PENGARUH WAKTU AGING DAN RASIO MOL Si/Al TERHADAP SINTESIS MCM-41 PADA TEMPERATUR KAMAR

ISTI YUNITA, Dr. Sutarno, M.Si.

2011 | Tesis | S2 Ilmu Kimia

Pengaruh waktu aging dan rasio mol Si/Al terhadap sintesis MCM-41 pada temperatur kamar telah dipelajari. Sampel MCM-41 disintesis menggunakan bahan dasar natrium silikat dan surfaktan cetiltrimetilamonium bromida (CTAB). Struktur MCM-41 hasil sintesis pada temperatur kamar dibandingkan dengan MCM-41 hasil sintesis dengan metode hidrotermal. MCM-41 sebelum dan sesudah kalsinasi digunakan untuk adsorpsi fosfat dan metilen biru dengan variasi pH, waktu kontak dan konsentrasi adsorbat. Pengaruh waktu aging dan rasio mol Si/Al pada struktur dikarakterisasi dengan menggunakan metode difraksi sinar-X, spektroskopi inframerah dan adsorpsi desorpsi gas nitrogen. Jumlah konsentrasi fosfat dan metilen biru dianalisis dengan menggunakan metode spektroskopi sinar tampak. Hasil penelitian menunjukkan bahwa kondisi optimum sintesis MCM-41 pada temperatur kamar diperoleh pada waktu aging 48 jam dan rasio molar Si/Al = 25. Kondisi optimum adsorpsi fosfat pada MCM-41 dan Al-MCM-41 sebelum kalsinasi dicapai pada pH 5,5 dan waktu kontak 60 menit, dengan hasil kapasitas adsorpsi berturut-turut sebesar 50,27 mg.g-1 dan 49,95 mg.g-1. Kemampuan adsorpsi metilen biru pada Al-MCM-41 sesudah kalsinasi lebih tinggi dari kemampuan adsorpsi MCM-41 setelah kalsinasi

Effect of aging time and mole ratio of Si/Al on the synthesis of MCM-41 at room temperature has been studied. MCM-41 was synthesized from sodium silicate and cetyltrimethylammonium bromide (CTAB). The structure of MCM-41 synthesized at room temperatur was compared with MCM-41 synthesized by conventional hydrothermal method. The synthesized and calcined MCM-41 were used for adsorption of phosphate and methylene blue at various pH, contact time and adsorbate concentration. The effect of aging time and mole ratio of Si/Al on the structure of MCM-41 were evaluated by X-ray diffraction, infrared spectroscopy and adsorption desorption N2. The amount of adsorbate phosphate and methylene blue on MCM-41 were analyzed by using UV-Vis spectroscopy. Results showed that the optimum synthesis of MCM-41 obtained at room temperature with aging time of 48 hours and the molar ratio of Si/Al = 25. The optimum condition of phosphate adsorption on as-synthesized MCM-41 and Al- MCM-41 was obtained at pH 5.5 and contact time of 60 minutes, with the adsorption capacity of 50.27 mg.g-1 and 49.95 mg.g-1, respectively. The adsorption capacity of methylene blue on calcined Al-MCM-41 was more higher than calcined MCM-41.

Kata Kunci : MCM-41, Al-MCM-41, sintesis, adsorpsi, fosfat, metilen biru