- Tuesday, January 1, 2008
- Published at:Microemulsions
- http://books.google.com/books?id=oR5_SSWMmJkC&pg=PA465&lpg=PA465&dq=%22Nashaat+N.+Nassar%22&source=bl&ots=8BIzjFyprl&sig=j65I1VtdtxVcSLURmspeUnXY2uc&hl=en&ei=Gai3SfzdDpm1jAfa54GwCQ&sa=X&oi=book_result&resnum=6&ct=result#PPA465,M1
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- Tuesday, January 1, 2008
- Published at:Proceeding (615) Nanotechnology and Applications - 2008
- In 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 μm), 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
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- Tuesday, January 1, 2008
- Published at:Current Nanoscience, Volume 4, Number 4, November 2008 , pp. 370-380(11)
- Nanoparticles 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. (w/o) Microemulsions, or reverse micelles, have been successfully used to prepare wide variety of nanoparticles with controlled sizes. Studies showed that adjusting microemulsion and/or 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, s
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- Saturday, December 1, 2007
- Published at:Journal of Colloid and Interface Science, Volume 316, Issue 2, 15 December 2007, Pages 442-450
- Ultradispersed 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-indep
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- Sunday, July 1, 2007
- Published at:Journal of Environmental Management, Volume 84, Issue 1, July 2007, Pages 83-92
- A 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 cost.
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