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TOLEDO (SPAIN)CHEMICAL RECYCLING OF ELECTRONIC DEVICES COMPOSED OF
THERMOSETTING RESIN AND INORGANIC COMPOUNDS
H. Ebina, H. Tagaya
Yamagata university, Graduate School of Science and Engineering
e-mail: tmd58609@st.yamagata-u.ac.jp

Abstract
It is not easy to recover organic and inorganic compounds from waste electronic devices because valuable materials ofthem were covered and protected by thermosetting resin such as phenol resin. In this study, we have carried out thedecomposition reaction of thermosetting resin in supercritical liquid such as high-temperature water and high-temperature
alcohol.

Keywords: electronic device, IC package, supercritical water, supercritical alcohol, thermosetting resin

1. Introduction
Recently, it is a big social trouble to increase waste
matter such as plastic materials and electronic device, todecrease final disposal site. Effective recycling processof waste compounds is desired. Especially, thermosetting
resin can not be applied to material recycling likethermoplastic resin by heating or remolding. It isnecessary to replace reclamation and direct burning as
polite resource management.
In the other sense, supercritical water has been received
more and more attention as a medium for chemical
reaction, because supercritical water has low dielectric
constant and behaves similar to organic solvents having
high thermal stability [1,2].
We have already confirmed that waste plastics such as
phenol resin decompose into their monomericcompounds in sub and supercritical water.
In this study, to obtain information on decomposition
reaction of IC package contained in electronic device torecover organic and inorganic materials by using super
critical liquid only.

the case of shocked IC package after the reaction for 2hin water 2.0mL , it can be broken easily. It was difficult tobreak the raw and direct heating IC package by shocking
the same level power. It was considered that the impact
resistance of the IC package reduced.Organic part of IC
package was resolved. Furthermore, it is confirmed thatphysical proportion like used high-temperature alcohol by
CO2 addition in water 2.0mL at 350ºC [3]. However,chemical change such as increase decomposition
product can’t be observed.
(a)

(b)

(c)

(d)

2. Materials and Methods
Decomposition reactions in high-temperature water werecarried out with IC package by using 10mL tubing bomb
reactor. The reaction was carried out at prescribedtemperature and time. After decomposition reaction, solid
residuum was dried, and analyzed by SEM and EDS.
The liquid product was extracted with organic solventsand identified by GC/MS and quantified by GC with aflame ionization detector (FID).

3. Results and Discussion
Fig.1 shows the raw material, and decomposition
products of IC package after the reaction. Compared todirect heating IC package and decomposition IC package
in water, there is no change in appearance. However, ininteriores libro.indd 121

Fig.1. Photographs of (a) raw IC package,
decomposition products of IC package after the reaction
for 2h (b) direct heating at 400ºC. (c) in water 2.0mL at
350ºC, (d) in water 2.0mL adding CO2 0.5g at 350ºC.
When ether extraction, extraction ratio improved thatphysical changed IC package irrigate and recover by
diethylether. GC/MS chromatograms shows that bis(2ethylhexyl) phthalate used as plasticizer was recovered
as shown in Fig.2.

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6th International Symposium on Feedstock Recycling of Polymeric Materials

References
Intensity[arb.units][1] H. Tagaya and T.Aita. Liquid phase decomposition ofwaste plastic. Technology for Feedstock Recycling ofPlastic Wastes (2005) 222–237.
[2] T. Sako (Ed.), Chorintai Ryuta, Agene shofusha(2001).
[3] T. Sugeno and H. Tagaya. Recycling of Polymeric
Waste Materials. FSRJ Symposium proceedings 13thChiba (2010) 39–40.

515

102025

Time[min]Fig.2. GC/MS chromatograms of the decomposition
reaction products of IC package for 2h (a) in water 2.0mL
at 350ºC and (b) in water 2.0mL adding CO2 0.5g at350ºC.
SEM image and EDS patterns suggest the presence ofC, Cu, O, Si, Sn and S on metal surface. Fig.3 shows
EDS pattern. After the reaction, Sn was removed and Cu
and Si increased. It is considered that coated Sn
detached, Cu exposed by high-temperature watertreatment.

Counts[x1.E+3]

(a)

SnCu
SiCOCu(b)S02

46810keVFig.3. EDS pattern of (a) raw material, (b) decomposition
products of IC package after the reaction for 4h in water
3.0mL at 350ºC.

4. Conclusions
IC package composed of thermosetting resin andinorganic material solubilized in high-temperature water.
By adding CO2, confirmed physical change on condition
that lower temperature compared with only water.
However, chemical change can’t be observed.

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