Journal of Applied Research in Chemistry
Year:2013 | Volume:6 | Issue:4|Papers Count:8

In this study synthesis of activated carbon from pistachio shell as precursor by physical activation in rotary reactor using carbon dioxide and steam as oxidizing agents was investigated. The optimum conditions were obtained. The effects of activation temperature, dwell time, and gas flow rate on iodine number and Burn off were investigated in optimum conditions. After analysis and optimization, the activated carbon with the iodine number of 1452.14 mg/g and the Burn off of 43.86 at 866.5oC, 26.2 min and 38 lit/min was produced. At 816.5oC, 40 min, and 47.4 lit/min an activated carbon with the iodine number of 1464.52 mg/g and the Burn off of 21.83 was obtained. Finally, the experiments were carried out in optimal conditions. There was good agreement between experimental results and the predicted values obtained from the software. The optimum iodine number and burn off showed that steam as an activation agent was more appropriate than carbon dioxide.

In this study, after preparation and characterization of graphene oxide sheets, immoblization of Fe (OH)3 nano particles was carried out by a chemical deposition method. Graphene oxide and its composite were characterized by FT-IR, XRD, Raman, AFM, and SEM. It was shown that the iron (III) hydroxide particles were 24.45 nm and homogeneously deposited on the surfaces of the graphene oxide sheets. The adsorption percentage of Cr3+, Co2+, Ni2+, Zn2+ and Pb2+ metal ions in presence of this composite were 29.30, 3.85, 35.00, 7.85 and 98.83, respectively. The experimental data demonstrate selective adsorption of Pb (II) ion on the composite.

Isocyanate containing prepolymers were prepared from the toluene diisocyanate and glycidal azido polymer diol. The NCO number of the resulting prepolymer was determined by derivatization of isocyanate functional group using hexafluoro isopropyl alcohol and recording 19FNMR spectrum. Quantitative analysis was carried out by the integration of 19F signals of the resulting derivatives and internal standard. Accuracy of this method was verified using a known diisocyanates, such as pure toluene diisocyanate and MDI. A good correlation was found between the results obtained by the current 19FNMR method and titration method. 19FNMR method has advantages, such as high sensitivity and convenient procedure within a short period, over the titration method.

In this paper, solid phase transformation of titanium oxide nanoparticles at different heat treatment conditions were investigated using different developed kinetic models. The agreement of the developed models which are a combination of nucleation and growth, with experimental data for solid phase transformation of titania with nanoparticle size at dry heat treatment and hydrothermal conditions were checked and the results show that the developed models are able to predict kinetic transformation of titanium oxide polymorph. Result also shows that nucleation mechanism of Anatase formation from amorphous solid phase in a solution is a surface nucleation and at dry heat treatments at temperatures of 300-400oC is of combined interface and surface nucleation. Researchers have stated that in solid transformation of Anatase nanocrystals to Rutile at temperature below 600oC, transformation occurs by interface nucleation mechanism. The results of this work show that due to particle growth at dry heat treatment condition at long period of time, surface nucleation can also play an important role. The advantage of the models developed in this work over other models is that, these models can predict the solid phase transformation of TiO2 nanoparticles without the need for data on titanium oxide nanoparticle size.

This contribution proposes the modeling and validating results of a CO2 packed bed absorber operating with 2-Amino 2-Methyl Propanol (AMP). The rate-base model presented in this work considers mass transfer, heat of absorption and evaporation, solubility of CO2 inside the amin solution, absortion reaction, enhancement facror, thermodynamic equilibrium, and mass diffusion resistances in gas and liquid interface. All differential and algebric equations of the mathematical model are implemented in the MATLAB program, and they are solved numerically as a boundary value problem using the corresponding MATLAB function. Then, the proposed model is validated against both the experimental and modeling results gathered from the literature. The results obtained by the presented model in this research are in good agreement with the pilot plant data, and it can predict the mole fraction of CO2 in gas phase, liquid temperature and CO2 loading with the AAD% of 8.46, 2.47 and 12.33, respectively. Moreover, in comparison with the results of the other proposed model in the literature, the AAD% of the predicted CO2 mole fraction in the gas phase and temperatue of the liquid decrease to the extent of 13.094% and 5.56%, respectively.

In this paper, quantitative structure–activity relationship (QSAR) of 38 amini acid derivatives as potent inhibitor of histone deacetylase (HDAC) enzyme for the treatment of cancer and other diseases was studied. These enzymes catalyze the removal of acetyl groups from the lysine residues of proteins including histones.A suitable set of molecular descriptors was calculated and the step-wise was employed to select four descriptors that resulted in the best fitted models. Multiple linear regression (MLR) and artificial neural network (ANN) were performed to build the models. Comparison the results of these two methods reveals that those obtained by the ANN model have much more prediction capability.

As the changes of formulation of rubber compounds will affected their properties and FTIR spectra, finding the correlation between rheological properties and spectral behavior of blends would be so important. In this work, according to the data obtained by FTIR spectra of rubber compounds, at last 2models were demonstrated for predicting the properties of blends, which were correlated with rheological properties.

In this research, titania nanoparticles were encapsulated into the prepared zeolite NiX, CoX and ZnX using ammonium titanyl oxalate monohydrate as a source of titanium. The zeolite MX (M=Ni, Co, Zn) was obtained via mixing of as prepared zeolite NH4X with M (NO3)2 solution. The synthesized samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis diffuse reflectance spectroscopy (DRS), and energy dispersive X-ray spectroscopy (EDX). Morphology of the samples was studied by scanning electron microscope (SEM). The results indicate that the crystallization percentages of these samples are relatively high compare to zeolite NaX; and Ni, Co, Zn and Ti can be replaced in zeolite X in the octahedral and tetrahedral positions. The photocatalytic behaviors of the prepared samples were studied in decomposition of nitrophenol and phenol under UV irradiation. The obtained results showed that the photocatalytic activity of CoTiX nanoparticles was higher than the other samples and the the percentage of nitrophenol decomposition in the presence of CoTiX was more than that of phenol.