Dehalogenation of Pyrolysis Oils

This final section deals with the dehalogenation of pyrolysis oils from electronic scrap. In terms of using those materials for feedstock recycling, synthesis gas production or fossil fuel substitution, dehalogenation is strongly required. For feedstock recycling a 10 ppm 

A very different solution, and one suitable even for the selective production of HBr in the presence of chlorine, without any catalyst, is the treatment of the pyrolysis oils with molten polypropylene [13, 63, 56, 57, 59], Polypropylene acts within a temperature range of 310-350°C as a hydrogen donor. HBr is evolving from the brominated phenols and substituted phenols are formed in the case of the decomposition of flame retardants such as tetrabromobisphenol A (Figme 20.8). Together with HBr small brominated aliphatics are formed. Those can be converted to HBr together with all noncondensable compounds in a final oxidative cleaning. 

Meszaros, Advanced recycling technologies for plastics. In Conversion and Utilization of Waste Materials, M. R. Khan (ed.), Taylor Francis, Washington D.C., 1996. 

Meszaros, Advances in plastics recycling, thermal depolymerization of thermoplastic mixtures, ACS Symposium Series, 609, 170-182 (1995). 

Homung, Entwicklung eines Verfahrens zurfraktionierten thermischen Zersetzung von Kunststoffgemischen, Fortschritt-Berichte VDl, 3, 484, VDI Verlag, Dusseldorf, 1997. 

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