The in situ synthesis of binderless ferrierite (FER) (ZSM-35) coatings on 300 si cordierite honeycomb support was explored. To this end, the influence of the type of template on the FER coating formation was studied, as well as the effect of the feed-to-surface ratio (mol(Si)/m(sup)(2)), the silica-to-alumina ratio of the synthesis mixture and the development of the FER coating as a function of time. Crystalline coatings were obtained that were firmly attached to the support. Scanning electron microscopy (SEM) micrographs showed FER crystals of rather diverse morphology as a function of synthesis conditions. The formation of FER was confirmed by X-ray diffraction.