Chemical Engineering Commons^™

Surface Structure Of Alkylsilylated Hzsm-5 As Phase-Boundary Catalyst, Hadi Nur, Yun Hau Ng, Mohd Nazlan Mohd Muhid, Halimaton Hamdan

Yun Hau Ng

The need for cleaner environment concerns motivates the development of more efficient catalytic system. Based on this consideration, recently a novel catalyst named "Phase-boundary catalyst", a bimodal amphiphilic solid catalyst, was proposed. It was demonstrated that the catalytic system containing phase-boundary catalyst required neither stirring to make an emulsion nor addition of a co-solvent to make a homogeneous solution to drive the reaction. The driving force that has prompted this paper is to investigate the surface structure of alkylsilylated HZSM-5 as phase-boundary catalyst. Temperature Programmed Desorption (TPD) of ammonia and, 13C and 29Si MAS NMR spectroscopy were used to elucidate …

Screening Of Mgo- And Ceo2-Based Catalysts For Carbon Dioxide Oxidative Coupling Of Methane To C2+ Hydrocarbon, Istadi, Nor Aishah Saidina Amin

Istadi

The catalyst screening tests for carbon dioxide oxidative coupling of methane (CO2-OCM) have been investigated over ternary and binary metal oxide catalysts. The catalysts are prepared by doping MgO- and CeO2-based solids with oxides from alkali (Li2O), alkaline earth (CaO), and transition metal groups (WO3 or MnO). The presence of the peroxide (O2_2 ) active sites on the Li2O2, revealed by Raman spectroscopy, may be the key factor in the enhanced performance of some of the Li2O/MgO catalysts. The high reducibility of the CeO2 catalyst, an important factor in the CO2-OCM catalyst activity, may be enhanced by the presence of …

Effect Of Hydrotreating Fcc Feedstock On Product Distribution, Rafael Maya-Yescas

Rafael Maya-Yescas

The demand of low-sulfur fuels has been increasing during the last 20 years due to environmental concerns about SOx emissions from processing plants and engines. Due to its high contribution to the gasoline pool, hydrotreating fluid catalytic cracking (FCC) feedstock offers several advantages, such as the increase of conversion and yields of gasoline and liquid-phase gas, meanwhile sulfur content in fuels is diminished. However, there are more important factors to be considered when hydrotreating FCC feedstock. In this work, two FCC feedstocks, typical and hydrotreated, were converted in a microactivity test (MAT) reactor, as described by ASTM D-3907-92, at different …

Translation Of Mat Kinetic Data To Model Industrial Catalytic Cracking Units, Rafael Maya-Yescas, Elizabeth León-Becerril, Daniel Salazar-Sotelo

Rafael Maya-Yescas

Bench and laboratory scale reactors are required to infer kinetic data for catalytic cracking units. One of the most common methods is the microactivity test (MAT, ASTM D-3902-92), that emulates the catalyst-to-oil ratio using a fixed-bed reactor and a semi-batch accumulator of liquids. Translation of data obtained from MAT tests in order to infer kinetic parameter to model continuous industrial units is, consequently, difficult and uncertain. In this work, the extraction of kinetic data obtained in a MAT reactor is analyzed. Estimation of a kinetic rate equation to evaluate instantaneous conversion in MAT reactors is performed. The activation energy obtained …

Efficient Wastewater Treatment Process For Brine Water, Carl Vavra, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

The objective of this project is to develop a simple, economically feasible process for purifying salt water (brine) solutions. It involves choosing the best membrane for optimum performance, while reviewing durability, membrane service life, separation capabilities and costs. Scale-up data are collected to evaluate the commercial feasibility of this technology. The optimization of processing parameters (pressure, flow, temperature and concentration) is reviewed to maximize the performance of the membrane. Cleaning and sanitizing the membrane after use for storage and reuse will also need to be studied.

An Adsorbent Prepared For Fluoride Removal From Water, Rodolfo Trejo-Vázquez, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

In this paper, we report the preparation of an adsorbent for fluoride removal from drinking water. This adsorbent was prepared using a thermal treatment of pseudoboehmite agglomerates. Taguchi and Surface Response methodologies were used in order to standardize the adsorbent synthesis and to obtain the best fluoride removal rate of adsorbent. The fluoride removal rate of our adsorbent was higher than those obtained for a commercial alumina and bone charcoal. This adsorbent was also tested and compared using different experimental conditions with fluoride solutions and tap water.

Magnetophoresis Of Nonmagnetic, Submicrometer Particles In Magnetic Fluids, Seif-Eddeen K. Fateen

Seif-Eddeen K Fateen

No abstract provided.

Effective Approach To Cyclic Steady State In The Catalytic Reverse-Flow Combustion Of Methane, Krzysztof Gosiewski

Krzysztof Gosiewski

Computer-based simulations of a reverse-flow reactor should be carried out till the attainment of the so-called cyclic steady state. Usuallythis state is achieved bythe method of direct dynamic simulations. In the paper of Unger et al. (Comput. Chem. Eng. 21 (1997) 5167.) special approaches, making use of various minimization algorithms based most often on Newton algorithms, are proposed. In the present paper one deals with a comparison and an appraisal of these methods, applied to the reverse-flow catalytic combustion of methane that occurs in coal-mine ventilation air.

Air Quality Regulation Policy In Portugal, João F. Gomes

João F Gomes

Ten years after the publication of first air quality laws in Portugal, and seven years after the publication of the respective emission limits, it seems appropriate to analyse the degree of law enforcement by the Portuguese manufacturing industry. Therefore, based on the emission measurements made regularly by ISQ, as the only officially accredited laboratory, a set of about 400 sources is analysed in terms of the compliance with the emission limits regarding total suspended particulate, sulphur dioxide, nitrogen oxides and VOCs. The compliance is evaluated through a non-dimensional parameter and plotted versus the emission flow rate to derive conclusions: it …

Dynamics Of Two-Phase Reactors With Approximate Kinetics, Francisco J. Valdes-Parada

Francisco J. Valdes-Parada

Los sistemas de transporte y reacción en más de una fase han ido adquiriendo un interés creciente en la comunidad científica y tecnológica debido a que la gran mayoría de los procesos industriales se llevan a cabo en sistemas no homogéneos. De la misma forma, es notable el interés que se ha dado en las últimas décadas por los sistemas catalizados por enzimas.

Las enzimas como catalizadores son utilizadas actualmente en una gran variedad de procesos, como son la fabricación de etanol, insulina, ácido láctico, cerveza, vacunas, entre muchos otros; de hecho varias procesos clásicos han sido reemplazados por procesos …