Studies on Bromination and Evaporation of Zinc Oxide during Thermal Treatment with TBBPA

Abstract

Thermodynamic considerations indicate that base metal oxides such as ZnO, PbO, Cu2O, etc. should easily react with HBr, the main gaseous product from the thermal decomposition of tetrabromobisphenol A (TBBPA), to form low boiling point metallic bromides suitable for volatile separation. In this work a differential scanning calorimeter and laboratory-scale furnace was used to investigate the scope and conditions for the bromination of ZnO by the thermal decomposition of TBBPA. The formed solid, condensed, and gaseous products were analyzed by X-ray diffraction analysis, electron probe microanalysis, inductively coupled plasma analysis, ion chromatography, and gas chromatography coupled with mass spectrometry. The results obtained in this study indicate that the bromination of ZnO occurred at 272 degrees C (DSC) and above 290 degrees C (furnace) with an effectiveness of 41, 64, and 81% dependent on the experimental conditions. Volatilization of the formed ZnBr2 began at 340 degrees C and had a 45% yield at 650 degrees C. This yield corresponded to 28-36% of the original zinc content in the mixture under the present experimental conditions.

Studies on bromination and evaporation of antimony oxide during thermal treatment of tetrabromobisphenol A (TBBPA)

“…The evidence of char formation during the thermal decomposition of pure TBBPA was confirmed in many studies [8][9][10]25]. However, it was also found that the presence of some halide metals (SbCl 3 , ZnBr 2 ) [5,28] and (SbOCl) [28] may enhance char formation.…”

“…For these materials, hydrobromic acid (HBr) must be released as a product of decomposition of BFR plastics during pyrolysis [4]. We have suggested in a previous paper, the possibility of a volatile separation of metallic compounds such as zinc oxide (ZnO) in the waste by the HBr released from the tetrabromobisphenol A (TBBPA) decomposition [5].…”

Characteristics of exhaust gas, liquid products, and residues of printed circuit boards using the pyrolysis process

“…In addition, Vasile et al (2007) used computer scrap, i.e., PCBs, casings, and keyboards, to produce oil and high aromatic fraction content in liquid oil. Furthermore, it is possible that bromobisphenol A and brominated bromobisphenol A (2.3-10%) were found in the liquid product because they did not completely decompose during the pyrolysis process (Barontini et al 2004b;Barontini et al 2005;Grabda et al 2009). But the bromobisphenol A and brominated bromobisphenol A species contents in liquid product were low or at trace levels in GC-MS spectra of liquid product in this study.…”

Thermal degradation study of tetrabromobisphenol A under the presence metal oxide: Comparison of bromine fixation ability

“…A thermodynamic consideration suggests that base metal oxides including ZnO, PbO and Cu 2 O react readily with HBr originating from degradation of TBBA [13]. Recent study by Grabda et al showed that the bromination of zinc took place in the simultaneous heat treatment of the mixture of TBBA and ZnO [14]. In the present work we have examined the influence of variety of metal oxides, namely ZnO, Fe 2 O 3 , La 2 O 3 , CuO and CaO, on the thermal degradation of TBBA.…”