetate , Combine the organic layers and spin dry the solvent to obtain a low molecular weight epoxy resin.
[0030] In this embodiment, the higher concentration of the inorganic acid and the smaller amount of use reduce the solid-liquid ratio and the reaction time, but the acid concentration is too high, which is not conducive to operation.

Example Embodiment

[0031] Example 3
[0032] Add 150 mL of water to a 250 mL flask containing 30 g of waste PCB non-metal powder, stir for 4 to 5 minutes, pour off the water layer, and then wash with the same amount of water until the water layer is clear. Then add 150mL of 1mol/L nitric acid, heat at 40°C for 1.5 hours, directly add the filtered solid into a 250mL flask, add 100mL of 6mol/L nitric acid, heat at 85°C for 20 hours, filter, and recover the filtrate for reuse. After the solid was washed with water to neutrality, it was poured into a 250 mL round bottom flask, 100 mL ethyl acetate was added, stirred, filtered, and washed with the same organic solvent until it was colorless to obtain glass fiber. The filtrate was evaporated to dryness to obtain a solid epoxy resin.
[0033]Add the solid epoxy resin obtained above into a 250mL round bottom flask, add 5mol/L nitric acid/sulfuric acid 100mL, heat to 80°C with stirring, and react for 10 hours. After the reaction is completed, the water layer is extracted four times with ethyl acetate , Combine the organic layers and spin dry the solvent to obtain a low molecular weight epoxy resin.
[0034] In this embodiment, the addition amount, concentration, and reaction time of the inorganic acid are appropriate, and the obtained yield is relatively high, without causing waste of raw materials.
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

Description & Claims & Application Information

We can also present the details of the Description, Claims and Application information to help users get a comprehensive understanding of the technical details of the patent, such as background art, summary of invention, brief description of drawings, description of embodiments, and other original content. On the other hand, users can also determine the specific scope of protection of the technology through the list of claims; as well as understand the changes in the life cycle of the technology with the presentation of the patent timeline. Login to view more.
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

Similar technology patents

Classification and recommendation of technical efficacy words

  • Make full use of resources
  • High recovery rate

Beneficiation method of complex copper oxide ore

InactiveCN100998963AHigh recovery rateImprove concentrate gradeFlotationWet separationMaceralBeneficiation
Owner:陈铁

Method for recovering rare earth from waste rare earth luminescent material

InactiveCN102660688AHigh recovery rateProtect environmentGlass recyclingCerium oxides/hydroxidesRare-earth elementGlass matrix
Owner:UNIV OF SCI & TECH BEIJING
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