Pyrolysis characteristics of integrated circuit boards at various particle sizes and temperatures

Chiang, Hung‐Lung; Lin, Kun-You; Lai, Mei-Hsiu; Chen, Ting-Chien; Ma, Sen-Yi

doi:10.1016/j.jhazmat.2007.03.064

Cited by 83 publications

(36 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The main decomposition occurred at 300 °C-600 °C with an accompanying conversion of about 90%. The main thermal degradation temperature in this paper were a little high when compared to the work of Chen et al [19] and Chiang et al [31] which could be caused by high heating rates and different compositions. Thus, the general weight loss in the WPCBs can be characterized by the following stages: the weight of the sample barely changed when its temperature remained below 300 °C; thereafter the sample underwent a rapid weight loss in the temperature range of 300 °C-600 °C.…”

Section: Conventional Pyrolysis Of Wpcbs Using Tgacontrasting

confidence: 53%

Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating

et al. 2012

View full text Add to dashboard Cite

This paper describes a kinetic study of the decomposition of waste printed circuit boards (WPCB) under conventional and microwave-induced pyrolysis conditions. We discuss the heating rates and the influence of the pyrolysis on the thermal decomposition kinetics of WPCB. We find that the thermal degradation of WPCB in a controlled conventional thermogravimetric analyzer (TGA) occurred in the temperature range of 300 °C-600 °C, where the main pyrolysis of organic matter takes place along with an expulsion of volumetric volatiles. The corresponding activation energy is decreased from 267 kJ/mol to 168 kJ/mol with increased heating rates from 20 °C/min to 50 °C/min. Similarly, the process of microwave-induced pyrolysis of WPCB material manifests in only one stage, judging by experiments with a microwave power of 700 W. Here, the activation energy is determined to be only 49 kJ/mol, much lower than that found in a conventional TGA subject to a similar heating rate. The low activation energy found in microwave-induced pyrolysis suggests that the adoption of microwave technology for the disposal of WPCB material and even for waste electronic and electrical equipment (WEEE) could be an attractive option.

show abstract

Section: Conventional Pyrolysis Of Wpcbs Using Tgacontrasting

confidence: 53%

Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating

et al. 2012

View full text Add to dashboard Cite

show abstract

“…It is possible to describe the pyrolysis behaviour of PCB scraps under different conditions by different pyrolysis mechanis ms [13], [19][20][21][22]. The deco mposition rate of the pyrolysis process depends on an arbitrary reaction order.…”

Section: Pyrolysis Kineticsmentioning

confidence: 99%

Pyrolysis of Printed Circuit Boards

Mankhand¹,

Singh²,

Gupta³

et al. 2013

IJMEE

View full text Add to dashboard Cite

Printed Circuit Board (PCB) is an essential co mponent of almost all electrical and electron ic equip ments. The rapid growth of the use of such equipments has contributed enormously to the generation of large quantity of waste PCBs. The WPCBs not only contain valuable metals but also a large variety of hazardous materials. Conventional treat ments of such WPCBs have their o wn limitations. By pyrolysis of WPCBs, it is not only possible to obtain the organic part o f it as a fuel or useful chemical but can make further processing to recover metals much easier and efficient. In the present work, a kinetic study on the low temperature pyrolysis of WPCBs using a thermogravimet ric analyser has been attempted. The TG analysis was conducted in nitrogen and air at mospheres in the temperature range of 200-600℃ at a heating rate of 40℃ /min. The kinetic expressions for both the environments were determined and the activation energies were found to be 110.7 and 90.2 kJ/ mo l for n itrogen and air, respectively. The effect of thermal pre-t reatment on the subsequent copper leaching in nitric acid for untreated, pyrolysed and air-burned PCB was also studied. Copper recoveries fro m these samples were 30.4%, 92.5% and 96.2%, respectively indicating the importance of thermal pre-treat ment in leaching of the metal content.

show abstract

“…Serious pollution can be generated if PCBs are not properly disposed of since the flame retardants therein may cause the formation of halogenated dioxin-like compounds, such as polybrominated dibenzo-p-dioxins (PBDDs) or polybrominated dibenzofurans (PBDFs) [5,6]. Meanwhile, WPCBs is attracting more and more attention due to the valuable materials it contains [7,8]. Therefore, the recycling of WPCBs has a great practical significance for sustainable development of the human living environment and resources recycling.…”

Section: Introductionmentioning

confidence: 99%

Degradation of brominated epoxy resin and metal recovery from waste printed circuit boards through batch sub/supercritical water treatments

Xing

Zhang

2013

Chemical Engineering Journal

135

View full text Add to dashboard Cite

h i g h l i g h t s" This work provides an efficient and green approach for waste printed circuit boards recycling. " Debromination of brominated epoxy resins and recycling of metals was simultaneously achieved. " Brominated epoxy resins can be completely decomposed by sub/SCW treatments. " Glass fibers and copper foils in WPCBs were liberated and could be easily separated by crushing after sub/SCW treatment. a r t i c l e i n f o b s t r a c tWaste printed circuit boards (WPCBs) contain high amount of brominated flame retardants and heavy metals which may bring a series of environmental and health problems. In the present study, an effective and benign process using sub-and supercritical water (sub/SCW) to simultaneously degrade brominated epoxy resin and recover metals from WPCBs was developed. Experiments were performed in a batch-type reactor with temperatures ranging from 200 to 400°C, water adding amounts from 10 to 40 ml and holding times from 30 to 240 min. The results showed that brominated epoxy resins (BERs) could be quickly and efficiently decomposed under sub/SCW condition. The debromination rate was 97.8% by controlling the temperature, water adding amount and holding time at 400°C, 40 ml and 120 min, respectively. Most of the bromine was changed into HBr and around 97.7% was enriched in water. Meanwhile, bromine-free oil was obtained of which the main compositions were phenol (58.5%) and 4-(1-methylethyl)-phenol (21.7%). After the sub/SCW treatments, the glass fibers and copper foils in the residue can be easily liberated and recovered respectively. The copper recovery rate reached 98.11% in the purities of 96.74% (grain size >2.0 mm) and 92.74% (0.147-2.0 mm). This study provides an efficient and green approach for WPCBs recycling.

show abstract

Pyrolysis characteristics of integrated circuit boards at various particle sizes and temperatures

Cited by 83 publications

References 23 publications

Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating

Kinetic Study of the Pyrolysis of Waste Printed Circuit Boards Subject to Conventional and Microwave Heating

Pyrolysis of Printed Circuit Boards

Degradation of brominated epoxy resin and metal recovery from waste printed circuit boards through batch sub/supercritical water treatments

Contact Info

Product

Resources

About