Chemical Engineering

Sulfonated niobia and pillared clay as catalysts in etherification reaction of glycerol
Sulfonated niobia (HY-340 CBMM) and pillared clay (Fluka) were tested in the catalytic conversion of glycerol by etherification reactions. The solids were treated with concentrated fuming sulfuric acid (AS100 and NS100), and a 30% aqueous solution of this acid (AS30 and NS30). Both the presence of sulfur and the increase in the acidity of the solids demonstrate the suitability of the sulfonatio...


XAFS and HAADF STEM combined characterization for size regulated Ni nanocluster catalyst and its unique size dependence for water gas shift reaction
X-ray absorption fine structure (XAFS) and high angle annular dark field scanning transmission electron microscopy (HAADF STEM) were both applied to a characterization of the size regulated Ni nanocluster catalyst on alumina. XAFS analysis showed that NiAl2O4 was not formed in our colloid derived catalyst. The wide variety of coordination number (CN) for Ni–Ni indicated the achievement of the...
Promoting mechanism of sulfur addition in catalytic dehydrogenation of isobutane over Mo/MgAl2O4 catalysts
Mo/MgAl2O4 catalysts with sulfur addition were verified to exhibit excellent performance in catalytic dehydrogenation of isobutane, which could yield up to 56.3wt% isobutene at 560°C. Catalyst characterization and activity test results jointly revealed that MoS2 formed during the induction period probably constituted the active phase for dehydrogenation. As to the formation of MoS2, treatment ...


Molecular size- and shape-selective Knoevenagel condensation over microporous Cu3(BTC)2 immobilized amino-functionalized basic ionic liquid catalyst
A novel molecular size- and shape-selective catalyst, microporous metal-organic framework HKUST-1 immobilized amino-functionalized basic ionic liquid (ABIL-OH), was synthesized by facile impregnation and activation. Characterizations and catalytic results revealed that the catalytically active species aBIL-OH could be confined in well-defined HKUST-1 nanocavities via CuNH2 coordination bond. Th...
Graphene dispersions
Aqueous dispersions of graphene are of interest to afford environmentally safe handing of graphene for coating, composite, and other materials applications. The dispersion of graphene in water and some other solvents using surfactants, polymers, and other dispersants is reviewed and results show that nearly completely exfoliated graphene may be obtained at concentrations from 0.001 to 5% by wei...


Multiple light scattering as a probe of foams and emulsions
Light propagating in foams or emulsions is strongly scattered by the gas–liquid or liquid-liquid interfaces. This feature makes it generally impossible to directly observe the structure and dynamics deep within the bulk of such materials. However, multiple light scattering can be used as the basis of non-invasive experimental techniques that probe the average bubble size, droplet size or the ...
Taguchi's methodology for determining optimum operating conditions in hydrothermal pretreatments applied to canola seeds
The aim of the present work was to determine the optimum operating conditions in hydrothermal pretreatments applied to canola seeds. The effect of these pretreatments on the canola oil extraction yield and quality was evaluated. Samples were characterized by proximate analysis. Acidity and peroxide value were studied as parameters for the determination of oil quality. Seeds were exposed to dire...

Characterization of greywater in an indian middle-class household and investigation of physicochemical treatment using electrocoagulation
Wastewater produced from all the domestic uses of water sans toilet flushing is known as greywater. It is often the major component in the domestic wastewater but has fewer pollutant load. Recycling and reuse of treated grey water for non-potable purposes may significantly reduce the stress on the fresh water requirement. This article presents the result of a study undertaken for characterizati...
Fe3O4@LDH@Ag/Ag3PO4 submicrosphere as a magnetically separable visible-light photocatalyst
A novel visible-light responsed photocatalyst Fe3O4@LDH@Ag/Ag3PO4 submicrosphere has been successfully prepared by using PO4 3- intercalated layered double hydroxides (LDH) layers as the intermedium for the formation of ag3PO4 on the surface of Fe3O4@LDH microspheres. X-ray diffraction (XRD), X-rays photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission spectrum (ICP-AES),...

Effect of different metal in situ growing routes on the morphology and gas separation properties of polyetherimide/palladium nanocomposite asymmetric membranes
Here we report on an innovative synthesis of polymer/palladium asymmetric membrane that allows a control of the membrane morphology, the specific location of in situ grown Pd nanoparticles within the membrane and significant enhancement of H2 permeance values with respect to the reference polymer membrane. Materials and method: Nanocomposite asymmetric films have been prepared from polyetherim...
Thermal instability of a closed loop pulsating heat pipe: Combined effect of orientation and filling ratio
A multi-turn Closed Loop Pulsating Heat Pipe (CLPHP) made of copper (I. D. 1.1mm, O. D. 2mm), filled with FC-72 is experimentally investigated. The study focuses in particular on the combined effect of the inclination angle (gravity) and the filling ratio at different heat input levels on the device operation stability and the thermal performances. show that this CLPHP is very much sensitive to...

Spreading and receding characteristics of a non-Newtonian droplet impinging on a heated surface
The present study aims to investigate the influence of the Weber number and surface temperature on the spreading and receding characteristics of Newtonian (DI-water) and non-Newtonian (xanthan gum solution) droplets impinging on heated surfaces. The surface temperature was in the range from 25°C to 85 °C, which is below the Leidenfrost temperature (∼ 300 °C). Using high-speed camera images...
Experimental Investigation of Natural Dehumidification over an Annular Finned-tube
In this study, heat and mass transfer during natural condensation of humid air over a horizontal annular finned-tube is investigated experimentally. The finned-tube is made by extruded process and fins are circular with rectangular cross-section. Outer diameter of central tube, fin diameter, fin thickness and fin density are 25.4 mm, 0.4 mm, 56.0 mm and 433 FPM (fins per meter), respectively. T...
Comparative study on thermal performance of twisted tape and wire coil inserts in turbulent flow using CuO/water nanofluid
Heat transfer and friction factor analysis of CuO/water nanofluid flowing through a tube under turbulent flow conditions and with twisted tape and wire coil (WC) inserts were presented in this paper. The experimental investigations were performed in the Reynolds number range from 4000 to 20000, volume concentrations of 0.1% and 0.3%, twisted tape inserts of h/d =5 and 10 and wire coil inserts o...
Freezing of Water Droplets on Solid Surfaces: An Experimental and Numerical Study
We present an experimental and numerical study on the freezing of static water droplets on surfaces with different wettability when the surfaces are subject to rapid cooling. Temperature evolution of the droplets is recorded using both intrusive and non-intrusive methods to identify the processes involved in the cooling and phase change of the droplets. It is found the time taken for a droplet ...