An-Najah Blogs :: Nashaat N. Nassar An-Najah Blogs :: Nashaat N. Nassar en-us Wed, 26 Feb 2020 22:06:56 IST Wed, 26 Feb 2020 22:06:56 IST Nanoparticle Uptake by (W/O) Microemulsions Articleshttp:booksgooglecombooks?id=oR5_SSWMmJkCpg=PA465lpg=PA465dq=22NashaatNNassar22source=blots=8BIzjFyprlsig=j65I1VtdtxVcSLURmspeUnXY2uchl=enei=Gai3SfzdDpm1jAfa54GwCQsa=Xoi=book_resultresnum=6ct=resultPPA465M1Removal of Asphaltenes from Heavy Oil by Nickel Nano and Micro Particle Adsorbents ArticlesIn this work nickel nano and micro particle adsorbents were employed for removing asphaltenes from heavy oil model solution by adsorption The approach comprises the following: dispersing nickel particles into heavy oil matrixes and relying on the surface activity of asphaltene molecules attract them onto the surface of the nickel particles Nickel particles were chosen due to their potential application as catalysts in heavy oil upgrading The adsorption was investigated by adding nickel particles with different sizes from 100 nm to 3 m to model solutions of heavy oil consisting of asphaltenes in toluene After shaking the suspension for specific times the particles with adsorbed asphaltene molecules were separated by centrifuge Adsorption kinetics and isotherms were constructed using UV-Vis spectrophotometry The effect of contact time initial asphaltene concentration particle size and mass of nickel particles were evaluated using batch kinetic runs Using 10 g of particles per liter of model solution equilibrium was approached in nearly 25 h within which over 85 of the asphaltenes in the original solution were removed Asphaltene adsorption capacity onto nickel nanoparticles compared favorably with nickel micro particles Higher percent removal was achieved when higher mass of nanoparticles was employed The adsorption isotherms showed a maximum in both cases nickel nano and micro particles which did not follow Langmuir or Freundlich typesNanoparticle Preparation Using the Single Microemulsions Scheme ArticlesNanoparticles serve the need for advanced materials with specific chemical physical and electronic properties These properties can be attained by manipulating the particle size Consequently size control has been recognized as a key factor for selecting a nanoparticle preparation technique wo Microemulsions or reverse micelles have been successfully used to prepare wide variety of nanoparticles with controlled sizes Studies showed that adjusting microemulsion andor operation variables provides a key to controlling nanoparticle size and polydispersity The effect of a given variable however relies heavily on the reactant addition scheme The mixing of two microemulsions scheme has been widely used in the literature and the effect of microemulsion and operation variables on intermicellar nucleation and growth was detailed The single microemulsions reactant addition scheme on the other hand enables intramicellar nucleation and growth and therefore may lead to a different response Moreover studies on nanoparticle preparation using the single microemulsions scheme involved more of reactive surfactants and introduced the concept nanoparticle uptake which pertains to the maximum colloidal concentration of nanoparticles that can be stabilized in a microemulsion system This review looks into the mechanisms controlling nanoparticle formation and compares literature trends reported for the effect of microemulsion and operation variables on the nanoparticle size and polydispersity for the single microemulsions reactant addition scheme Moreover it sheds some light on nanoparticle uptake and its significanceEffect of microemulsion variables on copper oxide nanoparticle uptake by AOT microemulsions ArticlesUltradispersed metal oxide nanoparticles have applications as heterogeneous catalysts for organic reactions Their catalytic activity depends primarily on their surface area which in turn is dictated by their size colloidal concentration and stability This work presents a microemulsion approach for in situ preparation of ultradispersed copper oxide nanoparticles and discusses the effect of different microemulsion variables on their stability and highest possible time-invariant colloidal concentration nanoparticle uptake In addition a model which describes the effect of the relevant variables on the nanoparticle uptake is evaluated The preparation technique involved solubilizing CuCl2 in single microemulsions followed by direct addition of NaOH Upon addition of NaOH copper hydroxide nanoparticles stabilized in the water pools formed in addition to a bulk copper hydroxide precipitate at the bottom The copper hydroxide nanoparticles transformed with time into copper oxide After reaching a time-independent concentration mixing had limited effect on the nanoparticle uptake and particle size Particle size increased with increasing the surfactant concentration concentration of the precursor salt and water to surfactant mol ratio; while the nanoparticle uptake increased linearly with the surfactant concentration displayed an optimum with R and a power function with the concentration of the precursor salt Surface areas per gram of nanoparticles were much higher than literature values Even though lower area per gram of nanoparticles was obtained at higher uptake higher surface area per unit volume of the reverse micellar system was attained A model based on water uptake by Wisor type II microemulsions and previously used to describe iron oxide nanoparticle uptake by the same microemulsions agreed well with the experimental results Solid olive waste in environmental cleanup: Oil recovery and carbon production for water purification ArticlesA potentially-economic three-fold strategy to use solid olive wastes in water purification is presented Firstly oil remaining in solid waste higher than 5 of waste was recovered by the Soxhlet extraction technique which can be useful for the soap industry Secondly the remaining solid was processed to yield relatively high-surface area active carbon AC Thirdly the resulting carbon was employed to reversibly adsorb chromate ions from water aiming to establish a water purification process with reusable AC The technique used here enabled oil recovery together with the production of a clean solid suitable for making AC This process also has the advantage of low production costStudy and Modeling of Iron Hydroxide Nanoparticle Uptake by AOT (w/o) Microemulsions ArticlesControl over nanoparticle size is a key factor which labels a given preparation technique successful When organic reactions are mediated by ultradispersed catalysts the concentration of the colloidal nanoparticle catalysts and their stability become key factors as well In this study variables affecting iron hydroxide nanoparticle size stability and maximum possible colloidal concentration in AOTwaterisooctane microemulsions were investigated Iron hydroxide was prepared in single microemulsions by first solubilizing iron chloride powder in the water pools followed by addition of aqueous NaOH Upon addition of NaOH FeOH3 nanoparticles stabilized in the water pools formed in addition to bulk precipitate of FeOH3 The time-invariant concentration of the stabilized FeOH3 is defined as the nanoparticle uptake and it corresponds to the maximum possible concentration of the colloidal nanoparticles The effect of the following variables on the nanoparticle uptake and size distribution was investigated: mixing time; surfactant concentration; water to surfactant mole ratio; and the initial concentration of the precursor salt At 300 rpm of mixing a constant uptake of iron hydroxide nanoparticles was achieved in about 2 h and further mixing had limited effect on the nanoparticle uptake and particle size An optimum R was found for which a maximum nanoparticle uptake was obtained Nanoparticle uptake increased linearly with the surfactant concentration and displayed a power function with the initial concentrations of the precursor salt The surface areag of the nanoparticles was much higher than literature values however following a trend opposite to that of the nanoparticle uptake The surface areaunit volume of the microemulsion on the other hand followed the same trend as the nanoparticle uptake The particle size increased as R andor the surfactant concentration increased A mathematical model based on correlations for water uptake by Winsor type II microemulsions accurately accounted for the effect of the aforementioned variables on the nanoparticle uptakePreparation of iron oxide nanoparticles from FeCl3 solid powder using microemulsions ArticlesNanoparticles of iron oxide were prepared by subjecting iron chloride powder to wo microemulsions consisting of sodium bis2-ethylhexyl sulfosuccinate AOT isooctane and water FeCl3 was first dissolved in the water pools of the microemulsion and then reacted with NaOH added as an aqueous solution to form iron oxide The amount of NaOH solution was limited so that single microemulsion phase is obtained This technique serves as an in-situ nanoparticle preparation technique aimed at minimizing particle aggregation associated with particle transportation to required sites In this study the effects of AOT concentration and water to AOT mole ratio on the nanoparticle size were investigated UVVis spectrophotometry and transmission electron microscopy TEM were used to measure the particle size distributionMelt Intercalation in Montmorillonite/Polystyrene Nanocomposites ArticlesAtactic polystyrene PS was used to study the effect of flow field shear andor elongational on the intercalation of polymer clay nanocomposites PNC Three grades of PS with different molecular weights were compounded with an ammonium-modified montmorillonite Cloisite 10A in a twin-screw extruder TSE The compounds were subsequently fed to a single screw extruder fitted with one of three specially designed torpedo-attachments The attachments were designed to provide combinations of different levels of shear and elongational deformations The resins TSE compounds and final PNCs were characterized for the degree of intercalation degradation rheological behavior and mechanical properties The data showed that the thermal decomposition of the quaternary ammonium intercalant caused severe damage to both PNC components: a collapse of the organoclay interlayer spacing and the thermo-oxidative degradation of PS In spite of these detrimental effects the attachment employing combined elongational and shear flow resulted in generally larger gallery spacing and more improvement of the mechanical properties than the other two attachments