Journal of Applied Chemical Research
Volume:9 Issue: 3, Summer 2015

In this study, the Fenton process was used to investigate the color removal efficiency of Acid Red 52 and Basic Red 18 dye solutions by direct chemical oxidation. Color and chemical oxygen demand (COD) was successfully removed more than 99% and up to 92% respectively. This article would provide an easy assessment of the viability of using Fenton reagent in acidic conditions, so it is a promising and easy method for the fairly degradation of the BR.18 and AR.52 dye in synthetic wastewater. Parameters such as dose of H2O2:1.5g/L, concentration of Fe2: 8 mg/L as a catalyst, initial pH:3, initial dye concentration (10-500mg/L) and reaction time (18min) have been studied. The proposed system was a viable alternative to some of the more conventional forms of chemical treatment of dye solutions. Using UV-VIS spectra and COD analysis showed a good mineralization and fairly complete degradation of dye.

Density functional theory calculations were applied to investigate 13C Chemical Shielding (CS) tensors in cryptolepine (1) and its sulfur (2) and oxygen (3) isosteres. The results showed that the CS of carbon nuclei in these compounds may be divided into three types. First, carbons type α, are those directly bonded to X (X= NH, S, O) and σ33 shielding component of these carbons are deshielded in O isostere compared to N and S isosteres. The second group of carbons (β carbons) is attached to α-carbons, in which σ11 components of S isostere differs from O and N isosteres. The third carbon group, γ-carbons are positioned at a distance of three interatomic bonds or greater away from X. The replacement of N by O or S in cryptolepine isosteres has negligible influence on all components of the later carbon type. The variations of CS components could be related to the inactivity of O isostere and broad spectrum activity of S isostere.

Because of the significant role in biological processes in living cells and the diverse types of physiological activities, heterocyclic compounds are in focus of intense investigations by academic, industry and applied-oriented chemists. Considerably, ascientific renaissance of heterocycles during the last decades is closely related to the development of multicomponent approaches to their synthesis. Multicomponent methodology is fundamentally different from two-component or sequential processestogether with other innovative synthetic methods like microwave- and ultrasonic assisted reactions offer some new possibilities in constructing heterocyclic systems with high level of molecular diversity and complexity. Among them Imidazoles are quite important reagents in modern heterocyclic chemistry, and their reactions with electrophiles are the most widespread and facile synthetic approach for obtaining diverse heterocyclic systems containing Imidazolemoiety. An interest on these heterocycles is attributed to their known biological activities: analgesics, cardiovascular vasodilators, calcium channel blocking agents, potassium channel inhibitors, apoptosis-inducers, and so on. In this research, N-methyl imidazole reacts smoothly with dialkylacetylenedicarboxylates in the presence of phenylsulfonyl acetone to produce pyrroloimidazole derivatives in good yields.

Metal organic frameworks (MOFs) are considered an interesting option for hydrogen storage. These materials show an exceptional H2 uptake. Here, Zn3(BTC)2 as MOF was synthesized with a solvothermal method. The phase stability and microstructure of the Zn3(BTC)2 was characterized in terms of their properties and structures, using a number of analytical techniques including FT-IR, XRD, SEM, BET and TGA. The analyses confirmed that the product has a conical shape structure with a Langmuir specific surface area of over 25 m /g. This MOF has shown to have a hydrogen storage capacity of 0.8 wt% at room temperature and 13 bar.

A series of new polyamides containing maleimide pendant group were prepared by low temperature polycondensation of 5-(4-(2,5-dioxo-2H-pyrrol-1(5H)-yl)benzamido isophthaloyl chloride as a new monomer with various aromatic diamines in NMP. Monomer and polymers structures were identified through FT-IR, 1H-NMR and elemental analysis. Obtained polymers were soluble in polar solvents and non soluble in aprotic solvents. The inherent viscosities of the polymers have been determined in NMP and had values from 0.35 to 0.39 dL/g. Thermal stability of polymers was investigated with thermal gravimetry analysis (TGA) and diffraction scanning calorimetry (DSC). Also thermal behavior of monomer was studied with DSC analysis. X-ray diffraction measurement was used to indicate amorphous structure of polyamide.

A simple and efficient protocol for the synthesis of N-substituted pyrroles from one-pot condensation reaction of 2, 5-dimethoxytetrahydrofuran with aryl/alkyl, sulfonyl and acyl amines in the presence of ZrOCl2•8H2O in water has been developed. This new method has the advantages of simple experimental and work-up procedure, high to excellent yields, easy availability, economical, eco-friendly of the catalyst and high catalytic activity.

The present research involves effectual parameters on Cefixime trihydrate removal from aqueous solutions. Antibiotics are the main contributions in pharmaceutical waste; their presence causes major concern. The extensive utilization of antibiotics in aquaculture and prescriptions has led to the cultivation of various antibiotic-resistant bacteria and genes in wastewater. The UV-LED/ S2O8 2- process, one of the most widely (AOPs), is an effective method for industrial wastewater treatment. Sixteen experiments were required to study the effect of parameters on UV LED/ S2O8 2- removal of the drug. Each experiment was repeated three times )n=48) to calculate the mean of average. Outcomes revealed that among different parameters, peroxydisulfate concentration was the most efficient one. Based on the mean of average, optimized condition for drug removal was temperature of 50◦C, current intensity of 1800 mA, drug concentration of 10 ppm, peroxydisulfate concentration of 120 mM and 30 min for time. Consequently, 91.79 percent of drug degradation was achieved via optimum conditions.

Mesoporous carbon (CMK-3) modified with Fe3O4 nanoparticles has been successfully synthesized and characterized by powder X-ray diffraction (XRD), N2 adsorption desorption, scanning electron microscope (SEM) and transmission electron microscopy (TEM).The results depict that the synthesized Fe-CMK-3 preserved the ordered mesoporous structure of CMK-3, and magnetic species were dispersed inside channels of CMK-3 as nanoparticles with the diameter of around 15 nm. When used as adsorbents, Fe-CMK-3 and CMK-3 exhibit excellent performance for removing Malachite Green dye from aqueous solutions. Effects of contact time, pH, initial dye and salt concentrations on dye removal efficiency were investigated. Due to the facility of the separation process with an external magnetic field, Fe- CMK-3 is suggested as a novel adsorbent for the removal of MG dye from aqueous solutions.

The main objective of this search was to prepare novel soluble polyureas with improved thermal stability. Accordingly, a new types of polyureas was prepared through the polycondensation reaction of a prepared diamine containing ether, keto, and naphthyl groups with 4,4’-diphenylmethan diisocyanate (MDI), toluene-2,4-diisocyanate (TDI), and isophorone diisocyanate (IPDI) in N-methyl-2-pyrrolidone (NMP). Conventional spectroscopic methods and elemental analysis were used to characterize the structure of the monomer and polymers. The results showed that polyurea samples with the expected structure were synthesized. The inherent viscosity of polymers at a concentration of 0.5 g/dL in NMP at 30 °C was in the range of 0.55-0.60 dL/g. Thermal properties of resultant polyureas were investigated by differential scanning calorimetry and thermogravimetric analysis, and they indicated improved thermal stabilities in comparison with common polyureas. Physical properties of the polymers were also studied; they were soluble in common dipolar aprotic solvents. MDI-based polyurea showed highest thermal stability and lowest solubility among the prepared polymers.

An efficient synthesis of isoquinoline-2,3-dicarboxylates is described via one-pot reactions of isoquinoline and alkyl bromids with dialkyl acetylenedicarboxylates in water at 70 oC. The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of these methods.

In this paper, an efficient method for synthesis of aromatic polyesters containing schiff base units is described by preparation of two polyesters. These polyesters have been prepared by the reaction of terephthaloyl dichloride on Schiff bases derived from p hydroxybenzyldehyde and 4,4-diamino diphenyl ether, 4,4-diamino diphenyl methane. The Polymers were characterized by IR, CHNS, thermal analyses (TGA) and viscosities. Inherent viscosities of polyesters were in the range of 0.28-0.31 dLg-1 and thermal stability determined by TGA in nitrogen atmosphere.

Cloisite Na was used as a solid surfactant (stabilizer) in Pickering emulsion polymerization of styrene-co-butyl acrylate in presence of oil soluble initiator, azobisisobutyronitrile (AIBN) and water soluble initiator, potassium persulfate (KPS). Fourier transform infrared (FTIR) spectrum approved the corporation of Cloisite Na layers within the polymer matrix. Effect of clay content was assessed on the particle size and polymerization rate for both kinds of initiators. Reduction of particle size (nearly 100 nm) and enhancement of polymerization rate (30% and 10% for formulation with KPS and AIBN respectively) was observed by adding clay material to the blank recipe. Morphology of the particles was investigated by SEM and TEM. Formation of armored latex particles (covered particles with clay layers) with approximately 200 nm in diameter was proved via these micrographs. Furthermore, exfoliated structure of nanocomposites was revealed by XRD for sample containing water soluble initiator (ionic initiator) and oil soluble initiator. Impress of Cloisite Na structure on Tg of synthesized copolymer (soap free systems) was investigated by DSC as large changes was observed (approximately 10-15 °C). Effect of Tg on film formation of latexes was also evaluated.