SINTESIS HIJAU Mg-Al-LDH DAN ADSORPSI ISOTERMAL HIDROGEN PADA PRODUK; GREEN SYNTHESIS OF Mg-Al-LDH AND ITS HYDROGEN ISOTHERMAL ADSORPTION
Adriyani, Lies Wuryanita, Sri Juari Santosa
2015 | Disertasi | FMIPAMg-Al Layered Double Hydroxide (Mg-Al-LDH) was successfully synthesized using mechanochemical approach by manual grinding Mg(NO3)2·6H2O, Al(NO3)3·9H2O, and NaOH. Grinding using mortar and pastle in mol ratio (R) Mg:Al variation, time variations, and drying method. Synthesized powder was characterized using X-ray difractogram (XRD), infrared spectrometer (FT-IR) and N2 adsorption-desorption (BET). The ability of Mg-Al-LDH as hydrogen adsorbing material was analyzed using isothermal adsorption volumetric method, introducing hydrogen gas stream into the Mg-Al-LDH at various pressures at room temperature (25oC). The results demonstrated that optimum synthesis of Mg-Al-LDH was obtained at a ratio of Mg:Al 3:1 with 60 minutes grinding time. Increase in temperature (80°C oven) affected crystallinity and surface area. Mg-Al-LDH ability to adsorb hydrogen increased with pressure. LDH-Ov had better hydrogen adsorption than the that of LDH-Des. The best approach of isothermal adsorption model equations for Mg-Al-LDH isothermal hydrogen adsorption was Langmuir with capacity of adsorption LDH-Des 3,95 10-4 mol g-1 and 4,63 10-4 mol g-1 in LDH-Ov. Energy of adsorption show that adsorption process occur by physical adsorption.
Kata Kunci : layered double hydroxide; mechanochemical; mortar; hydrogen adsorption
