SYNTHESIS OF In-CONTAINING HIGH-SILICA ZEOLITE OF ZSM-5 TYPE
Abstract
High silicate zeolite ZSM-5 on the basis of SiO2–In2O3–NaOH with an organic structure forming agent tetrabutylammonium iodide (TBAI) was synthesized in the temperature range of T = 150–220°C, pH = 9-12, τ = 48-240 h. As initial components, silica gel MSKO containing 86% SiO2, tetrabutylammonium iodide (TBAI), chemically pure NaOH and metallic indium (In) were used which mixed by hydrothermal synthesis. At the end of the synthesis, the solid product was separated from the mother liquor, washed on the filter with distilled water from an excess of alkali and dried at 120 °C, calcined at 550 °C (16 h). The products of hydrothermal crystallization were determined by X-ray (RFA – on the device D2-Phaser "Bruker"), differential thermal (DTA- STA-449 F3
Jupiter NETZSCH), by X-ray diffraction (XRD of brand SRM-18) and infrared spectroscopy (IR on FTIR spectroscopy, Nicolefisio VSA) analysis methods. During the synthesis, it was experimentally established that at T = 200 °C; τ = 240 h; pH≈9-10 molar ratio of components 5.78SiO2∙0.058In2O3∙0.625Na2O∙0.11H2O∙0.95 ((C4H9) 4NJ) – MFI-type zeolite is crystallized. When comparing XRF data with literature data, they were referred to a type zeolite of ZSM-5 differing in high degree of crystallinity. The following chemical composition of the synthesized zeolite (wt.%) was established by the X-ray diffraction (SRM-18) method: SiO2 – 94.01; In2O3 – 4.92; Na2O – 1.06 corresponding to the formula 0.96Na2O:In2O3:88SiO2:10H2O.
Forcitation:
Samedov Kh.R., Mamedova U.A., Ragimov K.G., Jabbarova Z.A. Synthesis of In-containing high-silica zeolite of ZSM-5 type.Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 8. P. 84-87.
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