Liberation of metal clads of waste printed circuit boards by removal of halogenated epoxy resin substrate using dimethylacetamide

Delamination mechanism study of large size waste printed circuit boards by using dimethylacetamide

“…Further, the delamination of different size PCBs has also been investigated in this work under optimized parameters (PCB:DMA ratio of 3:10 (wt/vol)) reported by Verma et al (2017b). Up to the author's knowledge, the mechanism of the interaction of the solvent DMA with the BER of WPCBs has not been previously reported.…”

“…The reaction of solvent with PCBs results in the dissolution of BER, acting as a binder to hold the various layers of PCBs together (Verma et al, 2017b). The resin is formed by curing of di-glycidyl ether of bromine substituted Bisphenol A (BPA) with suitable hardener (Luda et al, 2007).…”

“…Later, interloping of the solvent inside the layer of PCBs occurs, and it results in dissolution of BER at slower rates. This is because of the through holes, which are copper coated holes drilled through the cross-section of PCBs (Verma et al, 2017b). Since smaller size PCBs the number of through holes are less and thus, DMA interlopes quickly into laminas of smaller PCBs.…”

“…Among the various solvents, the organic solvent found most pronounced application because of their low cost, easy operation, regeneration and negligible effluent generation. Solvent dimethylsulfoxide (Zhu et al, 2013b), N,N-dimethyl pyrrolidone (Wath et al, 2015), dimethylformamide (Verma et al, 2017a(Verma et al, , 2016 and dimethylacetamide (DMA) (Verma et al, 2017b) have registered successful liberation of metal clad of PCBs. A comparative assessment of reported solvents has been shown in Table 1.…”

“…Previous studies reported that under conditions viz. PCB:DMA ratio of 3:10 (wt/vol), temperature 433 K; the DMA result in the most efficient dissolution of the BER of PCBs, relatively (Verma et al, 2017a(Verma et al, , 2017b. Further, it has also been reported that the spent DMA is entirely recyclable without negligible loss in its efficiency and the dissolved solute is the BER that is recovered as residue, later.…”