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• 13446-18-9 magnesium(II) nitrate 
• 7784-27-2 aluminium trinitrate 
• 497-19-8 sodium carbonate 
• 1310-73-2 sodium hydroxide 
• 7732-18-5 water 
• 2414-98-4 magnesium ethylate 
• 2269-22-9 aluminum tri-sec-butoxide 
• 1333-84-2 aluminum oxide 
• 142-72-3 magnesium acetate 

Relevant academic research and scientific papers

EFFECT OF ADDITIVES ON THE SURFACE AREA OF OXIDE SUPPORTS FOR CATALYTIC COMBUSTION

Effect of additives on the surface area of oxide supports was investigated to use them for combustion catalysts above 1000 deg C.An addition of BaO to Al2O3 was found to suppress the decrease of its surface area at elevated temperatures.The maximum surfac

Evaluation of crystalline structure and SO2 storage capacity of a series of composition-sensitive De-SO2 catalysts

A series of non-stoichiometric magnesium-aluminate solid solution spinels, used as sulfur-transfer catalysts in the fluid catalytic cracking units for SOx emissions abatement, were prepared by using coprecipitation method and characterized with BET, TGA, AES, XRD and in situ IR techniques. It was found that both the crystalline structures and De-SOx activities of magnesium-aluminate spinels are very sensitive to catalyst compositions. Several phase domains were produced by changing the mole ratio of alumina to magnesia in the preparation process. Owing to substitution of magnesium or aluminum ions in the spinel structure, that leads to a polarization of Al3+ or Mg2+ ions to adjacent oxygen lattices, the lattice cell parameter of spinel structure regularly varied with chemical compositions, producing a contraction or expansion effect in the lattice cell, that strongly affects De-SOx activity. TG analysis showed that during SO2 oxidative adsorption, most of sulfur species were captured on the surface and some sulfur species were stored in bulk of the solids. The IR and AES results confirmed that both surface and bulk-like sulfates with different H2-reducibilities were formed on the catalysts, which is in good agreement with results of SO2 monolayer adsorption measurement. Ten-cycle tests of SO2 oxidative adsorption and reductive decomposition of the formed sulfate showed that the sample with XAl = 0.33 is the optimum catalyst, its SO2 capturing capacity reached 124.4 mg/g.

Guerbet condensation of methanol with n-propanol to isobutyl alcohol over heterogeneous copper chromite/Mg-Al mixed oxides catalysts

The synthesis of isobutyl alcohol (iBuOH) from methanol (MeOH) and n-propanol (PrOH) through the Guerbet condensation was studied at 200°C and under inert atmosphere (3 MPa of N2, using a two-component heterogeneous catalytic system based on pre-activated copper chromite and Mg-Al mixed oxides deriving from hydrotalcite-type precursors with different Mg/Al ratios. The catalyst productivity increased by reducing the Mg/Al ratio in the heterogeneous base, according to the increase of the fraction of medium-strong and strong basic sites, which favor the aldol condensation between the aldehydes derived from MeOH and PrOH. The heterogeneous base with the lowest Mg/Al atomic ratio exhibited the maximum of productivity in iBuOH when employed in the lowest amount, thus opening interesting application perspectives.

The Influence of the Nature of the Support on the Copper-Palladium Catalysed Suzuki-Miyaura-Coupling

Copper-palladium bimetallic catalysts supported on mixed oxides (MgO)0.75(Al2O3)0.25 (MgAlO) were prepared with two step impregnation (TSI) and co-impregnation (CI). These materials were studied to determine the effect of the support on the activity and stability in the Suzuki-Miyaura reaction and on the properties of a catalyst. The catalyst prepared by CI was active and selective during 6 catalytic cycles in Suzuki coupling, whereas the activity of the catalyst prepared with TSI dropped at the sixth use. The kinetics of the reaction was examined along with its scope. The relationship between the basic properties of the support and the catalytic performances were examined too. The importance of the nature of the support was also studied by catalyst characterization methods. (Chemical Equation Presented).

Analysis of the catalytic activity induction and deactivation of PtIn/Mg(Al)O catalysts for propane dehydrogenation reaction

The catalytic activity induction and deactivation of PtIn/Mg(Al)O catalysts for propane dehydrogenation reaction are experimentally verified. Numerous physical-chemical characterizations are employed to probe the basis and structure-activity relationships, and a mechanism for the activity induction and deactivation is proposed with the help of a schematic diagram. XPS results prove that the valence state of In exhibits almost no change during the entire dehydrogenation reaction. In the activity induction period, the average metal particle size of the PtIn/Mg(Al)O catalyst presents a decreasing trend, and the specific surface area increases. Moreover, the crystal phase changes from primarily periclase (MgO) to dominantly meixnerite (Mg6Al2(OH)18·4H2O). Coke is mainly deposited on the carrier. Nevertheless, in the deactivation period, the metal particles tend to agglomerate and grow. The specific surface area decreases and crystal phase returns to the unique periclase crystal phase. A large amount of coke is formed over the catalyst and partially covers the active sites, which leads to the evident decrease of catalytic activity.

One-pot synthesis of potassium-loaded MgAl oxide as solid superbase catalyst for Knoevenagel condensation

We report a new strategy for one-pot synthesis of potassium-loaded MgAl oxides using KOH to adjust the pH value of the reaction system. The as-prepared solid superbases were studied by N2 physisorption method, energy-dispersive X-ray spectrosco

Catalytic system and process for the production of hydrogen

Catalytic system for the production of hydrogen consisting of an active component based on iron and a micro-spheroidal carrier based on alumina and represented by the following formula [Fex1Mx2Qx3Dx4Alx5]Oy wherein xi with i=1.5 represent the atomic percentages assuming values which satisfy the equation Σxi=100. y is the value required by the oxidation number with which the components are present in the formulate, x1 is the atomic percentage with which Fe is present in the formulate and ranges from 5 to 80, preferably from 20 to 50, M is Cr and/or Mn, x2 ranges from 0 to 30, preferably from 0 to 10, Q is La, Lanthanides (with Ce particularly preferred), Zr or a combination thereof, x3 ranges from 0 to 30, preferably from 0 to 10, D is Mg, Ca, Ba, Co, Ni, Cu, Zn or combinations thereof, x4 ranges from 0 to 35, preferably from 5 to 25, x5 is the atomic percentage with which Al is present in the formulate and ranges from 20 to 95, preferably from 50 to 80.

New treatment method for dilute hydrochloric acid using magnesium-aluminum oxide

Magnesium-aluminum oxide (Mg-Al oxide) was shown to be superior to CO32- intercalated hydrotalcite (CO3-HT) for removing dilute hydrochloric acid. Cl- in a 0.5 M HCl solution could be quantitatively removed by adding 1.75-times the stoichiometric quantity of Mg0.70Al0.20O at 60 °C for 1 h. The solution after the reaction was weakly alkaline. This reaction could be adequately described as being first order for the HCl concentration, and the apparent activation energy was 49.3 kJ mol-1. The amount of Cl- removal per 1 g of Mg-Al oxide in the first use was 3.08 meq at a Mg/Al molar ratio of 2.0 and 2.89 meq at a ratio of 3.5.

New treatment methods for waste water containing chloride ion using magnesium-aluminum oxide

The removal of hydrochloric acid utilizing magnesium-aluminum oxide (Mg-Al oxide), as prepared by the thermal decomposition of hydrotalcite (HT), was investigated. Cl- in hydrochloric acid can be removed almost 100% by adding 1.75 times the sto

Structure and surface and catalytic properties of Mg-Al basic oxides

Mg-Al mixed oxides with Mg/Al molar ratios of 0.5-9.0 were obtained by thermal decomposition of precipitated hydrotalcite precursors. The effect of composition on structure and surface and catalytic properties was studied by combining several characterization methods with ethanol conversion reactions. The nature, density, and strength of surface basic sites depended on the Al content. On pure MgO, strong basic sites consisted predominantly of O2- anions. Calcined hydrotalcites contained surface sites of low (OH- groups), medium (Mg-O pairs), and strong (O2- anions) basicity. The relative abundance of low and medium strength basic sites increased with the Al content. The addition of small amounts of Al to MgO diminished drastically the density of surface basic sites because of a significant Al surface enrichment. Formation of surface amorphous AlOy structures in samples with low Al content (Mg/Al > 5) partially covered the Mg-O pairs and decreased the concentration of surface O2- anions. At higher Al contents (5 > Mg/Al > 1), the basic site density increased because the Al3+ cations within the MgO lattice created a defect in order to compensate the positive charge generated, and the adjacent oxygen anions became coordinatively unsaturated. In samples with Mg/Al 2O4 spinels occurred and caused the basic site density to diminish. The catalyst activity and selectivity of Mg-Al mixed oxides in ethanol conversion reactions depended on composition. The dehydrogenation of ethanol to acetaldehyde and the aldol condensation to n-butanol both involved the initial surface ethoxide formation on a Lewis acid-strong base pair. Pure MgO exhibited poor activity because the predominant presence of isolated O2- basic centers hindered formation of the ethoxide intermediate by ethanol dissociative adsorption. The incorporation of small amounts of Al3+ cations to MgO drastically increased the acetaldehyde formation rate because of the generation of new surface Lewis acid-strong base pair sites. Acetaldehyde condensation toward n-butanol is a bimolecular reaction between adjacent adsorbed acetaldehyde species that requires not only acid-strong base pair sites but also a high density of basic sites; these pathways were favored on Mg-Al samples with higher Al content (5 > Mg/Al > 1). The dehydration of ethanol to ethylene, and the coupling and dehydration to diethyl ether increased with Al content, probably reflecting the density increase of both Al3+-O2- pairs and low- and medium-strength basic sites. Pure Al2O3 displayed the highest dehydration activity.