Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene

Epoxides are one of the important intermediates for the synthesis of oxyoencontaining organic compounds as they undergo ring-opening reactions easily to form bifunctional compounds. Homogeneous catalysts have been used in producing epoxide compounds but due to the demand for environmentally clean...

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Main Author:	Nur Fatin Diana Binti Che Husin
Format:	Thesis
Language:	English
Subjects:	Epoxy compounds Organic compounds > Synthesis.
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id	my-usim-ddms-12421
record_format	uketd_dc
institution	Universiti Sains Islam Malaysia
collection	USIM Institutional Repository
language	English
topic	Epoxy compounds Epoxy compounds Organic compounds--Synthesis.
spellingShingle	Epoxy compounds Epoxy compounds Organic compounds--Synthesis. Nur Fatin Diana Binti Che Husin Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene
description	Epoxides are one of the important intermediates for the synthesis of oxyoencontaining organic compounds as they undergo ring-opening reactions easily to form bifunctional compounds. Homogeneous catalysts have been used in producing epoxide compounds but due to the demand for environmentally clean reactions, heterogeneous catalysts have attracted considerable attention to replace homogeneous, polluting and corrosive acid catalysts. In this study, metal complexes of MoO, (acac), and VO(acac), at various concentration were immobilized onto montmorillonite-K 10 (MMT-K10) and characterized using X-ray diffractogranl (XRD), atomic absorption spectroscopy (AAS), N, adsorption analysis. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The materials were labeled as KI 0-Mo or K IO-V (1-4), where numerical I. 2,3 and 4 indicate 0.05 M, 0.1 M, 0.15 M and 0.2 M of metal complexes concentration respectively. The immobilized MMT-K 10 samples were then tested for epoxidation of' cyclohexene with tert-butylhydroperoxide (TBHP). XRD analysis showed that MMTK10 retained its structure even alter metal complexes were introduced. This was proven by the diffractogranl patterns Ihr immobilized MMT-K10 samples with door basal spacing at 89° were 9.9 A- 10.0 A similar to the unmodified MMT-K 10. The intensities of 19.9° and 35° peaks were found to decrease that results in reducing crystallinity for immobilized MMT-K 10 samples. Characterization using N2 adsorption revealed a lower Brunauer-Emmett-Teller (BET) surface area for samples with high concentration of metal complexes relative to the unmodified MMT-K10. The pore size calculated from Barrett-Joyner-Halenda (B. IH) equation showed increasing pore size in the presence of higher metal elements, due to the substitution of shorter Si-O bond with a longer Mo-O or V-O bond lengths. A lot of deposition of the small particles of metal complexes on the surface of modified clays was observed from SEM images. Large particle size on the immobilized clay resulted in less crystalline material, as obtained from XRD dilfragtogram. More random shape of particles and high degree of dispersion of Mo or V species on clay surface enhances the catalyst performance in the epoxidation reaction. From the TGA results, high concentration of metal complexes Immobilized on MMT -K 10 structure make them being better hydrophobic nature and thus, lower the loss of physisorbed water molecules weakly bound to the material. MMT-K 10 gives a lower selectivity in epoxidation reaction because the opening of oxirane may be accelerated due to existence of higher -OH compared to immobilized MMT-K 10. The selectivity increased as the metal complexes used increased in both homogeneous (32 °o for Moo and 76 % I'm- Mo4) and heterogeneous (20 °o fir KIO-M04 and 70 (a Im- KIO-V4) catalytic system. This is because K10-Mo and K IO-V in higher concentration of metal complexes have bigger pore size although in smaller surface area, that resulted in the optimum interactions between the reactant and Mo or V active sites.
format	Thesis
author	Nur Fatin Diana Binti Che Husin
author_facet	Nur Fatin Diana Binti Che Husin
author_sort	Nur Fatin Diana Binti Che Husin
title	Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene
title_short	Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene
title_full	Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene
title_fullStr	Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene
title_full_unstemmed	Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene
title_sort	immobilized metal complexes on montmorillonite-k10 as heterogeneous catalyst for epoxidation of cyclohexene
granting_institution	Universiti Sains Islam Malaysian
_version_	1812444867112992768
spelling	my-usim-ddms-124212024-05-29T04:07:04Z Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene Nur Fatin Diana Binti Che Husin Epoxides are one of the important intermediates for the synthesis of oxyoencontaining organic compounds as they undergo ring-opening reactions easily to form bifunctional compounds. Homogeneous catalysts have been used in producing epoxide compounds but due to the demand for environmentally clean reactions, heterogeneous catalysts have attracted considerable attention to replace homogeneous, polluting and corrosive acid catalysts. In this study, metal complexes of MoO, (acac), and VO(acac), at various concentration were immobilized onto montmorillonite-K 10 (MMT-K10) and characterized using X-ray diffractogranl (XRD), atomic absorption spectroscopy (AAS), N, adsorption analysis. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The materials were labeled as KI 0-Mo or K IO-V (1-4), where numerical I. 2,3 and 4 indicate 0.05 M, 0.1 M, 0.15 M and 0.2 M of metal complexes concentration respectively. The immobilized MMT-K 10 samples were then tested for epoxidation of' cyclohexene with tert-butylhydroperoxide (TBHP). XRD analysis showed that MMTK10 retained its structure even alter metal complexes were introduced. This was proven by the diffractogranl patterns Ihr immobilized MMT-K10 samples with door basal spacing at 89° were 9.9 A- 10.0 A similar to the unmodified MMT-K 10. The intensities of 19.9° and 35° peaks were found to decrease that results in reducing crystallinity for immobilized MMT-K 10 samples. Characterization using N2 adsorption revealed a lower Brunauer-Emmett-Teller (BET) surface area for samples with high concentration of metal complexes relative to the unmodified MMT-K10. The pore size calculated from Barrett-Joyner-Halenda (B. IH) equation showed increasing pore size in the presence of higher metal elements, due to the substitution of shorter Si-O bond with a longer Mo-O or V-O bond lengths. A lot of deposition of the small particles of metal complexes on the surface of modified clays was observed from SEM images. Large particle size on the immobilized clay resulted in less crystalline material, as obtained from XRD dilfragtogram. More random shape of particles and high degree of dispersion of Mo or V species on clay surface enhances the catalyst performance in the epoxidation reaction. From the TGA results, high concentration of metal complexes Immobilized on MMT -K 10 structure make them being better hydrophobic nature and thus, lower the loss of physisorbed water molecules weakly bound to the material. MMT-K 10 gives a lower selectivity in epoxidation reaction because the opening of oxirane may be accelerated due to existence of higher -OH compared to immobilized MMT-K 10. The selectivity increased as the metal complexes used increased in both homogeneous (32 °o for Moo and 76 % I'm- Mo4) and heterogeneous (20 °o fir KIO-M04 and 70 (a Im- KIO-V4) catalytic system. This is because K10-Mo and K IO-V in higher concentration of metal complexes have bigger pore size although in smaller surface area, that resulted in the optimum interactions between the reactant and Mo or V active sites. Universiti Sains Islam Malaysian 2018-04 Thesis en https://oarep.usim.edu.my/handle/123456789/12421 https://oarep.usim.edu.my/bitstreams/1c59153a-7a37-45d6-9a3a-0d47ca52951f/download 8a4605be74aa9ea9d79846c1fba20a33 https://oarep.usim.edu.my/bitstreams/dbaa4194-c4e7-4332-94fe-9f1bdd38d106/download 7b8b95af7119683f8c8d083a3866fce8 https://oarep.usim.edu.my/bitstreams/5fb4b9df-0951-424a-b2a1-2d03bc4b2144/download 89cf489fb314a279ec66d0c5b54425de https://oarep.usim.edu.my/bitstreams/e587db79-5e63-44a4-a48b-5adb73a67a73/download 5445a336f4a69ee3826e55ad513446f6 https://oarep.usim.edu.my/bitstreams/0a2d2583-c681-4406-8cdc-adf87355bd16/download 714df0b31ff3a97493fd1d36aedc829b https://oarep.usim.edu.my/bitstreams/e4c4a9a1-f7f4-4493-98cb-cf6a457ebb93/download 1052539232ed488916afff38b548d91f https://oarep.usim.edu.my/bitstreams/b8b38ff0-be77-46cb-ba53-588d301a66dc/download 9f7ae6b94ea83c1dad3a6182a28ac2b9 https://oarep.usim.edu.my/bitstreams/a7366da2-8076-4f9f-be9b-0b91ef857863/download cb023fc978a6dfaa757a973f5fc07099 https://oarep.usim.edu.my/bitstreams/c0c11acb-6478-46d1-8c1e-9d73e3a87691/download 081f6996ad5fbcf0d81b6c14cf34fba1 Epoxy compounds Chemistry, Organic Organic compounds--Synthesis.

Immobilized Metal Complexes On Montmorillonite-K10 As Heterogeneous Catalyst For Epoxidation Of Cyclohexene

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