Bulk and supported catalysts are prepared from an aqueous slurry containing a catalytically active material and a binder. The slurry is either coated onto a support and dried to form a porous, high surface area phase containing the catalytically active material, or reduced to a paste-like consistency, molded and dried to form a bulk catalyst. The processes and catalysts may be employed in various catalytic chemical processes to achieve high effectiveness factor of the catalytically active material while achieving a lower pressure drop.