The present disclosure relates to a process for preparing a catalyst. The process comprises coating zeolite gel over the alumina support to obtain a chloride free zeolite gel coated alumina support, crystallizing the chloride free zeolite gel coated alumina support, washing, drying and calcining the crystallized zeolite coated alumina support to obtain a calcined crystallized chloride free zeolite coated alumina support, treating the calcined crystallized chloride free zeolite coated alumina support with ammonium nitrate to obtain sodium free support, washing, drying, and calcining the support to obtain a calcined chloride free zeolite coated alumina support, immersing the calcined chloride free zeolite coated alumina support in an active metal and a promoter metal solution mixture followed by stirring to obtain a metal coated chloride free zeolite coated alumina support, and drying and calcining the metal coated chloride free zeolite coated alumina support to obtain the catalyst.