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This article reviews syntheses of mesoporous aluminosilicates and aluminum oxides based on surfactant templating methods. The incorporation of aluminum in the silicate frameworks generates acid sites and ion-exchange sites. Both, tetrahedral framework aluminum and octahedral extraframework aluminum can be present, depending on the aluminum precursor used. The aluminum-containing structures tend to be less ordered than their purely siliccous analogs. Dealumination plays a significant role during template removal. Other methods for the synthesis of mesoporous aluminum-containing sieves are based on the structural transformation of kanemite, and on cluster precursors which may be connected by self-condensation or by condensation with silicate bridges. Purely aluminous mesostructures can be prepared with neutral templates or by condensing Keggin-like aluminum clusters in an ordered salt with an anionic surfactant.

Solid acids comprising 12-tungstophosphoric acid and 12-tungstosilicic acid anchored on to metal oxide (ZrO2), zeolites (Hβ and HZSM-5), and mesoporous material (MCM-41) were synthesized, characterized and used as the catalysts. A solvent free green route to carry out the Biginelli cyclocondensation reaction is described over synthesized catalysts. The method provides an efficient and much improved protocol of Biginelli reaction in terms of solvent free conditions, high yields up to 98 %, very short reaction time of 15 min, and simple work-up procedure. Based on the above study a best catalyst among all is proposed and is recycled up to four times without any significant change in % yields of the product. Another important feature of this method is survival of a variety of functional groups under the reaction conditions.

The demand for transportation diesel fuels has been increasing in most countries for the last decade. As is one of the primary sources for diesel distillates, light cycle oil (LCO), having the advantages of inheriting similar density and boiling point range to diesel fuels, but high contents of aromatics, sulfur, and nitrogen, needs to be upgraded before being utilized. This work reports a trinary porous SiO2–Al2O3–TiO2 (SAT) synthesized by sol–gel method and used as the NiMo catalyst support for the LCO hydro-upgrading. NiMo/Al2O3-zeolite (AZ) was used as a reference to evaluate the performances of the NiMo/SAT. The catalysts were characterized by XRD, BET, Pyridine-FTIR, and TEM; and evaluated in a 20-mL fixed-bed microreactor using a Fluid Catalytic Cracking LCO as feedstock. It was found that the SAT support possessed a high surface area, high pore volume, and good acid properties. The NiMo/SAT catalyst exhibited even better hydrodesulfurization, hydrodenitrogenation, and hydrodearomatization performances than NiMo/AZ when the reaction was performed at 375 °C and 1100 psi. Compared with the zeolite addition catalyst, the SAT catalyst has the advantages of simple synthesis procedures and low input cost.

Nitrogen-containing mesoporous carbons with the use of colloidal silica spheres of (14 nm) and chitosan as a carbon precursor were obtained. A removal of such small template particles from carbonized silica–chitosan composite is difficult and HF with a minimum concentration of 15 wt% should be used. By varying the silica-to-chitosan ratio, the porous characteristic of products is controlled. The modification by ZnCl2 with a molar Zn-to-C (in chitosan mass) ratio of ‘6’ results in the development of microporosity; however it is accompanied by a significant reduction of mesopore volume (Vmes). The addition of ZnCl2 in a ratio of ‘5.25’ and pH adjustment to 5.8 increase the volumes of micropores, small mesopores, BET surface area to 1975 m2/g, and preserve Vmes of 4.15 cm3/g. The novelty of the presented strategy is the creation of microporosity in the hard-templated materials by incorporating ZnCl2 into the mixture of Ludox HS-40 template and chitosan precursor, as well as the investigation on how the pH of synthesis influences the final porosity. The pH of a silica–chitosan–zinc solution, equal to 3.9, provides some coordination of Zn2+ by –OH and –NH2 groups, whereas pH adjustment to 5.8 results in the precipitation of a new template—Zn(OH)2.

Mesoporous flower-like FeOOH nanostructure was synthesized via hydrolysis of flower-like iron glycolate in aqueous methylamine solution and ethanol as a solvent with a molar ratio of 1:350:52:44. Then mesoporous flower-like FeOOH nanostructure was transformed into mesoporous flower-like Fe3O4, γ-Fe2O3, and α-Fe nanostructures using reductive annealing under Ar or air atmosphere by adjusting the process factors such as reaction temperature and time. The nanostructures were studied and characterized by XRD, SEM, TEM, TGA, and BET analysis. The N2 adsorption–desorption analysis showed that the surface area of the as-synthesized mesoporous flower-like FeOOH, Fe3O4, γ-Fe2O3 and α-Fe nanostructures were 232 m2g−1, 128 m2g−1, 80 m2g−1, and 80 m2g−1, respectively. The nanostructures' porosity and morphology, due to the replacement of bulky glycolate molecules with smaller water molecules, were also investigated. The as-prepared nanostructures' catalytic activity was examined in the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4 as the reducing agent. The kinetic study was shown all as-prepared nanostructures exhibited high catalytic activity with pseudo-first-order kinetic constants of 0.0099, 0.0054, 0.0038, and 0.0027 s−1 for mesoporous flower-like FeOOH, α-Fe, γ-Fe2O3, and Fe3O4 nanostructure, respectively. Mesoporous flower-like FeOOH, due to having more rate constant rather than other catalysts, was separated easily by centrifugation and was recycled 4 times with an increased reaction time to 7 min in the final cycle. We deduced that specific surface area, morphology, and crystal structure played an essential role in reducing 4-NP to 4-AP reaction.

The electrospun PMMA/O-MMT microfibrous membranes were pretreated by oxygen plasma to create substrates with better adsorption capability. The amount of O-MMT and conditions of plasma treatment were optimized for maximum laccase immobilization on these pretreated surfaces of the microfibrous membranes. The surface morphology and chemistry of the composite microfibrous membranes after plasma treatment and laccase immobilization were investigated by SEM and FTIR. The immobilized laccase showed better resistance to pH and temperature changes than that of the free form laccase, and after 10 successive runs of repeated use, the immobilized laccase still retained 30 % of its initial activity. Reactive X-3B was successfully degraded by both free and immobilized laccase.

Acid-basic materials are often used to catalyse organic reactions. Hydroxyapatite is acidic and hydrotalcite presents basic properties. The association of both compounds in a single material should present a rather unique catalytic behavior. Three preparations of hydroxyapatite impregnated with hydrotalcite are presented. The effect of microwave irradiation, at different preparation levels, is discussed. A homogeneous distribution of hydrotalcite on hydroxyapatite surface is obtained when hydrotalcite is precipitated over a previously microwave irradiated hydroxyapatite. Instead, if the hydrotalcite mixture is incorporated to the hydroxyapatite precursor gel and the resulting mixture microwave irradiated, hydrotalcite is preferentially deposited in the hydroxyapatite interparticle spaces. When both hydroxyapatite and hydrotalcite solutions are irradiated, mixed and irradiated again, the composite behaves as the addition of the two components.

We demonstrate a novel solution growth method for synthesis of uniform and ordered periodic mesoporous organosilica (PMO) thin films on substrate. The approach is simple and facile, in which a substrate is immersed into a solution containing 1,2-bis(triethoxysilyl)ethane (BTSE) precursor, cetyltrimethylammonium bromide (CTAB) surfactant template, ammonia catalyst, ethanol, and decane. The precursors are hydrolyzed, cross-linked by ammonia catalyst, and assembled with the surfactant on the substrate to form highly ordered hexagonal mesostructures. The obtained mesoporous silica films possess substrate-size-dependent dimension, uniform and tunable thickness (30–100 nm), and ethane group incorporated frameworks. The obtained PMO films have been characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and grazing incidence small-angle X-ray scattering (GISAXS). The film thickness can be easily controlled by adjusting the reaction temperature. A formation mechanism of the ethane-bridged PMO films via CTAB directed sol–gel process is further proposed.

The anisotropic photonic crystals have been prepared by impregnating the interstitial voids of synthetic opals with CdS and ZnS. The interplay of coherent and incoherent scattering has been traced by reflectance and photoluminescence (PL) spectroscopy. The reduction of anisotropy of the photonic bandgap (PBG) structure with increasing loading has been observed, as compared with bare opal. The interplay between the photonic and electronic energy structures of the composite material results in an amplified spontaneous emission (ASE).