Sharif Digital Repository

The kinetic experiments for the reaction of synthesis gas to light olefin over CO/Mn/TiO 2 catalyst were carried out in a micro-fixed-bed reactor. Rate expressions for reactions were selected based on the carbide mechanism. A differential reactor model considering both FTS and WGS kinetic models was used to describe the reaction systems. The simulation estimation of proposed kinetic model was conducted with a generic algorithm. This is an abstract of a paper presented at the 8th World Congress of Chemical Engineering (Montréal, Quebec, Canada 8/23-27/2009)  

The effect of operation variables, such as the H2/CO molar feed ratio, gas hourly space velocity (GHSV), temperature, and pressure, on the catalytic performance of the Co/Mn/TiO2 catalyst prepared at the Research Institute of the Petroleum Industry (RIPI) was investigated, and optimum reactor conditions were obtained to produce the maximum amount of light olefins. The catalyst was prepared by co-precipitation of Co and Mn phases in the presence of commercial TiO2 with maximum selectivity for ethylene and propylene production. It was found that the [H2]/[CO]=2/1, space velocity (GHSV) of 1800 h-1, 280°C temperature and 4 bar pressure were optimum operating conditions for the modified catalyst... 

Lanthanum hydroxide (La(OH)3) nanostructures, including elliptical nanoparticles, octahedral rods and irregular nanoparticles were prepared chemically in NaOH and KOH solutions with 10 M concentration. The obtained powders were characterized with XRD, SEM, TEM and DTA. Crystallinities, morphologies and thermal behavior of the obtained nanostructure powders were investigated under the influence of above mentioned solvents. The effect of chemical's temperature was also determined in one of the solvents (i.e. NaOH). The formation of growth in nanostructure mechanism under the influence of alkali solutions (i.e., KOH and NaOH) have been discussed considerably in this paper  

Recently, super gas wet and gas wet surfaces have been extensively attended in petroleum industry, as supported by the increasing number of publications in the last decade related to wettability alteration in gas condensate reservoirs. In many cases, contact angle measurement has been employed to assess the wettability alteration. Even though contact angle measurement seems to be a straightforward approach, there exist many misuses of this technique and consequently misinterpretation of the corresponding results. In this regard, a critical inspection of the most recent updated concepts and the intervening parameters in the contact angle based wettability evaluation of liquid-solid-gas... 

Recently, super gas wet and gas wet surfaces have been extensively attended in petroleum industry, as supported by the increasing number of publications in the last decade related to wettability alteration in gas condensate reservoirs. In many cases, contact angle measurement has been employed to assess the wettability alteration. Even though contact angle measurement seems to be a straightforward approach, there exist many misuses of this technique and consequently misinterpretation of the corresponding results. In this regard, a critical inspection of the most recent updated concepts and the intervening parameters in the contact angle based wettability evaluation of liquid-solid-gas...