Application of nanoparticles in aqueous base-fluids for intensification of absorption rate is an efficient method for absorption progress within the system incorporating bubble-liquid process. In this research, SO 2 and CO 2 were separately injected as single raising bubbles containing nanofluids to study the impact of nanoparticle effects on acidic gases absorption. In order to do this, comprehensive experimental studies were done. These works also tried to investigate the effect of different nanofluids such as water/Al 2 O 3 or water/Fe 2 O 3 or water/SiO 2 on the absorption rate. The results showed that the absorption of CO 2 and SO 2 in nanofluids significantly increases up to 77 percent in comparison with base fluid. It was also observed that the type of gas molecules and nanoparticles determine the mechanism of mass transfer enhancement by nanofluids. Additionally, our findings indicated that the values of mass transfer coefficient of SO 2 in water/Al 2 O 3 , water/Fe 2 O 3 and water/SiO 2 nanofluids are, respectively, 50%, 42% and 71% more than those of SO 2 in pure water (k LSO 2 −water = 1.45 × 10 −4 m/s). Moreover, the values for CO 2 in above nanofluids were, respectively, 117%, 103% and 88% more than those of CO 2 in water alone (k LCO 2 −water = 1.03 × 10 −4 m/s). Finally, this study tries to offer a new comprehensive correlation for mass transfer coefficient and absorption rate prediction.Processes 2019, 7, 393 2 of 21 of nanoparticles, leading to induce the micro-convections in nanofluids, has the most impact on mass transfer rate [14]. Ashrafmansouri et al. comprehensively studied previous research and reported an review to highlight the impacts of nanomaterials in heat and mass transfer processes [11]. They reported that much higher thorough studies are needed to disclose the impacts of main parameters including nanoparticles mean size and morphology on absorption rate by using nanofluids. They also exhibited that nanofluid reusing as well as absorption process modeling are the most important subjects for advancement of this technique. In addition, Kim et al. showed that mass transfer rate of ammonia is enhanced when a few nanoparticles are added to the basefluid. They exhibited that bubbles breaking by nanoparticles considerably enhances mass transfer through increasing interfacial area. They also reported that smaller bubbles were produced in nanofluid than in a base fluid, leading to intensification in mass transfer surface area [15].Ma et al. declared that by adding CNTs to a basefluid, the localized micro-convection occurs due to the Brownian motion of nanotubes [16]. They reported that induced convection can intensify the ammonia molecular diffusion within the nanofluid. Moreover, they concluded that the grazing effect can be considered another mechanism enhancing the efficiency of NH 3 by means of the bubble absorption process [16]. Absorption of gas molecules by means of the nanoparticle surfaces at the bubble interface and then removing the adsorbed gas components from the nanoparticles ...

A neuro-based computing technique is used for simulation of olefin plants at industrial scale. Artificial neural networks are applied to estimate the flow rate of the main products of the olefin unit from available information in terms of flow rate of feed streams and operating condition of furnaces. The structure of the smart model is determined through a trial-and-error procedure taking the real plant information over four successive years. The proposed paradigm estimates the tonnage of the product streams by an absolute average relative deviation in the range of 0.9 % for methane to 3.14 % for propylene. Results confirmed that this smart simulation not only presents accurate predictions, but is easy to use, straightforward, and can be simply employed for optimization and control of the unit.

The process of hydrocarbons cracking is carried out in the presence of heatresistant alloys Fe-Ni-Cr, which HP40 alloy (25Cr-35Ni) has the most applications among olefin plants. Since these alloys naturally tend to form coke, the industry has always tried to reduce the coke formation by reducing the catalytic properties of the coils. In this research, the effect of dimethyl disulphide (DMDS) concentration (200-900 ppm) on the HP40 alloy of industrial coils at the presulphidation stage is evaluated. In the presulphidation stage, the alloy surface is in contact with sulphur in the absence of hydrocarbons, and this affects the amount of coke formation in the cracking process. Also, the surface composition and morphology of coke are identified using EDX and SEM analysis. These results showed that at the 500 ppm concentration of DMDS, coke deposition is minimized. Additionally, our findings indicated that coke morphology has not changed under different presulphidation conditions, and coke is still a filament type, but the size of the filaments has changed. Moreover, the study of HP40 composition in both preoxidized and presulphide stages shows that presulphidation reduces the amount of Fe and Ni in the coke layer significantly.

Immobilized titanium tetrachloride containing was demonstrated to be an effective and water-tolerant solid acid cationic initiator for the cationic polymerization of an industrial liquid pyrolysis gasoline feedstock.

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