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The influence of the molar ratio H2O/SiO2 in the synthesis directly from Bangka Belitung’s Kaolin has been studied by performing synthesis of ZSM-5 with a variation of the molar ratio H2O/SiO2 is different at 15, 25, 30, and 35. Weighing 3.980 g Bangka’s kaolin are added other material so obtained molar composition 10Na2O: 120SiO2: 2Al2O3: 1800-4200H2O, and 1% of silicalite seed, subsequent hydrothermal process of 175°C for 24 hours. The result of solids was analyzed by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) and SEM EDX to the analyzed morphology of ZSM-5 crystal. The synthesis of ZSM-5 was directly optimum with molar ratio H2O/SiO2 of 30 having the highest cristallinity and largest crystal size of 59.44% and 3.795 µm, respectively.

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ZIF-67 and MCM-41/ZIF-67 composites were successfully synthesized with water solvent at room temperature. The amounts of MCM-41 added during synthesis were varied at 2.5, 5 and 10 (%w/w) toward the amount of ZIF-67, and the obtained solids were denoted as MC (2.5)/ZIF-67, MC (5)/ZIF-67, and MC (10)/ ZIF-67, respectively. The X-ray diffraction (XRD) patterns of ZIF-67 and the composites showed characteristic peaks at 2θ of 7.32, 10.36, 12.69, 14.66, and 16.40°, similar to that of reported ZIF-67. The Fourier transform infra-red (FT-IR) spectra of all solids showed absorption bands at the same wavenumbers as reported for ZIF-67. The results of surface morphology analysis using scanning electron microscope (SEM) have shown that ZIF-67 and the composites have a cube shape, which is characteristic for the ZIF-67 standard. N 2 adsorption-desorption data showed that the specific surface area of ZIF-67 and MC (5)/ZIF-67 were 1079.2 and 1011.2 m 2 /g, respectively, lower than that of MC (10)/ZIF-67 (1250.6 m 2 /g). However, results of thermal gravimetric analysis (TGA) showed that the thermal stability of MC (10)/ZIF-67 reached 357°C, higher than that of ZIF-67 (325°C). Performance of the composites as adsorbent of methyl orange (MO) in aqueous solution showed that the MC (5)/ZIF-67 had the highest adsorption capacity of 167.635 mg/g, and followed the pseudosecond-order adsorption kinetics and Langmuir isothermal adsorption.