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Abstract  

A thermogravimetric method is proposed for study of the kinetic parameters of coked HZSM-5 zeolite regeneration. The technique, which makes use of integral thermogravimetric curves, was optimized by microprocessed integrated mathematical methods. The kinetic parameters obtained from the TG curves are the activation energy, the rate constants, the half-life times, and in particular the coke removal time as a function of temperature. The activation energy calculated by using the Flynn and Wall kinetic method was 81.4 kJ mol−1. It was observed that, to remove 99% of the coke from the zeolite in a period of 1 h, it would be necessary to carry out thermo-oxidation at 748 K, with a dry air purge flow of 120 cm3 min−1.

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the conversion ratio of the methyl orange. The nano-MoS 2 /AlOOH catalysts regenerated via filtration held high catalytic activities after two repeated uses. The activity of the three-time regenerated catalyst was decreased to about 73%. These

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Journal of Thermal Analysis and Calorimetry
Authors: Ana C. R. Melo, Edjane F. B. Silva, Larissa C. L. F. Araujo, Mirna F. Farias, and Antonio S. Araujo

gasoline and gas–oil. Their success is based on the ability to prepare zeolitic materials with strong Brönsted acidity that can be controlled within a certain range and which resist high reaction temperatures and catalyst regeneration conditions. The shape

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, difficulty of regeneration of solid heteropoly acid catalysts (decoking) [ 34 ]. The temperature at which H 3 PW 12 O 40 starts loss of all acidic protons is 465 °C and complete decomposition to the constituent oxides occurs at 610 °C. Catalyst regeneration

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SAPO-34 catalyst, regeneration should be performed simultaneously while obvious deactivation is observed. Hence, at least one more plant with identical construction is needed in parallel for the switch of reaction and regeneration mode. The optimization

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.949 The H 2 O 2 /Fe 2+ system involves several cyclical reactions with catalyst regeneration, as shown in Eqs. 2 – 9 . In H 2 O 2 /Fe 3+ , the reaction sequence begins with Eq. 3 [ 2 , 15 , 25 , 37 , 39 ]. The reaction mechanisms of Na 2 S 2 O 8

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the ratio between the quantity of 4-PBP formed and the total quantity of products yielded at each time. Catalyst regeneration In order to examine the regenerability of the catalysts, three reaction cycles (fresh and

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hydrogen between two experimental points) for catalyst regeneration. Researchers using the same catalyst are of divided opinion. Lin et al. [ 11 , 14 ] and Rousse et al. [ 6 ] observed deactivation while Castano et al. [ 20 ] reported no deactivation. This

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