Surface analysis of carbon black waste materials from tire residues

X-ray photoelectron spectroscopy (XPS) has been used to obtain surface chemical state information on two carbon black waste materials in terms of the surface element distribution/concentration and chemical structure. Small amounts of sulfur in the form of CS, were detected on the surface (less than 1.7 mass %). C-H/C-C was the major carbon functional component on the surface of carbon black samples but other functional forms of carbon were also present such as C=O and C-O. The surface of the carbon black obtained from a hydropyrolysis process was highly oxidized primarily in the form of carbon based oxygen groups. On the other hand, surface oxygen atoms on the surface of the carbon black obtained from a pyrolysis process in the absence of H-2 were in the form of both metal oxides and carbon based oxygen groups. (C) 1999 Elsevier Science B.V. All rights reserved.