Journal of Applied Research in Chemistry
Year:2014 | Volume:8 | Issue:1|Papers Count:9

Separation of carbon monoxide, hydrogen and methane from gas mixtures is an important industrial process. In this work, the adsorption capacity of carbon molecular sieve (CMS) for these gases was studied by volumetric method at temperature of 20oC and pressure in the range of 200- 3500 kPa. Maximum adsorption of carbon monoxide, hydrogen and methane was 6.98, 3.39 and 2.77 mmol.g-1, respectively. Adsorption isotherms of these gases by using Excel showed to be a Langmuir type adsorption. Gas adsorption rate was calculated and showed that carbon monoxide, hydrogen and methane adsorptions by CMS were based on the difference between their adsorption rates and followed a kinetic rate of pseudo second-order. The maximum volume of adsorption gas of micro pores and potential energy as the parameter for predicting the type of adsorption were calculated using Dubinin-Radushkevich (DR) method. Adsorption potential energy for carbon monoxide, hydrogen and methane were in the order of 7.95, 7.78 and 7.79 kJ.mol-1.

Atom transfer radical polymerization (ATRP) provides a robust route to synthesize well-defined polymers with predetermined molecular weight and low polydispersity index. ATRP as a popular member of controlled radical polymerization (CRP) family provides some advantages over others among which the usage of different initiation techniques are unique features of ATRP. Although Reverse ATRP (RATRP) is an appropriate technique for overcoming oxidation problem, synthesis of block copolymer is impossible by this procedure. Despite RATRP, simultaneous reverse and normal initiation techniques (SR&NI) can be used to synthesize various block copolymers. Activators generated by electron transfer (AGET) and activators regenerated by electron transfer (ARGET) employ environmentally friendly reducing agents to activate a metal complex in its higher oxidation state. However, initiators for continuous activator regeneration (ICAR) initiation techniques use conventional radical initiator. Moreover, ARGET and ICAR ATRP are designed to decrease the metal catalyst concentration to ppm level, which is an important goal to industrial applications.

As carbon black is the major component in the tire formulation, recycling and reuse of it for the preparation of the new tires is very important. The basic properties of PCB were characterized. The results show that these properties are within acceptable limits for carbon black that is used in the tire industry. The effects of PCB on the processing properties of rubber compounds based on NR and the mechanical properties of vulcanizates were investigated and compared with other traditional fillers. The effect of PCB on the processing properties of compounds was similar to that of other fillers. This project gives a unique eco-friendly solution to manage waste rubbers which currently create environmental problems.

Water-soluble polyaniline is synthesized by polyaniline sulfonating with different counter ions. In this article, Emeraldine salt with Cl- counter ion is changed to water-soluble polymer by using chlorosulfonic acid. In this paper the synthesis of these polymers and their detection will be discussed. Also, surface activity of these polymers will be evaluated. Finally, the conductivity of this polymer will be discussed by using diffuse reflectance spectroscopy (DRS) technique.

The structure and size determination of synthesized magnetic nanoparticles and morphology investigation of nanocomposites containing magnetic nanoparticles have attracted a lot of interest. One of the best ways for characterization of these particles is using a magnetic force microscope equipped with a magnetic probe. In this research, a simple and reproducible technique for manufacturing magnetic force microscope probes with the aid of multiwall carbon nanotube using dielectrophoresis method has been developed. Suspensions of certain concentrations of carbon nanotubes in Ethanol–Deionized water solution and the surfactant sodium dodecyl sulfate have been prepared using an ultrasonic. In order to attach carbon nanotube to the silicon-made atomic force microscope tip, the effects of several factors such as voltage, frequency, the angle between tip and electrode, and finally the tip geometry should be investigated. To facilitate injection of CNT solution into the space between gold-coated silicon probe apex and electrode plate, the distance between them was adjusted to 30 micrometers.Experiments for investigation of voltage effect revealed that the optimum voltage to attaching CNT to the tip apex is 13 volts. Magnetic probes were covered with cobalt and then magnetic samples were imaged using these probes. The results were compared with images obtained from commercial probes and it was found that higher resolution images can be obtained with constructed probes. The fabricated tips have greater longevity that can be attributed to the elasticity and higher mechanical and thermal stability of carbon nanotubes.

Superabsorbent nanocomposite was synthesized via copolymerization of acrylic acid (AA) and polyethylene glycol (PEG) onto carrageenan. The copolymerization reaction was carried out in aqueous medium and in the presence of ammonium persulfate (APS) as initiator, N, N`-methylene bisacrylamid (MBA) as cross linker and montmorillonite (MMT) as nanoclay. The superabsorbent nanocomposite structure was confirmed by FT-IR spectroscopy and X-ray diffraction. The swelling behavior of superabsorbent nanocomposite was also investigated in distilled water and various salt solutions. Thermal properties of synthesized superabsorbent nanocomposite were studied by using thermal gravimetric analysis, differential thermal gravimeter and differential scanning calorimeter. It was observed that the high thermal resistance of nanocomposite hydrogel and hydrogel carrageenan is high.

A new fluorogenic method for the selective and sensitive determination of nickel using 2-(1-H-benzo[d]imidazol-2yl)-N-phenylhydrazincarbothioamide(L) was developed. The fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to nickel ions in CH3CN/H2O (70:30, v/v) solution. The fluorescence enhancement of L is attributed to the 1:1 complex formation between L and Ni2+, which has been utilized as the basis for selective detection of Ni2+. Under the optimum condition described, the fluorescence enhancement at 352 nm is linearly related to the concentration of nickel in the range of 1.2´10-5 to 1.6´10-7 M and a detection limit of 7.9´10-8 M. The fluorescent probe exhibits high selectivity for Ni2+ ion over the other common mono, di-and trivalent cations.

In this work, Iron-oxide nanoparticles of 13.36±3.7 nm were synthetized using co-precipitation method and the effect of their presence in Saccharopolyspora erythraea culture on the titer of erythromycin was investigated. During the fermentation, the pH, biomass and erythromycin level were measured and compared with those in the control media. Our results indicated that supplementation of the fermentation media with different concentration of Iron-oxide nanoparticles could increase the titer of erythromycin produced. The level of antibiotic production in a medium containing 0.02 w/v nanoparticles was 2.25 times higher than that in the control medium. The straightforward and inexpensive production of Iron-oxide nanoparticles, along with their positive impact on erythromycin titer promises the economically viable use of these substances to enhance the industrial production of antibiotics.