Electrochemical behavior and the determination of furan in beverage samples using glassy carbon electrode

Furan is a possible human carcinogen in many types of foods. A new and sensitive electro analytical method for determination of furan has been developed and validated. The best condition for electrochemical response was obtained with 0.1 M britton-rabinson buffer solution [pH=5] a glassy carbon electrode [GCE] was used as the working electrode, a Ag/AgCl/ KCl[sat.] electrode served as the reference electrode, and a platinum wire as the auxiliary electrode under the Differential Pulse Voltammetry [DPV] mode. The peak current obtained from DPV was linearly dependent on the Furan concentration in the range 12-360 Micro M [0.81-24.5 ppm] with correlation coefficients of 0.999 and a limit of detection [LOD] of 3 Micro M [0.2 ppm] and limit of quantification [LOQ] of 10 Micro M [0.68 ppm] were calculated, respectively. The values of the electron-transfer coefficient [Alpha] involved in the rate determining step calculated from the linear plots of Ep against ln [v] in the pH range investigated were 0.8 confirming the irreversible nature of the oxidation peak. The reproducibility of the method was tested by analyzing 10 samples containing 30 Micro M of Furan. The RSD% of the method thus obtained was 3.0% which showed excellent reproducibility for this developed methods

Pre-concentration and determination of platinum [IV] in water samples using chelating resin by inductively coupled plasma atomic emission spectroscopy [ICP-AES]

A chelating resin is prepared by condensation polymerization of aniline with formaldehyde and characterized by FT-IR, elemental analysis and studied for the preconcentration and determination of trace Platinum ion from environmental water sample using inductively coupled plasma-atomic emission spectroscopy [ICP-AES]. The optimum pH value for sorption of the metal ions was 5. The maximum adsorption capacities of resin [aniline- formaldehyde] were determined as 21.25, 14.72 and 11.9 mg/g at different temperatures 20, 30 and 40°C, respectively. The best desorption of the metal ions from resin was obtained by 0.5 mol/L nitric acid as eluting agent. The profile of Platinum uptake on this sorbent reflects good accessibility of the chelating sites in the aniline-formaldehyde. The equilibrium adsorption data of Platinum ion modified resin were analyzed by four isotherm models such as Langmuir, Freundlich ,Temkin and Redlich-Peterson. Langmuir isotherm parameters obtained from the four Langmuir linear equations by using linear method, Langmuir-1 is the most popular linear form, and it had the highest coefficient of determination compared with the other Langmuir linear equations. The thermodynamic parameters [DELTAG, DELTAH, and DELTAS] were also determined using the equilibrium constant values obtained at different temperatures. The results showed that the adsorption for Pt [IV] ion was spontaneous nature and exothermic. The method was applied for Platinum ions determination from tap water sample

New chelating resin for preconcentration and determination of molybdenum by inductive couple plasma atomic emission spectroscopy

A chelating resin is prepared by condensation polymerization of aniline with formaldehyde and characterized by Fourier transform infrared spectrometer, elemental analysis and thermogravimetric analysis and studied for the preconcentration and determination of trace Molybdate ion from environmental water sample using inductive couple plasma atomic emission spectroscopy. The optimum pH value for sorption of the metal ion was 5. The sorption capacity of functionalized resin is 3.1 mg/g. The chelating sorbent can be reused for 20 cycles of sorption-desorption without any significant change in sorption capacity. The best desorption of the metal ions from resin was obtained by 0.5 mol/L nitric acid as eluting agent. The profile of molybdenum uptake on this sorbent reflects good accessibility of the chelating sites in the aniline- formaldehyde. Scatchard analysis revealed that the homogeneous binding sites were formed in the polymers. The equilibrium adsorption data of Molybdate ion modified resin were analyzed by five isotherm models such as Langmuir, Freundlich and Temkin. Langmuir isotherm parameters obtained from the four Langmuir linear equations by using linear method. Based on the Langmuir isotherm analysis, the monolayer adsorption capacity was determined to be 4.03 mg/g at 20 °C. The method was applied for molybdenum ions determination from river water sample

new potentionmetric sensor for determination of cesium ion in environmental samples

A new cesium ion selective PVC membrane based on parent calix [4] arene was developed for potentiometric determination of cesium in environmental samples. The electrode based on p-5, 11,17,23 tetra [tert-butyl] 25,26,27,28-tetrahydoxy calix [4] arene [TCH] as ionophor, dibutyl phthalate [DBP] as plasticizer, sodium tetra phenyl borate [NaTPB] and oleic acid as lipophilic salt and additive showed the best performance. The electrode exhibits a good Nernstian response in a concentration range of 1x10 [-1]-3.16x 10[-5] M of cesium, with a slope of 58.5 +/- 0.6 mv per decade and a detection limit of 1.58 x 10 [-5] M. It exhibits a good selectivity for cesium in comparison with alkali, alkaline earth, and dome transition metal ions. The electrode response and selectivity remained almost unchanged for more than a month. The effect of membrane composition, pH and concentration of internal solution on the potential response of the electrode were also studied. The applicability of the electrode to real samples was also assessed

Reduction of environmental pollution through optimization of energy use in cement industries

Industrial development has lead to higher energy consumption, emission of greenhouse gases, as well as air pollutants. Cement factories play an important role in over all greenhouse emissions. This study aims to investigate the role of Iranian cement industries and their contribution of greenhouse gases contribution. The measured emission factors for oil and fuel gas shows that carbon dioxide contribution from fuel oil based cement industries is almost 2.7 times higher than gas based cement factories. The strength, weakness, opportunity and threat technique analysis showed that the best strategy to combat greenhouse gases from Iranian cement factory is to implement energy efficiency measures. Further, strategic position and action evaluation matrix analysis indicates that Iranian cement industries fall within invasive category. Therefore, exploitation of opportunities must carefully be used. One of these opportunities is the utilization of financial assistance provided by clean development mechanism. The results show that replacement of ball mills with vertical roller mill can reduce the electricity consumption from 44.6 to 28 kWh/ton. As a result of such substitution about 720 million kWh/y of electricity would be saved [almost a power plant of 125 MW capacities]. Though implementation of new mills may not be economic for the cement industries' owner, but the overall gain for the government of Iran will be about US$ 304 million. If the duration of such efficiency measure is considered as about 12 y, then the overall CO2 reduction/phase-out would be around 4.3 million tons