The ammonia method was used to prepare cobalt phyllosilicates catalysts. Simultaneous thermogravimetry analysis and its derivative-differential scanning calorimetry (TGA-DTG-DSC) comparison studies on Co(NO3)(2).6H(2)O, SiO2 aerosil 200 precursor, after being treated with the ammonia method, and on the final synthesized catalyst, indicated that the first step during the synthesis process is the cobalt aqua-complex formation that interacts with the silica aerosil 200 forming Co-phyllosilicate. Temperature-programmed reduction studies (TPR) show at least two phases for such catalysts. One, is a lower-temperature phase (603 K), corresponding to free cobalt aqua-complex, and the other a cobalt phyllosilicate phase at higher temperature (1123 K). Such phases can be separated by washing and filtration and were identified by Fourier transform infrared (FTIR) spectroscopy. The capability of the sample (high solubility) being separated into two phases excluded the possibility of having a cobalt hydroxide as the low-temperature phase. The catalyst is active for carbon monoxide hydrogenation and very selective to methanol and ethanol formation in the proportion 2:1, similar to that found for the two metal phases in the catalyst by TPR. (C) 2004 Elsevier B.V. All rights reserved.