A Study of Cordierite Ceramics Synthesis From domestic kaolin

This work aims to study the effect of chlorine ion on the formation of the cordierite phase (2MgO.2Al2O3.5SiO2) from domestic kaolin at various calcined temperatures.. The cordierite phase was synthesized by a solid-state reaction technique from the mixture of kaolin, aluminum nitrate nonahydrate (Al(NO3)3.9H2O), and magnesium chloride hexahydrate (MgCl2.6H2O) which was designed to the stoichiometric composition of cordierite in the absence and presence of chlorine ion (NH4Cl). The structure and formation of cordierite phase were characterized by X-ray diffraction (XRD) and thermogravimetric - differential thermal analysis (TG-DSC). Phase composition of samples calcined at various temperatures was calculated by using Match! (Version 3.7.0) software. It is noteworthy that the presence of chlorine ion in the mixture declined the formation temperature of cordierite by 50 °C. The cordierite phase was calculated to be 61.3 wt.% and 5.5 wt.% at 1150 °C for the present and absent chlorine ion, respectively. The presence of chlorine ion affected the cordierite formation rate and suppressed the temperature of formation. Cordierite phase could be obtained up to 89.6 wt.% at 1250 °C and 30 wt.% NH4Cl. This investigation found that cordierite ceramic could be synthesized from domestic kaolin at lower temperature by using NH4Cl additive.

Synthesis of metallic aluminum particles by electrolysis in aqueous solution

The present work proposes a method for fabricating metallic Al particles in aqueous solution. An aqueous colloidal solution was prepared from an aqueous aluminum nitrate nonahydrate solution by electrolysis using metallic Al plates as the anode and cathode under ultrasonic irradiation in water at 25–45 °C. The sizes of the particles in the colloidal solutions prepared at 25, 35, and 45 °C were 76.3, 77.0, and 84.7 nm, respectively. The powder obtained from the colloidal solution prepared at 25 °C was not crystalline. By contrast, the powders obtained from the colloidal solutions prepared at 35 and 45 °C had a crystal structure of cubic Al and crystal sizes of 55.7 and 59.3 nm, respectively. Thus, elevated temperatures promoted both particle growth and crystal growth, which was explained by higher temperatures increasing the frequency and energy of particle collisions. The metallic Al particles were chemically stable in both an aqueous solution and the ambient atmosphere. The chemically stable metallic Al particles are expected to be used as sources for fabricating materials related to fuels, energy storage, and pigments.

Ceramic Processing of Silicon Carbide Membranes with the Aid of Aluminum Nitrate Nonahydrate: Preparation, Characterization, and Performance

The development of a low-cost and environmentally-friendly procedure for the fabrication of silicon carbide (SiC) membranes while achieving good membrane performance is an important goal, but still a big challenge. To address this challenge, herein, a colloidal coating suspension of sub-micron SiC powders was prepared in aqueous media by employing aluminum nitrate nonahydrate as a sintering additive and was used for the deposition of a novel SiC membrane layer onto a SiC tubular support by dip-coating. The sintering temperature influence on the structural morphology was studied. Adding aluminum nitrate nonahydrate reduced the sintering temperature of the as-prepared membrane compared to conventional SiC membrane synthesis. Surface morphology, pore size distribution, crystalline structure, and chemical and mechanical stability of the membrane were characterized. The membrane showed excellent corrosion resistance in acidic and basic medium for 30 days with no significant changes in membrane properties. The pure water permeance of the membrane was measured as 2252 L h−1 m−2 bar−1. Lastly, the final membrane with 0.35 µm mean pore size showed high removal of oil droplets (99.7%) in emulsified oil-in-water with outstanding permeability. Hence, the new SiC membrane is promising for several industrial applications in the field of wastewater treatment.

Performance analysis and comparison of methyl-modified Al2O3/SiO2 xerogels fabricated by two methods

Two methyl-modified Al2O3/SiO2 xerogels, i. e. AIP-Al2O3/MSiO2 and ANN-Al2O3/MSiO2 xerogels, were prepared using aluminum isopropoxide and aluminum nitrate nonahydrate as the aluminum precursors, respectively. The appearance, density, viscosity, Gibbs activation energy for viscous flow and reaction rate constant of the sols were analyzed and compared. Their microstructures were characterized by means of powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and nitrogen adsorption–desorption measurements. The results show that the Al–O–Si bond is formed in the AIP-Al2O3/MSiO2 and ANN-Al2O3/MSiO2 xerogels. The ANN-Al2O3/MSiO2 sol has a smaller mean particle size and greater sol stability than the AIP-Al2O3/MSiO2 sol. Meanwhile, the ANN-Al2O3/MSiO2 xerogel has a smaller pore size and higher porosity. The total pore volume and specific surface area of the ANN-Al2O3/MSiO2 xerogel are 27.27% and 29.36% larger than those of the AIP-Al2O3/ MSiO2 sample, respectively. The saturated adsorption capacity of the ANN-Al2O3/MSiO2 xerogel to methylene blue is 7.15% larger than that of the AIP-Al2O3/MSiO2 xerogel.

In Situ Synthesis of Alumina Nanoparticles in a Binary Carbonate Salt Eutectic for Enhancing Heat Capacity

A binary carbonate salt eutectic (Li2CO3-K2CO3)-based nanofluid was in situ synthesized by mixing with a precursor material, aluminum nitrate nonahydrate (Al(NO3)3·9H2O). Thermal decomposition of the precursor was successfully carried out to synthesize alumina (Al2O3) nanoparticles at 1 wt.% concentration. A thermogravimetric analysis (TGA) confirmed a complete thermal decomposition of aluminum nitrate nonahydrate to alumina nanoparticles. A transmission electron microscope (TEM) was employed to confirm the size and shape of the in situ formed nanoparticles; the result showed that they are spherical in shape and the average size was 28.7 nm with a standard deviation of 11.7 nm. Electron dispersive X-ray spectroscopy (EDS) confirmed the observed nanoparticles are alumina nanoparticles. A scanning electron microscope (SEM) was employed to study microstructural changes in the salt. A differential scanning calorimeter (DSC) was employed to study the heat capacity of the in situ synthesized nanofluid. The result showed that the heat capacity was enhanced by 21% at 550 °C in comparison with pure carbonate salt eutectic. About 10–11 °C decrease of the onset melting point of the binary carbonate salt eutectic was observed for the in situ synthesized nanofluids.

Karakterisasi dan Uji Efektivitas Allophane-Like untuk Adsorpsi Ion Logam Tembaga (Cu)

<p>Telah dilakukan penelitian karakterisasi dan uji efektivitas <em>allophane-like</em> untuk adsorpsi ion logam tembaga (Cu). <em>Allophane-like</em> dibuat dengan mencampurkan larutan <em>Tetraethyl Orthosilicate</em> (TEOS) dan <em>Aluminum Nitrate Nonahydrate</em> [Al(NO₃)₃.9H₂O] dengan perbandingan 0,5; 0,75; 1; 1,25 dan 1,5. Proses pencampuran dilakukan penambahan NaOH secara bertahap dan dilakukan pengadukan serta pemanasan. Penambahan NaOH dilakukan dengan membuat perbandingan NaOH dan Campuran TEOS dan Al(NO₃)₃.9H₂O 3:1. pH campuran larutan yang diperoleh diukur dan pH larutan dibuat menjadi asam (pH 3-4). <em>Allophane-like</em><em> </em>dikarakterisasi dengan spektroskopi infra merah (FTIR), XRD, keasaman, dan luas permukaan. Uji adsorpsi terhadap ion logam tembaga (Cu) dilakukan pada variasi perbandingan TEOS dan Al(NO₃)₃.9H₂O 0,5; 0,75; 1; 1,25 dan 1,5, pH larutan tembaga (Cu) 3-7 serta waktu kontak 30-120 menit dengan sistem <em>batch</em>. Hasil penelitian diketahui bahwa <em>allophane-like </em>memiliki gugus fungsi yang sama dengan <em>allophane-</em><em>alam </em>yang ditunjukkan dengan data FTIR yaitu memiliki puncak yang sama pada 3431-3252; 1631; 1071; 785; dan 562-457 cm^-1. Hasil analisa XRD, keasaman dan luas permukaan menunjukkan karakteristik yang berbeda. Kondisi adsorpsi ion logam tembaga (Cu) terjadi pada variasi perbandingan TEOS dan Al(NO₃)₃.9H₂O 1,5, pH 6, waktu kontak 120 menit, persentase penyerapan 41,79% dan kapasitas adsorpsi 0,97865 mg/g.</p><p><strong>Characterization and Effectivity of </strong><strong>Allophane-Like </strong><strong>in</strong><strong> </strong><strong>the Adsorption of</strong><strong> </strong><strong>Metal Ion of Copper (Cu).</strong> The characterization and effectivity testing of allophane-like for adsorption copper (Cu) metal ion has been studied. Allophane-like was prepared by mixing a solution of Tetraethylorthosilicate (TEOS) and Aluminum Nitrate nonahydrate [Al(NO₃)₃.9H2O] using ratio of 0.5; 0.75; 1; 1.25 and 1.5. The mixing process was done gradually adding NaOH and stirring and heating. The addition of NaOH was done by making a comparison between NaOH and mixture of TEOS dan Al(NO₃)₃.9H₂O in 3:1. The pH of the mixture solution was measured and made acidic solution (pH 3-4). Allophane-like was characterized by infrared spectroscopy (FTIR), XRD, acidity, and surface area. The adsorption evaluation of copper (Cu) metal ion was done on the variation of the composition of TEOS dan Al(NO₃)₃.9H₂O in 0.5; 0.75; 1; 1.25 and 1.5, the pH of a solution of copper (Cu) 3-7 and contact time of 30-120 minutes in batch system. The results revealed that the allophane-like has the same functional group with nature allophane indicated by the FTIR data that has the same peak at 3431-3252; 1631; 1071; 785; and 562-457 cm^-1. XRD analysis results, acidity and surface area showed different characteristics. The best conditions adsorption of copper (Cu) metal ion occured at the composition of TEOS dan Al(NO₃)₃.9H₂O in 1.5, pH 6, the contact time of 120 minutes, the absorption percentage of 41.79% and adsorption capacity of 0.97865 mg/g.</p>

Investigation of the New Room Temperature Ionic Liquid of Al(NO3)3.9H2O with Urea CO(NH2)2

Mixing aluminum nitrate nonahydrate with urea produced room temperatures clear colorless ionic liquid with lowest freezing temperature at (1: 1.2) mole ratio respectively. Freezing point phase diagram was determined and density, viscosity and conductivity were measured at room temperature. It showed physical properties similar to other ionic liquids. FT-IR,UV-Vis, 1H NMR and 13C NMR were used to study the interaction between its species where - CO ??? Al- bond was suggested and basic ion [Al(NO3)4]? and acidic ions [Al(NO3)2. xU]+ were proposed. Water molecule believed to interact with both ions. Redox potential was determined to be about 2 Volt from – 0.6 to + 1.4 Volt with thermal stability up to 326 ?.