Porous benzene phenol polymer and carbon were synthesized in the presence of Pluronic P123 as template. Sulfonation of the porous structures yielded solids with sulfonic acid groups. The compositions of the solid acids were characterized using elemental analysis and thermogravimetric analysis methods. Their pore structures were investigated by physical adsorption of nitrogen. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy were used to characterize surface functional groups. Carbonization of porous benzene phenol polymer at evaluated temperatures transferred the polymer to carbon as proven by X-ray diffraction and transmission electron microscope techniques. The catalytic properties of the solid acids were evaluated using esterification of methanol with acetic acid. Results showed that the catalytic activity for the sulfonated polymer increased with the increase in sulfonation temperature. Sulfonic acid groups on the polymer framework were observed to be more stable than those on the carbon framework. (C) 2010 Elsevier B. V. All rights reserved.