Allyl 2,4,6-tribromophenyl ether (TBP-AE) is a flame retardant that is added to plastics to improve their fire resistance. This kind of additive is hazardous to both human health and the environment. As any other BFRs, TBP-AE resists photo-degradation in the environment and hence materials laden with TBP-AE are to be dibrominated to avoid environmental pollution. Mechanochemical degradation of TBP-AE is a promising approach with potential industrial applications since it does not require high temperatures nor it generates any secondary pollutants. A planetary ball milling simulation experiment was designed to study TBP-AE’s mechanochemical debromination. To report products from the mechanochemical process, a variety of characterization techniques were used. The characterization methods included gas chromatography-mass spectrometry (GC–MS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX). The effects of various co-milling reagent types, co-milling reagent concentrations with raw material, time, and revolution speed on mechanochemical debromination efficiency have been thoroughly investigated. The Fe/Al2O3 mixture entails the highest debromination efficiency of 23%. However, when using a Fe/Al2O3 mixture, neither the reagent concentration nor the revolution speed influenced the debromination efficiency. In case of using only Al2O3, the next viable reagent, it was revealed that while increasing the revolution, speed improved debromination efficiency to a certain point, and increasing it any further left the debromination efficiency unchanged. In addition, the results showed that an equal mass ratio of TBP-AE to Al2O3 promoted degradation more than an increase in the ratio of Al2O3 to TBP-AE. The addition of ABS polymer largely inhibits the reaction between Al2O3 and TBP-AE, which hindered alumina’s ability to capture organic bromine, causing a significant decrease in the debromination efficiency when model of waste printed circuit board (WPCB) is considered.
- Ball milling
- Mechanochemical debromination
ASJC Scopus subject areas
- Environmental Chemistry
- Health, Toxicology and Mutagenesis