مریم تخت روانچی

Olefin-paraffin separation with equivalent carbon number is an important cost-effective step in olefin production in petrochemical industries. Liquid membrane technology using ionic solutions can perform olefin-paraffin separation in a selective manner. In this paper, the separation of light olefin-paraffin mixtures using supported liquid membrane is modeled in an unsteady-state manner. In this model, mass transfer is considered in the direction of membrane thickness and the effect of feed pressure, silver concentration, solvent type and time on flux rate was investigated. For model evaluation, experimental data of ethylene-ethane separation with aqueous solution of silver nitrate and propylene-propane separation with aqueous solution of silver nitrate, AgNO3-NMP and AgBF4-BMImBF4 were used. There is a good agreement between experimental and modeling data (with 12.2% difference). Moreover, it was concluded that by using viscose or ionic liquids, which are substituted for water (solvent) in order to solve evaporation problems, cause a decrease in flux and product selectivity.

Regarding environmental effects of NOx emission and negative effects of nitrogen containing compounds (NCCs) on the performance of hydrogen desulfurization (HDS) process, adsorptive denitrogenization (ADN) before HDS process is very important. Metal organic frameworks (MOFs) are a new adsorbent group, which is highly studied for AND process. The goal of this paper is to compare quinolone (QUI) adsorption capacity and QUI/ dibenzothiophene (DBT) selectivity on the OPA-1 and OPA-2 adsorbents (based on the MIL-100 and MIL-101, respectively). These adsorbents were characterized by XRD, FTIR and specific surface area (BET). Isotherm and kinetic studies indicated that the Langmuir isotherm and pseudo-first-order model can successfully describe the experimental data. Among the studied adsorbents, OPA-2 with maximum adsorption capacity equal 91.49 mgN/gads and QUI/DBT selectivity equal 24.56 had the best performance for QUI selective adsorption. The adsorption capacity and selectivity for removal NCCs from industrial sample were 14.65 mgN/gads and 17.69, respectively.

In this paper, the deactivation of Pd-Ag/Al2O3 catalyst was investigated in acetylene selective hydrogenation. Therefore, the commercial catalyst performance was used in Godinez kinetic model. The deactivation kinetic constant of catalyst was calculated by appropriate deactivation order. The activity of main and side reaction was evaluated during time on stream.
If first or second deactivation kinetic order was assumed, the activity lost was 90% and 1%, respectively. Since lower order was increased deactivation, so the second order deactivation model was proposed. As well the effect of temperature on the activity lost by using this model in acetylene selective hydrogenation was investigated.

Adsorption process with activated carbon is one of the most common methods for heavy metals removal from various wastewaters. In this study, modeling of of Pb2,Cd2,Ni2 adsorption have been investigated with activated carbon in equilibrium and kinetic states. Langmuir, Freundlich, Redlich-Peterson and Sips isotherms were applied for study of equilibrium in single adsorption systems and multicomponent Langmuir isotherm was selected for equilibrium study in multicomponent adsorption system. All studied isotherms had good prediction for equilibrium of these systems. Pseudo-first order, pseudo second order and film-pore volume diffusion model were applied for investigation of adsorptionkinetics. According to the results, film-pore volume diffusion model based Langmuir isotherm had minimum average relative error. Effective pore volume diffusivity was determined 1.9210-6 cm2.s-1, 1.9010-6 cm2.s-1 and 1.2010-6 cm2.s-1, for Pb2, Cd2 and Ni2, respectively.

The role of international co operations in developing and transferring the technology of commercial catalysts production is studied in this article. The methodology used in benchmarking، preparing and gathering information along with their analysis performed by Kieza technology acquisition model. To specify the benchmarking، the criteria such as development rate، oil resources status، and geopolitics are used. Brazil، Saudi Arabia and Kuwait were the benchmarked countries which have acquired the technologies related to commercial catalyst production through international co operations in recent decades. Based on this study، the common investment is the best method to transfer catalysts technology. The concentration on growing catalysts with export expansion approach is suggested as well.

From a global point of view, petrochemical industries were always competitive. Specially, because of fluctuations in product's price and high price of feedstocks, earning money in petrochemicals is always a challenge. In the case that cheap feedstocks are not available, the best method of profitability is integrational optimization in petrochemical complexes and in their adjacent refineries. This fact is valid for installed plants and plants under construction. Petrochemcial-refinery integration is an important factor in reducing costs and increasing efficiencies. Moreover, it guarantees the supply of feedstock for petrochemical industries. Integrated schemes benefits from the economy of scale. On the other hand, an integrated complex can produce more diverse products. “Benchmarking” is the methodology used in this study. Petrochemical- refinery integration avoids selling crude oil, optimizes products, economizes costs and increases benefits. Nowadays, there is an integration approach in various commercial processes of well-known licencing companies.

Catalysts, as accelerating agents of chemical conversions, are of great importance in petroleum and petrochemical industries. The catalyst production technology is knowledge-based, highly competitive and secretive and; consequently, in the scientific literature very little information can be found in this field. Despite extensive research efforts on development of catalyst formulations in lab and pilot scales, none of the domestic formulations has been implemented at industrial level. The few practices in catalyst production technology transfer from foreign companies have been unsuccessful due to improper implementation of technology transfer and acquisition, as well as, improper selection of the technology supplier. In this work, the development of commercial catalysts from lab to industry along with the related difficulties in their commercialization is studied and guidelines for their domestic production are provided. Unsuccessful domestic and certain successful foreign experiences for domestic catalyst production, as benchmarks, are also reviewed.

Membrane separation systems as capable tools selectively separating a specific component have attracted the affeation of many researchers. This method of separation has application in different engineering aspects such as chemical engineering. In the present paper, the application of membrane systems for the separation of iodine, chromium and gold ions which have environmental importance and for the separation of carbon dioxide and olefin-paraffin mixtures that have industrial importance has been reviewed.

Paying attention to cultural and social developments besides the economical aspects, is very important. Human, plays an important role in countries development. As women have effective influence on a country’s development, their role in reaching this goal must be considered. In this paper, women’s participation in engineering fields and professions in different countries around the world, especially in Iran, are considered and compared.

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