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Full-Text Articles in Structural Materials
Sulfonic Acid Functionalized Mcm-41 As Solid Acid Catalyst For Tert-Butylation Of Hydroquinone Enhanced By Microwave Heating, Eng-Poh Ng
Eng-Poh Ng
Covalently linked sulfonic acid (-SO3H) modified MCM-41 mesoporous catalysts was prepared, characterized and its catalytic activity under microwave irradiation was evaluated. The NH2-MCM-41 was first prepared by anchoring (3-aminopropyl)triethoxysilane (APTES) on Si-MCM-41 and further reacted with 1,4-butane-sultone to yield the desired acid catalyst. The mesophase and porosity of samples were determined by XRD, TEM and N2 sorption isotherm analyses. The presence of sulfonic acid moiety was confirmed by FT-IR, TG/DTA, sulfur elemental analysis and in situ IR study of pyridine and ammonia adsorptions. The catalyst showed high catalytic activity and high selectivity in tert-butylation of hydroquinone under microwave irradiation. No …
Discrete Mnalpo-5 Nanocrystals Synthesized By An Ionothermal Approach, Eng-Poh Ng, Satpal Singh Sekhon, Svetlana Mintova
Discrete Mnalpo-5 Nanocrystals Synthesized By An Ionothermal Approach, Eng-Poh Ng, Satpal Singh Sekhon, Svetlana Mintova
Eng-Poh Ng
Discrete MnAlPO-5 nanocrystals with monomodal particle size distribution (diameter of 80 nm) were synthesized using an ionothermal technique; the pore filling effect of the ionic liquid molecules during the synthesis of microporous nanocrystals is verified.
Selective Capture Of Water Using Microporous Adsorbents To Increase The Lifetime Of Lubricants, Eng-Poh Ng, Luc Delmotte, Svetlana Mintova
Selective Capture Of Water Using Microporous Adsorbents To Increase The Lifetime Of Lubricants, Eng-Poh Ng, Luc Delmotte, Svetlana Mintova
Eng-Poh Ng
Eco-recycling towards an increase of the lifetime of lubricating mineral oil by selective capturing of water with nanosized microporous aluminophosphate and aluminosilicate materials is reported. Quantitative water measurements of oxidized lubricating oil before and after treatment with microporous materials were carried out by FT-IR spectroscopy combined with Karl Fischer titration method. The high selectivity of the nanosized aluminophosphate to water without adsorbing other additives in comparison to nanosized aluminosilicates that are adsorbing altogether polar oxidation products, ionic additives and water are revealed. A removal of nearly 98 % of moisture from the lubricating oil at ambient condition is achieved, which …
Nanoporous Materials With Enhanced Hydrophilicity And High Water Capacity, Eng-Poh Ng, Svetlana Mintova
Nanoporous Materials With Enhanced Hydrophilicity And High Water Capacity, Eng-Poh Ng, Svetlana Mintova
Eng-Poh Ng
The main types of nanoporous adsorbents for water are identified and described with emphasis on the mechanism of adsorption, modification, improvement of the water sorption capacity, possible regeneration, and stabilization. Among the three main groups of water sorbents, i.e. inorganic materials (zeolites, clays, silica), carbon based materials and organic polymers, the first one is described in details. The significance of their porosity, chemical and structural features relative to the water adsorptive properties of each inorganic type materials is reviewed. Important features for silicates, zeolites, aluminophosphates, mesoporous materials and clays are described, which define the interactions between the water and the …
What More In Nanosized Molecular Sieves, Eng-Poh Ng, Gerardo Majano, Louwanda Lakiss, Svetlana Mintova
What More In Nanosized Molecular Sieves, Eng-Poh Ng, Gerardo Majano, Louwanda Lakiss, Svetlana Mintova
Eng-Poh Ng
No abstract provided.
Sulphated Almcm-41: Mesoporous Solid Brønsted Acid Catalyst For Dibenzoylation Of Biphenyl, Eng-Poh Ng, Hadi Nur, Mohd Nazlan Mohd Muhid, Halimaton Hamdan
Sulphated Almcm-41: Mesoporous Solid Brønsted Acid Catalyst For Dibenzoylation Of Biphenyl, Eng-Poh Ng, Hadi Nur, Mohd Nazlan Mohd Muhid, Halimaton Hamdan
Eng-Poh Ng
Sulphated mesoporous solid Brønsted acid catalyst (SO4-AlMCM-41) was prepared by impregnation of sulphuric acid on the surface of H-AlMCM-41. Characterization of SO4-AlMCM-41 by pyridine adsorption studies and 27Al MAS NMR showed that the presence of Brønsted acidity was correlated with octahedrally coordinated aluminium and solvent environment. Catalytic study demonstrated that the SO4-AlMCM-41 catalyst has a higher activity in the dibenzoylation of biphenyl with benzoyl chloride than sulphuric acid, H-AlMCM-41 and sulphated amorphous silica.