Latest issue

International Review of Chemical Engineering (Rapid Communications) - January 2010 - Papers

EDITORIAL
Hydrodynamic Characteristics of Mixing in Three Phase System
Evanescent Magnetic Field Effect on Transient State of Natural Convection
Kinetic, Equilibrium and Thermodynamic Studies of the Biosorption of Cd(II) and Pb(II) from Solutions Using Siam Leaf
(Chromolaena Odorata)
Usage of Pulp and Paper Secondary Sludge for Biocomposite Production: FTIR and DSC Analysis
Simultaneous Hydrodynamic and Thermal Flow Development of a Thermodependent Viscoplastic Fluid
Mean Porosity and Pressure Drop Measurements in Packed Beds of Monosized Spheres: Side Wall Effects
Intensified Pyrolysis of Biomass in Hydrothermal Media

Special Section on 1st Conference on Chemical Engineering and advanced materials (CEAM) Virtual forum november 23rd - december 8th 2009DECEMBER 8TH, 2009

Integrated Multiphysics Modeling in Materials and Manufacturing Processes
Algal Biorefinery: a Road towards Energy Independence and Sustainable Future
Flow of Debris Formed from an Explosion-Damaged Construction
The Effect of Carbon Dioxide on Hydrogen Embrittlement Behaviours of P110 Steel in Buffered NaCl Solution Dissolved High Contents of Hydrogen Sulfide and Carbon Dioxide
The Effect of Composition and Temperature on the Rheological Properties of Greases Based on Calcium Soaps
Lattice Boltzmann Computation of Plasma Jet Behaviours: Part II Argon-Azote Mixture
The Effect of Vane Angle on the Mist Eliminator Efficiency
BEA and FAU Type Zeolites in Phenol Removal from Wastewaters: Effect of Hydrophobicity
Dynamic Simulation of a Proton Exchange Membrane Fuel Cell
Influence of Fuel Oxygen on Diesel Combustion, Engine Performance, Ultrafine Particles, THC, CO, Smoke and NOx Emissions
The Evaluation of the Secondary Ulexite Mineral as a Neutron Shielding Material
Kinetics Study of CO₂ Capturing as Hydrate in Saline Water
Innovative System to Treat Winery Wastewater: Mathematical Modeling
A Proposal of Portable Equipment for Pretreatment in Chemical Analysis
The Use of Redox Mediators for Enhancing the Decolourisation of Orange G in a Sequencing Batch Reactor (SBR)
Influence of Intermittent Loading on the Removal of High Concentrations of VOCs in a Biofilter
Inhomogeneous Magnetic Field Effects on the Hydrodynamic Properties of Multiphase Catalytic Reactors
MDDSS: a New Software for Multicomponent Distillation Design and Simulation
New Method to Simulation of a Vacuum Distillation Unit in the Refining Process of Oil and the Reducing of the
Vacuum Residue Generation
A Comparison between the Predictions of Sequencing Batch Reactor (SBR) Models with Generalized Regression and Dynamic Neural Networks
Diffusion in Isothermal Ternary Gas Mixtures
Stochastic Analysis in the Visco-Elastic Impact Condition
Chemical Modification of Carbon Blacks with Maleic Acid in Different Solvents
Solid-State Synthesis of Sodium Metaborate for Hydrogen Storage Application
Fast Template-Free Synthesis of Flower-Like Cobalt Nanostructures
A Kinetic Study of Kurnakovite Dehydration: Coats-Redfern Model and Kinetic Compensation Effect

Computer Modeling of Microporous Materials (Book Review)

International Review of Chemical Engineering (Rapid Communications) - Papers

EDITORIAL

by Jordan Hristov

Vol. 2. n. 1, pp. 1

Hydrodynamic Characteristics of Mixing in Three Phase System
by Abbas H. Sulaymon, Emad F. Mansour, Asawer A. Alwasiti, Mohammed A. Kassim

Vol. 2. n. 1, pp. 2-9

Abstract - The hydrodynamic behavior of bubble column has been studied for various non-Newtonian liquid (Carboxy Methyl Cellulose solution). The critical gas velocity (VGC) for complete suspension of the sand particles range (63-250)μm in low aspect ration (L/D=0.8-1.4) is obtained. The mixing time, the intensity of mixing have been measured in a cylindrical hemispherical bottom gas sparged vessel (diameter=0.46m, height=1m), for three air spargers (single ring, double ring, and 4-arms) with different numbers and size of holes (1mm, 2mm, and 3mm). Electroresistivity probe was adopted in this work, contained two electrodes, one vertical above the other and separated by a known distance (0.85 cm), to measure the local gas hold-up, bubble frequency, bubble velocity, bubble size and number of bubbles by using the personal computer. The probe detects the difference in conductivity of gas and liquid.

Keywords: Three Phase System, Bubble Characteristic, Non-Newtonian Liquid, Critical Gas Velocity.

Evanescent Magnetic Field Effect on Transient State of Natural Convection
by Atef El Jery, Nejib Hidouri, Mourad Magherbi, Ammar Ben Brahim

Vol. 2. n. 1, pp. 10-17

Abstract - This paper numerically investigates the effect of an externally evanescent magnetic field on flow patterns and heat transfer of fluid in a square cavity. The horizontal walls of the enclosure are assumed to be insulated while the vertical walls are kept isothermal. A control volume finite element method is used to solve the conservation equations. The effect of constant Hartmann number on Nusselt number was studied. Validation tests with existing data demonstrate the aptitude of the present method to produce accurate results. The effects of inclination magnetic field angle from 0° to 90° on streamlines distributions are shown for different value of Hartmann number. For Grashof number equal to 105, the values of relaxation time of the magnetic field are chosen, so that the Lorentz force acts only during the startup transient of the natural convection flow. The Nusselt number was calculated for different values of the inverse relaxation time varying from 0 to +. The magnitude and the number of oscillations of the Nusselt number were observed. It has been found that no oscillation was seen at relaxation time equal to 20. Stream lines maps are plotted for different values of dimensionless time. The effect of relaxation time on the transition from single-cell to double-cell configuration was observed.

Keywords: Cavity, Convection, Heat Transfer, Magnetic Field, Finite Element Method.

Kinetic, Equilibrium and Thermodynamic Studies of the Biosorption of Cd(II) and Pb(II) from Solutions Using Siam Leaf
(Chromolaena Odorata)
by N. A. A. Babarinde, J. O. Babalola

Vol. 2. n. 1, pp. 18-24

Abstract - The biosorption of Cd(II) and Pb(II) from dilute aqueous solutions using Siam leaf (Chromolaena odorata) as the biosorbent has been studied. The biosorption study was carried out as a function of pH, contact time, initial metal ion concentration and temperature. The residual Cd(II) and Pb(II) in solution were determined using atomic absorption spectrophotometer. The FT-IR analysis of Siam leaf biomass revealed the presence of -OH, -NH and C=O. The study on pH showed that the biosorption was pH-dependent as maximum biosorption of Cd(II) was in the range pH 4-7 while that of Pb(II) was at pH 4. The biosorption was also time dependent as maximum biosorption was obtained within 60 min for each of Cd(II) and Pb(II). Kinetic studies show that the biosorption of both Cd(II) and Pb(II) can be described by pseudo-second-order kinetic model. The sorption of the two metal ions fitted well into both the Freundlich and Langmuir isotherm models. For Cd(II), the biosorption efficiency decreased while that of the Pb(II) increased with increase in initial metal ion concentration. The free energy changes obtained for the biosorption of Cd(II) and Pb(II) at 300K with an initial metal ion concentration of 100mgL^-1 are -7.084 and -8.977 kJmol^-1, respectively. The entropy changes for the biosorption of Cd(II) and Pb(II) were 141.92 and -185.95Jmol^-1K^-1, respectively. These results indicate that Siam leaf has potential for the uptake of Cd(II) and Pb(II) from industrial effluents.

Keywords: Adsorption Isotherms, Biosorption, Cd(II), Pb(II), Siam Leaf.

Usage of Pulp and Paper Secondary Sludge for Biocomposite Production: FTIR and DSC Analysis
by Maryam Edalatmanesh, Mohini Sain, Steven N. Liss

Vol. 2. n. 1, pp. 25-30

Abstract - This work studies the potential of secondary sludge from pulp and paper mills to be used as raw material for biocomposite production. To this end, a secondary sludge sample is characterized through different techniques including fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Furthermore, the cellular biopolymers of the secondary sludge are extracted and characterized. The results indicate the presence of a considerable amount of lignocellulosic substances along with cellular biopolymers in the secondary sludge. These biopolymers may be used in biocomposites as reinforcement as well as part of the polymeric matrix. Moreover, amine and amide groups identified in the extracted biopolymers, when mixed with commercial polymeric resins, can serve as molecular anchors. The thermal analysis shows that the extracted cellular biopolymers act as a homogeneous blend of polymers. This test also reveals the thermosetting nature of the extracted biopolymers resulting in the loss of their properties after being heated once. The presented results suggest that secondary sludge from pulp and paper mills may have potential applications in biocomposite production as reinforcement along with thermosetting polymeric matrices.

Keywords: Pulp and Paper Secondary Sludge, Biocomposite, Sludge Biopolymers, Differential Scanning Calorimetry.

Simultaneous Hydrodynamic and Thermal Flow Development of a Thermodependent Viscoplastic Fluid
by N. Labsi, Y. K. Benkahla, A. Boutra, E. Brunier

Vol. 2. n. 1, pp. 31-39

Abstract - Numerical analysis of simultaneously developing forced convection laminar flow and heat transfer of a viscoplastic fluid has been carried out. This fluid is incompressible and of thermodependent rheological properties. It consists on the sloe fruit juice with low pulp and pectin contents, which obeys the rheological law of Bingham and for which we adopt the Papanastasiou model to describe its behaviour. The flow takes place in an isothermal circular pipe. In order to validate the computing code, parametric computations were performed to investigate the effect of Reynolds, Prandtl and Bingham numbers on heat transfer. The effect of wall-to-inlet temperature difference on velocity and temperature profiles, Nusselt number and apparent friction factor was then analysed, by taking into account the temperature dependency of the fluid’s plastic viscosity and yield stress, for both heating and cooling situations. The results show on one hand, that the variability of the plastic viscosity provides more effect on hydrodynamic and thermal characteristics than the variability of the yield stress. On the other hand, the effect of variable plastic viscosity is more pronounced on the friction factor than on the Nusselt numbers.

Keywords: Viscoplastic Fluid, Bingham Fluid, Finite Volume Method, Forced Convection, Temperature-Dependent Rheological Properties.

   Mean Porosity and Pressure Drop Measurements in Packed Beds of Monosized Spheres: Side Wall Effects
         by A. M. Ribeiro, P. Neto, C. Pinho
         Vol. 2. n. 1, pp. 40-46

Abstract - New experimental results on the average bed porosity and pressure drop in packed beds formed by monosized spheres and with a random dense packing, are presented. A correlation for the average bed porosity was developed, based on the present porosity results and on data published by other authors, being valid for 2 < D/d_p < 17. Experimental pressure drop data for water flowing in the bed was obtained for 3 < Re_p < 379 and 3 < D/d_p < 17. These results were compared against several existing empirical correlations and models that take into account the side wall effects on pressure drop.

Keywords: Packed Beds of Spheres, Bed Porosity, Pressure Drop, Wall Effect.

Intensified Pyrolysis of Biomass in Hydrothermal Media
by K.-Q. Tran

Vol. 2. n. 1, pp. 47-51

Abstract - Pyrolysis in hydrothermal media is a promising technology for converting lignocellulosic biomass directly to liquid fuel with higher heating values and no need to reduce the water content of the original biomass. However, some aspects of the technology are not fully understood and still disputed. The reactor material constraints and difficulties coupled with the formation of unwanted products are the main challenges limiting the applications of the technology. This paper discusses the challenges and current status of possible solutions to the challenges, which is then followed by a proposal of a reaction system design suitable to overcome the challenges.

Keywords: Hydrothermal Pyrolysis, Biomass Liquefaction, Biorefinery, Biomass Gasification, Micro-Reactor, Process Intensification.

Special Section on 1st Conference on Chemical Engineering and Advanced Materials (CEAM)

Virtual forum. November 23rd - December 8th - Papers

Integrated Multiphysics Modeling in Materials and Manufacturing Processes
by J. H. Hattel

Vol. 2. n. 1, pp. 52-62

Abstract - Today, multiphysics modelling of single process steps as well as modelling of entire process sequences and the subsequent in-service conditions are areas which increasingly support optimization of manufactured parts. In the present paper two different examples of modelling manufacturing processes from the viewpoint of combined materials and process modelling are presented: i) Integrated modelling of spray forming and ii) Integrated multiphyics modelling of friction stir welding. The third example describes integrated modelling applied to a failure analysis of a premature rupture of a stellite weld on a P91 valve used in a powerplant. For all three examples, the focus is put on modelling results rather than describing the models in detail. Comparison with experimental work is given in all examples for model validation as well as relevant references to the original work.

Keywords: Integrated Modeling, Multiphysics, Spray Forming, Friction Stir Welding, Failure Analysis.

Algal Biorefinery: a Road towards Energy Independence and Sustainable Future
by Shakeel A. Khan, Rashmi

Vol. 2. n. 1, pp. 63-68

Abstract - The most important renewable resource on this planet is biomass. As the value of biomass content is related to the chemical and physical properties of large molecules, the challenges for the future are to be found in a combination of the biological, physical and chemical sciences, to replicate an oil refinery with a biorefinery thus replacing finite non-renewable fossil resources with biorenewable biomass resources for the production of food, feed, fertilizer, fuel, energy, medicinal products, industrial chemical and related consumer product through the use of clean and green bioprocess technologies. Algal biorefineries offer significant potential for future supply of oils, protein, and carbohydrates for fuels and chemicals without impacting food supplies. The residual biomass from biodiesel production processes can be used potentially as animal and fisheries feed and after anaerobic digestion can be used as fertilizers in the form of compost. Even it could solve the problem of huge carbon emission from thermal power plant by recycling the carbon. The simple, direct method of greenhouse gas (GHG) mitigation is the removal of CO2 from stack gases, followed by long term sequestration of CO2 by microalgae ponds. Thus the microalgal biodiesel projects can qualify as clean development mechanism (CDM) projects and bring in additional income through the sale of certified emission reductions (CER). Microalgal biorefinery concept could become a highly distributed source of fuel oil, energy, feed, fertilizer and medicinal metabolites and perhaps make this world pollution free and leap towards sustainable development.

Keywords: Algae, Biodiesel, Biomass, Biorefinery, Carbon Sequestration, Fuel.

Flow of Debris Formed from an Explosion-Damaged Construction
by Anna Kosinska

Vol. 2. n. 1, pp. 69-74

Abstract - In this research we focus on the propagation of a cloud of solid particles (debris) formed from an explosion-damaged construction using the tool of computer simulation. After the explosion the solid particles interact with an obstacle located at some distance after the place where the explosion occurred. The mathematical model involves the flow of the gas using standard conservation equations, and this part of the model is solved numerically. The model is used to simulate various cases where the influence of different parameters like the value of the pressure of the explosion and the particle size are investigated. The results are presented as snapshots of particle location, and also as the particle total kinetic energy during collision with the obstacle.

Keywords: Multi-Phase Flows, Particles, Process Safety.

The Effect of Carbon Dioxide on Hydrogen Embrittlement Behaviours of P110 Steel in Buffered NaCl Solution Dissolved High Contents of Hydrogen Sulfide and Carbon Dioxide
by Deng Hong-da, Li Chunfu, Cao Xianlong, Pan Changjiang

Vol. 2. n. 1, pp. 75-80

Abstract - Hydrogen embrittlement behaviours of P110 tubular steel in buffered NaCl solution dissolved mixture acid gases was investigated using constant loading test and electrochemical technique. The mixture acid gases consisted of 50%H2S/0%CO2, 50%H2S/17%CO2, 50%H2S/34%CO2, 50%H2S/50%CO2. The SEM results showed that the characteristic of fracture was hydrogen embrittlement crack in the environments containing 50%H2S with 17%CO2, 34%CO2 and 50%CO2 and without CO2. Adding 17%CO2 increased the hydrogen embrittlement susceptibility, adding 34%CO2 not distinctly affecting the susceptibility, however, adding 50%CO2 reducing comparatively the susceptibility, compared with that in 50%H2S/0%CO2,. Meanwhile, before fracture, anodic dissolution rate (ia) of P110 steel in 50%H2S/17%CO2 was higher than that in 50%H2S/0%CO2, ia in 50%H2S/34%CO2, and in 50%H2S/0%CO2 were comparatively less. Bockris’ Double layers model was applied to analyze the experimental.

Keywords: Hydrogen Emvrittlement, Low Alloy Steel, Polarization, SEM.

The Effect of Composition and Temperature on the Rheological Properties of Greases Based on Calcium Soaps
by Ancaelena Eliza Sterpu, Nicoleta Teodorescu, Iuliana Marlena Prodea, Anişoara Neagu, Anca Iuliana Dumitru

Vol. 2. n. 1, pp. 81-85

Abstract - The knowledge of the rheological properties of the greases based on calcium soaps is important because these properties ensure proper oiling of moving metallic parts of machines at high charges and in a large temperature range. In the present study, four greases has been prepared with different concentration of calcium soap:5%, 10%, 15% and 20% respectively, in paraffin oil. For viscosity determination of greases, the RHEOTHEST 2 rheoviscometer with coaxial cylinders and HAAKE VT 550 rheoviscometer with cone and plate were used. After the determination of flow curve τ = f(Ϋ), it was found that the greases had a non-newtonian behavior with respect to BINGHAM model, that meaning that the flow curve characterizing them had a linear form with a flowing threshold. Also, it was studied the variation of viscosity with temperature for grease with 20% calcium soap. It was found that increasing the temperature, the viscosity decreases having decreasing flow thresholds.

Keywords: Greases, Calcium Soaps, Rheological Properties, Rheoviscometer.

Lattice Boltzmann Computation of Plasma Jet Behaviours: Part II Argon-Azote Mixture
by R. Djebali, B. Pateyron, M. El Ganaoui, H. Sammouda

Vol. 2. n. 1, pp. 86-94

Abstract - In this paper an innovative computational approach, namely the Lattice Boltzmann Method (LBM), is used for simulating and modeling plasma jet behaviors. Plasma jets are a high temperature flows, then all physical parameters are temperature dependent. This work aims to address the issue of simulating plasma-jet from the point of view of extending the applications to simulating flows with temperature-dependent diffusion parameters (viscosity and diffusivity), focusing on the phenomena occurring in plasma-jet flow for a mixture of plasma gases, N2-Ar62.5% vol. Argon and Azote are two gases of the most ones used in plasma spraying. The mixture is used when looking for some jet properties. We limit our effort to take out the dynamic and thermal characteristics of this complex flow using the lattice Boltzmann equation. An important section focuses mainly on the validation of our results with compute jet dynamics software such as GENMIX and Jets&Poudres developed in laboratory SPCTS in several updated edition. These codes established for many turbulence models (k-epsilon, k-omega, Prandtl's models…) are helpful numerical keys for understanding the physics of plasma jets and plasma spraying. Our numerical results based on the centerline temperature and velocity profiles, its distributions over the computational domain, the gaussian radial profiles and the effects of inlet quantities are analyzed. The quality of the results shows a great efficiency for the lattice Boltzmann method.

Keywords: Lattice Boltzmann Method, Modeling and Simulation, Plasma Jet.

The Effect of Vane Angle on the Mist Eliminator Efficiency
by E. Narimani, Sh. Shahhoseini

Vol. 2. n. 1, pp. 95-98

Abstract - One of the most effective devices to separate liquid from the gas is a vane mist eliminator. Liquid separation efficiency in this equipment is largely dependent on the gas velocity and geometrical parameters. However, the upper limit of gas throughput is restricted by the re-entrainment of the deposited liquid from the separator surfaces into the gas stream. In this study the effects of different vane angles on the efficiency of this type of mist eliminator have been investigated, using computational fluid dynamics (CFD). Eulerian-Lagrangian approach has been applied. Simulation results showed there is a conceivable dependency of separation efficiency and vane geometry.

Keywords: Wave-Plate Mist Eliminators, CFD, Separation Efficiency, Eulerian–Lagrangian Approach- Angle- Vane Spacing.

BEA and FAU Type Zeolites in Phenol Removal from Wastewaters: Effect of Hydrophobicity
by Arsène H. Yonli, Isabelle Gener-Batonneau, Samuel Mignard

Vol. 2. n. 1, pp. 99-102

Abstract - The present work deals with the removal of phenol from water contaminated in laboratory by phenol. BEA postreated and siliceous samples and HY samples with varying acidities and porous structures were used to study the removal of phenol in water. The results show that if for HY samples the phenol uptake can be predicted by knowing the Brønsted acidity of the samples, the Brønsted acidity was not sufficient to predict phenol adsorption capacity over BEA samples. Moreover among the studied zeolites the siliceous BEA was the most efficient for the removal of phenol in water because of a high value of HI.

Keywords: Phenol, Synthetic Zeolites, Adsorption, Hydrophobicity Index.

Dynamic Simulation of a Proton Exchange Membrane Fuel Cell
by A. Sanchez, A. Cancela, S. Urrejola, R. Maceiras, P. Rodriguez

Vol. 2. n. 1, pp. 103-106

Abstract - The objective of the present work is to create a mathematical model, build a simulation of a proton exchange membrane fuel cell (PEMFC), using the Simulink® package, included in Matlab software. The purpose of the model is to facilitate the knowledge of the operation parameters of the system, saving resources and time in a previous stage to the operation with real systems. The behaviour of the model was test with a real fuel cell.

Keywords: Fuel Cell, Hydrogen, Mathematical Model, PEMFC, Simulation.

Influence of Fuel Oxygen on Diesel Combustion, Engine Performance, Ultrafine Particles, THC, CO, Smoke and NOx Emissions
by Md. Nurun Nabi, Rudolf Schmid, Dhandapani Kannan, Johan Einar Hustad

Vol. 2. n. 1, pp. 107-114

Abstract - This paper reports on diesel combustion and emissions with neat European auto diesel fuel and diesel-oxygenate blends. 5 and 10 vol%, respectively of an oxygenate, diethylene glycol dimethyl ether (DGM) were blended with diesel fuel (DF). The fuels were characterized by gas chromatography and infrared spectroscopy. The combustion experiment was conducted with a six-cylinder, four-stroke, turbocharged, direct injection (DI) diesel engine. The experimental results showed that without deteriorating engine performance, smoke, total unburnt hydrocarbon (THC) and carbon monoxide (CO) emissions were reduced significantly, while oxides of nitrogen (NOx) emissions were increased slightly with the DF95 fuel (diesel fuel 95 vol% and oxygenate 5 vol%) and DF90 (diesel fuel 90 vol% and oxygenate 10 vol%) fuel. Investigation of ultrafine particles with the DF95 and DF90 fuels was one of the major targets in this work, showed remarkable reduction when compared with neat diesel fuel (DF100).

Keywords: Oxygenate, Diesel Combustion, Engine Performance Ultrafine Particles, Emissions.

The Evaluation of the Secondary Ulexite Mineral as a Neutron Shielding Material
by A. S. Kıpçak, E. M. Derun, N. Tuğrul, M. B. Pişkin

Vol. 2. n. 1, pp. 115-122

Abstract - Turkey has the largest borax, ulexite and colemanite reserves in the world. All the countries are dependent upon colemanite and ulexite reserves of Turkey. In this study depending on the ability of neutron absorption of secondary ulexite mineral, the structural and physical properties are examined. Firstly, the sieve analysis of secondary ulexite mineral is made then four different particle sizes of secondary ulexite minerals are selected, prepared and X-Ray Diffraction of secondary ulexite minerals is made for structural analysis. After that, B2O3 contents of secondary ulexite minerals are analyzed experimentally. After these examinations X-Ray Florescence analysis is made for the determination of Zn, and Fe and Ar contents. Thermal analysis of secondary ulexite minerals is performed for obtaining the energy and weight changes with temperature. For this aim, the method of Differential Thermal Analysis and Thermal Gravimetry is used. Afterwards, secondary ulexite mineral is tested in the Howitzer equipment for the nuclear absorption and confront with the colemanite mineral that is mostly used in the experiments at this field of study.

Keywords: Secondary Ulexite, Colemanite, Neutron Absorption, Neutron Permeability.

Kinetics Study of CO₂ Capturing as Hydrate in Saline Water
by M. Sarshar, J. Fathikaljahi

Vol. 2. n. 1, pp. 123-128

Abstract - Global warming and green house effects are two main results of increasing CO₂ concentration in the atmosphere. Some novel methods must be developed for capturing carbon dioxide in the form of permanent reservoirs to balance its atmospheric concentration. Stabilizing CO₂ concentration in the atmosphere is vital because of the increasing rate of using fossil fuels in the industries and heating purposes. Therefore, reducing the concentration and storing CO₂ away from the atmosphere is a challenging subject for the scientists.
CO₂ hydrate is formed at 3.0-4.4 MPa and 0-5°C at a 3 liters semi batch reactor in the presence of distilled, hard and saline waters. CO₂ consumption versus time is measured in fifteen experiments for studying the kinetics of hydrate formation. In all experiments, three stages of hydrate formation are distinguished by the slope of the CO₂ content curve of the storage tank. First stage with gradual slope recognizes dissolution of CO₂ and nucleation periods of the hydrate crystallization. Second stage with the sharp slope recognizes hydrate growth and third stage with constant or declined slop indicates the end of hydrate crystallization.

Keywords: Batch Reactor, Capture, CO₂ Hydrate, Kinetics, Sequestration.

   Innovative System to Treat Winery Wastewater: Mathematical Modeling
          by Rosa A. Rodriguez, Marcelo E. Echegaray, Gustavo Muñoz, Miguel Navas, Stella M. Udaquiola
          Vol. 2. n. 1, pp. 129-133

Abstract - In this work, a secondary alternative treatment for the wastewater depuration of the winery industry was evaluated. In order to determine their efficiency, OCD was chosen as reference parameter. The experimental work was carried out in a tubular reactor constituted by a fixed bed of grains, where the influence of different particles size and effluent flows e to try was analyzed. A decrease of OCD value was observed (between the 16 and 54%). Better decrease percentages of this parameter were obtained working with slow effluents flows to try and with a bed constituted by small particles too. Later, a mathematical model was developed, analyzing different kinetic of the purification process according to the experimental obtained values. As a result of this analysis, a good approach of the experimental values was obtained using a kinetics order equal to six.

Keywords: Secondary Treatment, Winery Effluents, OCD, Mathematical Model.

   A Proposal of Portable Equipment for Pretreatment in Chemical Analysis
          by L. M. Silva, R. R. Lima, E. W. Simões, M. L. P. da Silva
          Vol. 2. n. 1, pp. 134-141

Abstract - This work evaluates an array of miniaturized structures with practical applications in pretreatment or for Chemical Analysis. Such devices are manufactured with acrylic or stainless steel and they can be easily disassembled. They also allow particle removal, spray formation, heating and coarse separation of volatile organic compounds (VOCs) mixtures. The low-cost and small-sized system showed promising performance for a number of technological applications.

Keywords: Chemical Analysis, Equipment, Miniaturization, Simulations and VOCs.

   The Use of Redox Mediators for Enhancing the Decolourisation of Orange G in a Sequencing Batch Reactor (SBR)
          by M. Mehrdad, B. Bonakdarpour, B. Nasernejad
          Vol. 2. n. 1, pp. 142-145

Abstract - The declorization of the acid azo dye, Orange G (Acid Orange 10) in an anaerobic phase of the anaerobic-aerobic sequencing batch reactor feed by synthetic wastewater was investigated. Moreover, the impact of a redox mediator (AQS) on the color removal was studied. it is for the first time that the decolorization of Orange G is investigated in SBR system with activated sludge. The redox mediator was really effective for cleavage the azo band and increased the efficiency of the reactor. When 20 mg/l of Orange G was added to the sysnthetic wastewater, the decolorization efficiency was 50 % without the addition of AQS. The decolorization efficiency increased up to 75% when the small quantity of AQS, 0.05nM, was added to the wastewater. The high COD removal of synthetic dye wastewater was observed during the operation. The COD removal was always in the range of 80-90 %.

Keywords: Activated sludge, Azo dye, Biodegradation, SBR.

   Influence of Intermittent Loading on the Removal of High Concentrations of VOCs in a Biofilter
          by S. M. Zamir, R. Halladj, M. Ferdowsi
         Vol. 2. n. 1, pp. 146-149

Abstract - In this research, the elimination of a mixture of toluene and hexane vapors from waste air was studied in a compost biofilter under intermittent condition. The system was operated 10 h a day on the air residence times 0.9, 1.5 and 3 min and 2-3.8 gm-3 of pollutant concentration. Regarding the harsh biological condition of biofilter media such as high pollutant concentration and daily intermittent aeration, reaching the steady-state situation and removal efficiency of 90% lasted about 44 days.

Keywords: Biofilter, Compost, Intermittent loading, VOC.

   Inhomogeneous Magnetic Field Effects on the Hydrodynamic Properties of Multiphase Catalytic Reactors
          by Mugurel C. Munteanu, Faïçal Larachi
         Vol. 2. n. 1, pp. 150-154

Abstract - An external inhomogeneous magnetic field is able to vary the gravity conditions for both diamagnetic and paramagnetic materials via the Kelvin magnetization body force density. The Kelvin body force vector can be co-linear or antiparallel to the magnetic field vector depending on material magnetic susceptibility, magnetic field gradient and direction of magnetic field. In chemical reaction engineering, magnetic fields may open up unanticipated perspectives in the upgrading of chemical processes. In multiphase catalytic systems, a number of factors need be optimized to improve processes efficiency, for example, catalyst wetting efficiency, liquid holdup and pressure gradient in gas-liquid flows through porous media. Magnetic-field aided flows thus contribute to improve wetting efficiency, a key factor in several catalytic applications in trickle flow partially wetted beds. In this contribution, we will show new experimental data on trickle and flooded bed operations in terms of hydrodynamic response when these systems experience either hypogravity or hypergravity controlled via inhomogeneous magnetic fields. Liquid holdup, pressure drop and wetting efficiency were measured in the absence and in the presence of inhomogeneous magnetic field and comparisons were performed.

Keywords: Microgravity, Packed-Bed Reactor, Hydrodynamic Properties.

   MDDSS: a New Software for Multicomponent Distillation Design and Simulation
          by Mohanad El-Harbawi, Anthony Marc Botha
          Vol. 2. n. 1, pp. 155-160

Abstract - The framework of developing a Multicomponent Distillation Design and Simulation Software (MDDSS) using Visual Basic programming language is presented in this paper. This software is able to perform product prediction and column design of a multicomponent distillation system when desired fields are entered into the software. The software utilized the method of Fenske-Underwood-Gilliland (FUG) to determine the minimum number of stages, composition of products minimum reflux, number of stages, feedpoint location, height and diameter of the column. The software can be used to optimise and design multicomponent distillation towers by avoiding tedious manual calculations where the probability of making mistakes is high, therefore, one will be able to achieve the maximization of saleable product yields at lower costs. Moreover, the MDDSS application is capable to work as a stand alone application. This implies that even though the software was created in Visual Basic, it will not need Visual Basic to be used on the user’s PC. The software is compatible with all windows operating systems. The cost of developing the software is fairly cheap. The results generated by the software are validated and verified by comparing the results with a commercial simulation software (HYSYS) and published literature and manual calculations.

Keywords: Multicomponent Distillation, Simulation, Visual Basic, HYSYS.

   New Method to Simulation of a Vacuum Distillation Unit in the Refining Process of Oil and the Reducing of the
Vacuum Residue Generation
          by Rodolfo B. Vadinal, Maria R. W. Maciel
          Vol. 2. n. 1, pp. 161-166

Abstract - More and more oil refineries need to process heavier oils, despite all the difficulties in processing. Generally the refineries have two distillation units: the atmospheric distillation unit (ADU) and the vacuum distillation unit (VDU), responsible by retrieving the heavier oil fractions. The ADU has been the subject of many studies and it has good computational models to its representation. On the other hand, the VDU has not been studied in depth and it does not have good representations in the process simulators. Therefore, using the process simulator Aspen Plus, we attempted to create a new methodology to simulate the VDU, through 04 separate towers, one for each area of production’s withdrawal [vacuum residue (VR), slop wax, heavy vacuum gasoil (HVGO) and light vacuum gasoil (LVGO)]. Two different atmospheric residues (ATR16 and ATR19) were considered in this study to test the proposed method and perform a sensitivity analysis of the unit, to identify operational variable that provides a lower generation of VR. The study revealed that the reduction of the pumparound temperature of HVGO section of 245°C to 220°C reduced 16.2% (ATR16) and 12.9% (ATR19) in the VR generation and it improves the HVGO recovery in 34.1% (ATR16) and 56.0% (ATR19).

Keywords: Vacuum Distillation, Computer Simulation, Petroleum.

   A Comparison between the Predictions of Sequencing Batch Reactor (SBR) Models with Generalized Regression and Dynamic
Neural Networks
          by Moein Navvab Kashani, Shahrokh Shahhosseini
        Vol. 2. n. 1, pp. 167-173

Abstract - Sequencing batch reactor (SBR) is a bioreactor, based on activated sludge and operates on a sequence of fill and draws cycles, to treat the high strength wastewater. SBR process is complex and attains a high degree of nonlinearity due to time dependency of chemical and biochemical reactions and the presence of bioorganic constituents that are difficult to model using mechanistic approaches. This study, presents two class of artificial neural networks (ANN) model for SBR. The first category of introduced neural network was dynamic neural networks (DNN). In addition to that, a generalized regression neural network (GRNN) model of SBR process is the second class that has been developed based on the radial basis function (RBF) approach. Eventually, the resulted of DNN and GRNN models were compared to the experimental data. This comparison beside the adequate regression between the network outputs and the experimental data (more than 0.94), revealed that the GRNN SBR model was much more accurate than DNN model. Furthermore, the GRNN models with the preprocessed input data based on the multiway principal components analysis (MPCA) are more precise than the models with the raw data, causing its predictions to be very close to the experimental data.

Keywords: DNN, GRNN, Neural Network, MPCA, Sequencing Batch Reactor (SBR).

   Diffusion in Isothermal Ternary Gas Mixtures
          by G. A. Akylbekova, V. N. Kossov, I. V. Poyarkov, Yu. I. Zhavrin
            Vol. 2. n. 1, pp. 174-177

Abstract - It is experimentally shown that if there are more than two components in the gas mixture, the system becomes instable even when the density of mixture is lower in upper part than in the bottom. The transition from the diffusion to the convective mixing is possible by the certain values of the pressure, the temperature, the viscosity and geometrical characteristics of the vessel. Some three-component gas mixtures are characterized by the atypical concentrational distribution of the system components during the convection, which is caused by the difference of diffusion coefficients. The existence of structural formations at this process was shown by Tepler's shadow method. The linear analyses of stability can explain reasons of this «paradox of stability». The were found the following novel effects in isothermal three-component gas mixtures with steady stratification of density of the gas mixture: there are observed the curves with two maximums on a number of mixtures at variation of the channel diameter; there are registered some transitions from diffusion to convection and back at measurement of composition of mixture not only at the first stage of mixing, but also on the subsequent ones. The theoretical results are compared with experimental findings of stability border in three-component gas systems.

Keywords: Diffusion, Instability of Mechanical Equilibrium, Isothermal Multicomponent Gas Mixtures, Theory of Stability, Partial Rayleigh Numbers.

   Stochastic Analysis in the Visco-Elastic Impact Condition
          by L. Hou, H. L. Li, H. Wang, L. Qiu
           Vol. 2. n. 1, pp. 178-183

Abstract - People are interested in the properties of visco-elastic material in various impact conditions,but the research is difficult, especially in the auto-crash safety engineering process. In this paper an application of boundary-layer computing for the non-Newtonian rate type impact hardening and share thinning phenomenon are discussed. Also the posteriori estimate solver and asymptotic analysis have been used for the sensitive pre-stage deformation before the impact happening. The numerical scheme yields the convergent finite element analysis (FEA) solution and stable semi-discrete Galerkin-Runge-Kutta(G-RK) iteration.We use the high performance computing (HPC) tool to carry out the research on the passive safety analysis with engineering computing.

Keywords: Stochastic Analysis, Boundary-Layer, FEM.

   Chemical Modification of Carbon Blacks with Maleic Acid in Different Solvents
          by Vijayshankar Asokan, Pawel Kosinski, Velaug Myrseth Oltedal
          Vol. 2. n. 1, pp. 184-187

Abstract - Carbon blacks easily functionalized using di-carboxylic acid. In this work, maleic acid is used and it seems simple and effective. Four different carbon black samples and two different solvents were used for functionalization. The investigations using TGA and XRD indicate that maleic acid modification creates functional groups on the surface of carbon materials, but functional groups vary with the solvent.

Keywords: Carbon Black, Functionalization of Carbon, Maleic Acid.

   Solid-State Synthesis of Sodium Metaborate for Hydrogen Storage Application
          by Aysel Kanturk Figen, Sabriye Piskin
         Vol. 2. n. 1, pp. 188-191

Abstract - Sodium borohydride (NaBH4), which is known reducing agent, has attracted more attention as an anodic fuel in a fuel cell or as a hydrogen storage medium due to its high hydrogen storage capability (10.6 wt %). According to the several publications, anhydrous sodium metaborate (NaBO2) are used as starting material in hydrogen storage in form of NaBH4. When the production technologies of NaBH4 based on NaBO2 are investigated, it is seen that NaBO2 becomes quite essential in commercial borates class and hydrogen storage application. Generally, hydride NaBO2 is synthesized based on hydrothermal method. To be used in NaBH4 production, it is necessary to performed calcinations step after the synthesis reaction. In the present study, anhydrous NaBO2 was synthesized based on solid-state reaction. Product was characterized by XRD and FT-IR techniques to identify crystal phase and chemical structure. It is concluded that, solid-state synthesis is applicable method for anhydrous NaBO2 production. The main advantage of this technique, the calculation step is eliminated to prepare anhydrous NaBO2 for hydrogen storage application.

Keywords: Sodium Metaborate, Solid-State, Sodium Borohydride, Hydrogen Storage.

   Fast Template-Free Synthesis of Flower-Like Cobalt Nanostructures
          by K. Shojaee, N. Fallah, Z. Khalili, E. Mofarrah
          Vol. 2. n. 1, pp. 192-197

Abstract - In this research, a new method for template-free synthesis flower-like cobalt nanostructures under microwave radiation is presented. The required time (under ten minutes) for complete synthesis of cobalt nanostructures is the most distinguishing advantage of this method. No templates for self-assembly were used in this method. The structural characteristics, size distributions, and shape of the products were investigated using X-Ray Diffraction, Dynamic Laser Light scattering, and Scanning Electron Microscopy instruments, respectively. The hysteresis curve of the cobalt nanostructures was specified by Vibrating Sample Magneometry technique. The functional groups occupying the nanostructures surfaces were also determined by a Fourier Transform Infra Red instrument.

Keywords: Cobalt, Ethylene glycol to Water Ratio, DLLS, Flower-Like Nanostructures, OH¯ Ions.

   A Kinetic Study of Kurnakovite Dehydration: Coats-Redfern Model and Kinetic Compensation Effect
          by H. Eren Figen, Sabriye Piskin
          Vol. 2. n. 1, pp. 198-202

Abstract - Thermal analysis techniques widely use to calculate kinetic parameters of solid-state reactions. Especially, thermogravimetric data related with thermal properties of the sample which is detected of mass change according to the temperature variation. Different kinetic model applied to calculate the kinetic parameters. The aim of this study is to determine the dehydration kinetic parameters (reaction order, activation energy, Arrhenius constant) of kurnakovite mineral by using Coats-Redfern non-isothermal kinetic model. The velocity equitation of dehydration reaction was formulated according to kinetic parameters. Thermal analyses were carried out at different heating rates of 2, 5 and 10 °C/min in a pure nitrogen gas (200 ml/min) in the temperature range of 30–800°C. The Kinetic Compensation Effect (KCE) equation is formulated to validate kinetic data obtained from different heating rates. This equation shows a linear correlation between Activation Energy (Ea) and Arrhenius Constant (k0).

Keywords: Kurnakovite, Dehydration Kinetic, Coats-Redfern, Kinetic Compensation Effect, Thermogravimetry.

   Computer Modeling of Microporous Materials (Book Review)
          reviewed by Ivan Gospodinov
          Vol. 2. n. 1, pp. 203

In recent years computer modelling has achieved major advances in material science and many other scientific fields. This book is an excellent contemporary overview of modeling techniques in the science of microporous materials (e.g. zeolites, aluminophosphates, etc). It provides a survey of the state-of-the-art in modeling on microscopic level – that of atoms and molecules. Two broad types of atomistic simulations are reviewed. The first class of methods relies on the use of interatomic potential functions to calculate structures and energies employing simulation methods such as Monte Carlo and molecular dynamics. The second class of methods solve the Schrodinger equation at some level of approximation to model processes such as bond breaking and making in catalytic reactions.
The book is edited by three eminent experts in the field of molecular simulation. It provides a comprehensive review of key recent developments in modelling of microporous materials, among them :
The first chapter: Static lattice modelling and structure prediction of micro- and mesoporous materials, C. R. A. Catlow, R. G. Bell, B. Slater, updates on the field of static lattice techniques employing interatomic potentials, both to model long-range, local and surface structures of micro- and mesoporous systems, and to study energetics and stabilities. The chapter highlights recent developments in predictive structural modelling and the new and exciting field of simulations of zeolite surfaces.
The next three chapters are:
Chapter 2. Adsorption phenomena in microporous materials by B. Smit.
Chapter 3. Dynamics of sorbed molecules in zeolites by S. M. Auerbach, F. Jousse, D. P. Vercauteren.
Chapter 4. Dynamic Monte Carlo simulations of diffusion and reactions in zeolites by F. J. Keil, M.-O. Coppens.
They focus on the modelling of sorbed molecules in zeolites. Chapter 2 describes the state-of-the-art of Monte Carlo methods in simulating sorption isotherms. Molecular dynamics simulations of sorbate diffusion are reviewed in Chapter 3, while Chapter 4 focuses on the growing applications of dynamical Monte Carlo methods to molecular transport in microporous solids.
Application of quantum mechanical methods are provided in Chapters 5 through 7.
Chapter 5. Planewave pseudopotential modelling studies of zeolites by J. D. Gale.
Chapter 6. Reaction mechanisms in protonic zeolites by X. Rozanska, R. A. van Santen.
Chapter 7. Structure and reactivity of metal ion species in high-silica zeolites by G. M. Zhidomirov, A .A. Shubin, R. A. van Santen.
Different techniques and applications, are reviewed, including both periodic and cluster methods, with the main emphasis being on techniques based on density functional theory. Chapter 5 focuses on applications employing periodic methods. In Chapter 6, the emphasis is on catalysis effected by acid sites; while Chapter 7 describes applications to catalytic processes in which the active sites are metal ions.
Chapter 8 (Chapter 8. Template–host interaction and template design by D. W. Lewis) focuses on use of modelling methods in understanding zeolite synthesis, in particular relating to the role of organic templates.
Chapter 9 The interplay of simulation and experiment in zeolite science (by C. Freeman and J.-R. Hill) closes in excellent way the collection of chapters.