Nearly complete removal of zeolite particles and Fe/Co catalysts from raw single-walled carbon nanotubes (SWNTs) produced by chemical vapor deposition was achieved by oxidation of raw material at 240degreesC or 340degreesC and treatment with 1% aqueous solution of hydrofluoric acid. The yields of SWNTs were estimated to be approximate to95% and the purities of SWNTs thus obtained were more than 95%, as characterized by thermo-gravimetric analysis. Raman spectra of the purified SWNTs were essentially identical with those of the corresponding raw samples. The raw and purified SWNTs were also characterized by EDX spectroscopy and transmission electron microscopy. (C) 2004 Elsevier B.V. All rights reserved.