Detergents are cleaning agents that consist of a complex formulation such as surfactants, builders, bleaching, fillers and other additives. Detergent builder that commonly used is sodium tripolyphosphate (STPP) that are unfriendly environmentally. One of the detergent builders that is more environmentally friendly is zeolite. Therefore, in the present work, zeolite was synthesized using hydrothermal method by varying the temperature and characterised its detergent builder properties. Zeolite was synthesized by mixing sodium silicate (Na2SiO3) and sodium aluminate NaAl(OH)4 with the presence of NaOH. Firstly, a mixture of sodium silicate and sodium aluminate formed sol and gradually become gel. After that, the gel had been treated by hydothermal for 7 hours at different temperatures: 500C, 1000C and 1500C. Several characteristic techniques such as FTIR and XRD were applied to identify functional group and the crystal structure, respectively. Furthermore, the detergent builder properties were characterised using cation exchange capacity (CEC) and detergency test. The result showed that zeolite synthesized at 100 0C gave better washing capability than others
