Jaber Ebne Hayyan Research Laboratory

Tehrān, Iran

Jaber Ebne Hayyan Research Laboratory

Tehrān, Iran
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Outokesh M.,Sharif University of Technology | Hosseinpour M.,Sharif University of Technology | Ahmadi S.J.,Sharif University of Technology | Mousavand T.,McGill University | And 3 more authors.
Industrial and Engineering Chemistry Research | Year: 2011

Hydrothermal synthesis of CuO nanoparticles under near-critical and supercritical conditions was investigated from two different standpoints in the current study. The first standpoint was optimization of "yield", "purity", and "size of the nanoparticles" that were optimized at T = 500 °C, time = 2 h, [Cu(NO3)2] = 0.1 mol dm-3, and pH 3. This was achieved by undertaking an orthogonal experiment design methodology and performing different instrumental analyses, such as X-ray diffractometry, inductively coupled plasma spectrometry, and transmission electron microscopy, along with treatment of the data by analysis of variance (ANOVA). The second goal of the study was elucidation of the mechanisms of effects of operational conditions (e.g., temperature) on the above-mentioned target parameters, through application of the appropriate mechanisms of formation of nanoparticles. Nanoparticles are suggested to form initially in the liquid phase as Cu(OH)2, which are later transformed to Cu2(OH)3NO3, through which CuO product is obtained. Decomposition of nitric acid also plays role in this mechanism. Fabricated nanoparticles are effective catalysts for the synthesis of benzoheterocycle compounds in the pharmaceutical industries. © 2011 American Chemical Society.


Hosseinpour M.,Sharif University of Technology | Ahmadi S.J.,Jaber Ebne Hayyan Research Laboratory | Mousavand T.,McGill University | Outokesh M.,Sharif University of Technology
Journal of Materials Research | Year: 2010

Ultra fine CuO nanoparticles In the range of 2 ± 0.2 nm were synthesized by the supercritical hiydrotliermal method in a batch reactor. Itwas demonstrated that elevating the pH of the Cu2+ precursor solution to around 6 (neutral condition) not only does not lead to excessive agglomeration of the particles, but also reduces particle size and in general promotes their nanoscale characteristics. Prepared nanoparticles were immobilized in the biopolymcric matrix of barium alginate and calcined at different temperatures resulting in micro spherical granules of high porosity and elevated mechanical strength. The fabricated samples were characterized using x-ray diffractometry (XRD), transmission and scanning electron microscopy (TEM and SEM), nitrogen adsorption analysis (BET), mechanical testing,and temperature programmed reduction (TPR). It was found that topochemical models based on a nucleation growth mechanism fail in proper fitting of theTPR data. Instead, a generalized Sestak model in which different physicochemical mechanisms such as the mass action law are taken Into account gives asatisfactory regression of the kinetics behavior. © 2010 Materials Research Society.


Ahmadi S.J.,Jaber Ebne Hayyan Research Laboratory | Outokesh M.,Sharif University of Technology | Hosseinpour M.,Sharif University of Technology | Mousavand T.,McGill University
Particuology | Year: 2011

A simple and efficient method was developed for fabricating spherical granules of CuO catalyst via a three-step procedure. In the first step, copper oxide nanoparticles were synthesized by hydrothermal decomposition of copper nitrate solution under supercritical condition. Then, they were immobilized in the polymeric matrix of calcium alginate, and followed by high-temperature calcination in an air stream as the third step, in which carbonaceous materials were oxidized, to result in a pebble-type catalyst of high porosity. The produced CuO nanoparticles were characterized by transmission electron microscopy (TEM) that revealed an average size of 5 nm, X-ray diffractometry (XRD), and thermo gravimetric (TG) analysis. The catalysts were further investigated by BET test for measurement of their surface area, and by temperature-programmed reduction analysis (H2-TPR) for determination of catalytic activity. The results demonstrated that immobilization of the CuO nanoparticle in the polymeric matrix of calcium alginate, followed by calcination at elevated temperatures, could result in notable mechanical strength and enhanced catalytic activity due to preservation of the high surface area, both valuable for practical applications. © 2011 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences.


Outokesh M.,Sharif University of Technology | Saket A.,Sharif University of Technology | Ahmadi S.J.,Jaber Ebne Hayyan Research Laboratory | Hosseinpour M.,Sharif University of Technology | Khanchi A.R.,Jaber Ebne Hayyan Research Laboratory
Industrial and Engineering Chemistry Research | Year: 2012

The current study is aimed at comparison of adsorption behaviors of silica-supported Cu nanoparticles (Si-N-Cu) and micrometric copper powder (Mi-Cu) for uptake of iodine vapor. The Si-N-Cu was synthesized by the decomposition of aqueous Cu(NO3)2 solution at supercritical condition, followed by reduction of the sample by H 2-N2 mixture. The Si-N-Cu sample with 29.4 nm Cu particles adsorbed 95% of I2 at partial pressure 10-5 bar in 1 h, while the 1 μm Mi-Cu adsorbed 51% of iodine in 6 h, indicating higher yield and faster kinetics of the nanometric sample. Theoretical analysis revealed the existence of a strong thermodynamic size effect in the Cu-I2 reaction system, so that molar |ΔG| for 2 nm Cu particles was 2.5 times larger than |ΔG| for 1 μm particles. For the Mi-Cu, kinetics obeyed a three-dimensional diffusion model, while in the case of Si-N-Cu, diffusion did not play any role in the kinetics. Apparently, no passivation mechanism was operative in the iodination. © 2012 American Chemical Society.

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