THE OPTIMIZATION OF PRODUCTION ZEOLITE Y CATALYST FROM RHA BY RESPONSE SURFACE METHODOLOGY - Anggoro, Didi Dwi; Department of Chemical Engineering, Faculty of Engineering, University of Diponegoro Jl. Prof. Soedarto, SH, Tembalang, Semarang, Indonesia, 50239, Tlp.:62-24-7460058, Fax.: 62-24-76480675 (Dept. of Chemical Engineering, Diponegoro University, 2012)