Pyrolysis appears to be an emerging option allowing recovery of useful products from wastes of electric and electronic equipment (WEEE) because of the high value of potentially accessible products such as precious metals or coke (in the residue), fuel and chemicals (pyrolysis oil and gases). However, contamination of oil by harmful compounds remains a severe issue and has a strong impact on material recycling and thermal treatment: Bromine-containing phenols are classic examples of harmful compounds emitted during pyrolytic recycling of printed circuit boards, and their dehalogenation is an area of continuing scientific interest. Pyrolysis of 2,4-dibromophenol (DBP) with high density polyethylene (HDPE), low density polyethylene (LDPE), polybutadiene (PBD), polystyrene (PS), polyamide 6 (PA-6), polyamide 6,6 (PA-6,6) and polyacrylonitrile (PAN) at 290–370 ◦C for 20 min results in the successive transformation of DBP to monobromophenols and further to phenol and HBr, together with small amounts of alkylphenols, depending on the reaction temperature and reactivity of polymers. The formation of PBDDs and PBDFs is strongly retarded despite of the structure of DBP, which favours their development. The rate of hydrodebromination decreased in the series LDPE >HDPE> PBD > PS≈PA-6 > PA-6,6 > PAN. The hydrodebromination process transforms the polymers studied in the highly polyaromatized char. The formation of the pyrolysis products is in favour of a radical hydrodebromination mechanism.

Thermal hydrodehalogenation of 2,4-dibromophenol by polymeric materials

LUDA DI CORTEMIGLIA, Maria Paola;
2011

Abstract

Pyrolysis appears to be an emerging option allowing recovery of useful products from wastes of electric and electronic equipment (WEEE) because of the high value of potentially accessible products such as precious metals or coke (in the residue), fuel and chemicals (pyrolysis oil and gases). However, contamination of oil by harmful compounds remains a severe issue and has a strong impact on material recycling and thermal treatment: Bromine-containing phenols are classic examples of harmful compounds emitted during pyrolytic recycling of printed circuit boards, and their dehalogenation is an area of continuing scientific interest. Pyrolysis of 2,4-dibromophenol (DBP) with high density polyethylene (HDPE), low density polyethylene (LDPE), polybutadiene (PBD), polystyrene (PS), polyamide 6 (PA-6), polyamide 6,6 (PA-6,6) and polyacrylonitrile (PAN) at 290–370 ◦C for 20 min results in the successive transformation of DBP to monobromophenols and further to phenol and HBr, together with small amounts of alkylphenols, depending on the reaction temperature and reactivity of polymers. The formation of PBDDs and PBDFs is strongly retarded despite of the structure of DBP, which favours their development. The rate of hydrodebromination decreased in the series LDPE >HDPE> PBD > PS≈PA-6 > PA-6,6 > PAN. The hydrodebromination process transforms the polymers studied in the highly polyaromatized char. The formation of the pyrolysis products is in favour of a radical hydrodebromination mechanism.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
90
63
71
Pyrolysis; Dehydrobromination; Brominated flame retardants; Polymer waste; Recycling
Maria Paola Luda; A.I. Balabanovich
File in questo prodotto:
File Dimensione Formato  
post print da depositare.pdf

embargo fino al 01/01/2013

Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 361.26 kB
Formato Adobe PDF
361.26 kB Adobe PDF Visualizza/Apri
JAAP 11 90 63-71.pdf

non disponibili

Tipo di file: PDF EDITORIALE
Dimensione 665.44 kB
Formato Adobe PDF
665.44 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2318/85534
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 7
social impact