Faster plasticizers production by microwave irradiation

[EN] In this work the microwave effect of enhancing chemical reactions was applied to maleic anhydride esterification with 2-ethylhexanol-1 catalyzed by p-toluene sulfonic acid. The analysis of this reaction was simplified considering the industrial practice of withdrawn the reaction water, which makes the whole reaction act as a pseudo irreversible one. A statistical design of experiments was applied to determine an empirical chemical kinetics equation with three levels of catalyst concentration and two levels related to the kind of heating (microwave and conventional); six chemical kinetics equations (three for microwave heating and three for conventional heating) were determined. A batch/plug flow simulation was done and a spreadsheet developed for the reactor’s behavior. The most interesting result was the confirmation of a synergic effect between microwaves and acid catalysis that accelerated this esterification reaction, transforming it in a fast reaction.The authors would like to thank C. Tognela. Support from Instituto Mauá de Tecnologia – IMT – and from Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP – (Grant 2017/24238-7) are gratefully acknowledged.Jermolovicius, L.; Pouzada, E.; Castro, E.; Nascimento, R.; Senise, J. (2019). Faster plasticizers production by microwave irradiation. En AMPERE 2019. 17th International Conference on Microwave and High Frequency Heating. Editorial Universitat Politècnica de València. 379-387. https://doi.org/10.4995/AMPERE2019.2019.9777OCS37938

EXPERIMENTAL METHODOLOGY FOR GAS-LIQUID SYSTEMS

Although the gas-liquid reactions are employed in many industrial processes, this issue in the most of time is not included in the curriculum of Chemistry and Chemical Engineering courses. This work aims to propose the study of gas-liquid reaction for the degree course, considering a widespread system, the reaction of CO2-NaOH. A reaction mechanism was proposed considering all the intermediate reactions. For each point collected in the outlet solution all the products formed were quantified included residual absorbing solutions. The pH of the outlet solution received a special attention, because with this information was possible to study the controversy that there is in the state of art between some authors in consider the product of the reaction bicarbonate when under conditions of high temperature of or long exposure time of the liquid to gas. For this study was used a continuous stirred-tank reactor in which the gas phase simulate a bubble with a defined size in contact with the liquid phase. The experimental were made by trails under atmospheric pressure, using a feed mixture containing 76% to 69% of CO2 and 24% to 31% of synthetic air and as liquid solution sodium hydroxide 0.015 mol L-1, 0.08 mol L-1, 0.56 mol L-1 and 2.0 mol L-1. The experimental results obtained and the behavior of CO2-NaOH reaction were compared with the data reported in the literature and show a good performance

Carbothermal Reduction of Iron Ore Applying Microwave Energy

This paper presents the results of a study on carbothermal reduction of iron ore made under the microwave field in equipment specially developed for this purpose. The equipment allows the control of radiated and reflected microwave power, and therefore measures the microwave energy actually applied to the load in the reduction process. It also allows performing energy balances and determining the reaction rate with high levels of confidence by simultaneously measuring temperature and mass of the material upon reduction with high reproducibility. We used a microwave generator of 2.45?GHz with variable power up to 3000?W. Self-reducing pellets under argon atmosphere, containing iron ore and petroleum coke, with 3.5?g of mass and 15?mm of diameter were declined. We obtained the kinetic curves of reduction of iron ore and of energy consumption to the process in the maximum electric field, in the maximum magnetic field and at different values of power/mass. The data allow analyzing how the microwave energy was actually consumed in the reduction of ore.Maua Institute University Center of TechnologyMaua Institute University Center of TechnologyFAPESPFAPESP [02404-0]University of Sao PauloUniversity of Sao Paul

Prcess and furnace for pig iron production with microwaves

Apresentam-se o processo e o protótipo de forno para a produção de ferro gura por redução carbotérmic estimulada por micro-ondas de minério de ferro, na forma de pelotas auto-redutoras. O forno de redução com potência regulável de até 15KW de micro-ondas de 2,45 GHz foi especialmente projetado e construido para este processo. A estrutura do forno é em aço inoxidável e utiliza três geradores de micro-ondas focados para o centro de um aplicador cilíndrico.FAPESPVALECentro Universitário Instituto Mauá de Tecnologi