Journal of Iranian Chemical Engineering (Farsi Edition)
Year:2013 | Volume:12 | Issue:66|Papers Count:12

In this project, extraction of Magnesium Chloride has been studied and a semi-industrial method, which uses calcimined dolomite, has been suggested. In order to determine the effect of different factors such as time, pH and etc. on the product yield artificial solution containing distinct of Mg2+ and SO42- were prepared and then the best condition of extraction of Magnesium salt was studied. The real samples were prepared from Urmia Lake, and similar studies were performed on them. Measurement of Calcium and Magnesium ions existing in extracted samples has been done Using titration method.

Growth of population and over consumption of fossil fuel has caused an increase in the degree of pollution in the last decade. Owing to the environmental awareness, it seems necessary to find a way to predict the amount of pollutants such as ozone which is toxic. Neuro-fuzzy systems are a powerful tool for modeling and simulation of such processes. In this work, we have adopted ANFIS algorithm for predicting the level of ozone concentration in the city of Mashhad. The inputs of the algorithm are the concentration of hydrocarbons (except methane), mono and dioxide of nitrogen, temperature, wind speed and direction. For the output, the concentration of ozone has been chosen. The percentage of error for this work are 1.8 and 2.4 for the training and trial data, respectively. The result of this research reveals that the error resulted from LSE are lower compared to the combined algorithm.

In recent decades, due to decreasing environmental pollution, many attempts have been carried out for developing biodegradable packaging systems and improving its efficiency. Composites containing fillers that have one dimension in a nano-size are called nanocomposites. During recent years, many efforts have been carried out to produce fully biodegradable nanocomposites by using of mixing different polysaccharide nanocrystals (from various sources as filler) with a biodegradable polymer matrix. Using of cellulose micro and nanocrystals has been considerd in the nanocomposites due to have good mechanical strength, high thermal stability and low density as fillers and reinforcement material. Replacement nanoclay with cellulose nanocrystals is leading to production of fully biodegradable nanocomposite. The producing nanocomposite with good mechanical, thermal, permeability properties and completely biodegradable structure, can be suitable progress in producing packaging system.

Treatment and fractionation of the whey have been considered by many researchers in recent years, in aspect of environmental protection because of its high pollution effects and also in aspect of reaching to the high valuable whey proteins. Among the conventional methods for the fractionation of the whey proteins, membrane technologies is more suitable, because of the high quality of achieved proteins, easy scale-up, short production time and low production cost compared to the adsorption. Membranes used for the fractionation of whey proteins are classified to two general categories include ceramic and polymeric membranes. The obtained results based on the articles presented in the literature showed that in spite of polymeric membranes have high flux, but ceramic membranes indicated high selectivity for the fractionation of desirable proteins related to the undesirable one besides having advantages such as high mechanical strength and chemical resistance.

Qualitative and quantitative measurement of food components is important because of high costs of conventional methods and also tendency to precise and sensitive detection of these compounds. From those components that their determination is very common are glucose and cholesterol. Many procedures have been used for detection and determination of these compounds, but need for accurate measurements with high sensitivity of these compounds, especially in food safety issues have been caused biological methods developments, especially biosensors. Among these, biosensors based on conducting polymers nanostructures especially polyaniline have recently got attention because of their exclusive properties. In this paper, studies on polyaniline based biosensors for glucose and cholesterol detection are reviewed.

Recently, the reduction of gaseous pollutants and greenhouse gases gets more attention by environmental scientists. The absorption of a gas into a liquid phase is one of the ways that is applied to remove a gaseous pollutant from environment. Therefore, a lot of researches have been carried out to improve the absorption performance. Nanotechnology is one of the techniques can be applied to absorption systems to enhance the mass transfer coefficient, resulting an improvement in absorption process. Recently, due to the development of nanotechnology, many researches on nanofluids have been carried out successfully as an effective way to enhance the mass transfer performance. This paper reviews the application of nanofluids for enhancing mass transfer during recent years. Although the mechanism of this enhancement is not still clear, some reasons are suggested for the mass transfer enhancement in gas-liquid systems, especially ammonia absorption systems, the micro-convection in nanofluids because of the Brownian motion of nanoparticles and the gas holdup increasing in nanofluids are the most important ones of those reasons. Also the improvement of heat transfer at the gas–liquid interface increases the absorption potential. Key parameters of the absorption process are dose and type of nanoparticles and also inlet gas flow rate which are mostly investigated in the literatures.

In the present investigation, the influences of heat exchanger replacement in Abadan Oil Refinery Company were investigated on gas consumption and performance of flash drum vessel. The results showed that gas consumption was increased by 3.3 percent and value of vapor generation by flash drum vessel 62 percent was decreased. On the other hand, the temperature of preheated crude oil as an important parameter was decreased. It decreased from 223oC to 220oC after revamping. This study shows energy consumption and environment pollutions created by these changing.

The activation and conversion of methane to higher hydrocarbons and hydrogen is a great challenge to catalysis science. In addition to oxidative activation of methane such as oxidative coupling to C2+ hydrocarbons, the non-oxidative activation of methane to aromatics has been received extensive attention since 1993. Non-oxidative conversion of methane is strongly limited by the thermodynamics of the process. However, the transition from the present era of fossil fuels to the coming hydrogen energy age makes this process an interesting and important approach in comparison with the direct oxidative conversion of methane. This paper presents a comprehensive review of the direct conversion of CH4 to aromatics under non-oxidative conditions. The catalysts, mechanisms and kinetics of the reaction, types of reactors and process conditions, along with the carbonaceous deposits formation are discussed.

The aim of this research is developing an Aluminum-Oxygen (Al-O2) fuel cell for propulsion of Autonomous Underwater Vehicles (AUV). The constructed single cell, is the first sample of Al-O2 fuel cell which is developed at Iran to now. This fuel cell has been modified, to be able used in a closed cycle for under water applications. It also simply can be scaled up. In the experiments, chemical and instrumental variables were optimized in three steps. The results showed that a single cell with effective area of 75 cm2 can produce maximum 10 watt power at voltage 0.95 volt. in the next step we designed a 500 watt stack according to the results obtained from single cell evaluations. Regards to the weight and the volume of the designed 500 watt Al-O2 fuel cell, it can be used at the AUVs.