1. METHOD VALIDATION FOR THE DETERMINATION OF EXCHANGEABLE CATIONS IN NATURAL ZEOLITES USING INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROMETRY. Authors: MARIN SENILA, OANA CADAR, MARIA-ALEXANDRA HOAGHIA, ZAMFIRA DINCA, LACRIMIOARA SENILA, IOAN ASCHILEAN, CECILIA ROMAN.2. ACTIVATED NATURAL ZEOLITES FOR PETROLEUM HYDROCARBONS ADSORPTION. Authors: MARIA-ALEXANDRA HOAGHIA, IOAN ASCHILEAN, VANDA BABALAU-FUSS, ANCA BECZE, OANA CADAR, CECILIA ROMAN, MARIUS ROMAN, MARIN SENILA, ENIKO KOVACS.