Kinetic Evaluation of Deactivation Pathways in Methanol-to-Hydrocarbon Catalysis on HZSM-5 with Formaldehyde, Olefinic, Dieneic, and Aromatic Co-Feeds

ACS Catalysis ◽  
2021 ◽  
pp. 3628-3637
Author(s):  
Brandon L. Foley ◽  
Blake A. Johnson ◽  
Aditya Bhan
2012 ◽  
Vol 11 (4) ◽  
pp. 829-839 ◽  
Author(s):  
Siti Rozaimah Sheikh Abdullah ◽  
Mohd Hafizuddin Muhamad ◽  
Abu Bakar Mohamad ◽  
Rakmi Abdul Rahman ◽  
Abdul Amir Hasan Kadhum

1988 ◽  
Vol 20 (11-12) ◽  
pp. 131-136 ◽  
Author(s):  
A. D. Wong ◽  
C. D. Goldsmith

The effect of discharging specific oil degrading bacteria from a chemostat to a refinery activated sludge process was determined biokinetically. Plant data for the kinetic evaluation of the waste treatment plant was collected before and during treatment. During treatment, the 500 gallon chemostatic growth chamber was operated on an eight hour hydraulic retention time, at a neutral pH, and was fed a mixture of refinery wastewater and simple sugars. The biokinetic constants k (days−1), Ks (mg/L), and K (L/mg-day) were determined before and after treatment by Monod and Lineweaver-Burk plots. Solids discharged and effluent organic concentrations were also evaluated against the mean cell retention time (MCRT). The maximum utilization rate, k, was found to increase from 0.47 to 0.95 days−1 during the operation of the chemostat. Subsequently, Ks increased from 141 to 556 mg/L. Effluent solids were shown to increase slightly with treatment. However, this was acceptable due to the polishing pond and the benefit of increased ability to accept shock loads of oily wastewater. The reason for the increased suspended solids in the effluent was most likely due to the continual addition of bacteria in exponential growth that were capable of responding to excess substrate. The effect of the chemostatic addition of specific microbial inocula to the refinery waste treatment plant has been to improve the overall organic removal capacity along with subsequent gains in plant stability.


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 635
Author(s):  
Mohamadreza Shakiba ◽  
Arash Kakoei ◽  
Iman Jafari ◽  
Erfan Rezvani Ghomi ◽  
Mohammadreza Kalaee ◽  
...  

Kinetic modeling and degradation study of liquid polysulfide (LPS)/clay nanocomposite is possible through Ozawa–Flynn–Wall (OFW) and Kissinger methods. Comparing the results of these models with experimental data leads to provide an accurate degradation kinetic evaluation of these materials. To this aim, the morphology and distribution of clay nanoparticles (CNPs) within the LPS matrix were investigated using Field Emission Scanning Electron Microscopy (FESEM) and X-ray diffraction (XRD). To evaluate the interaction between the LPS and the CNPs, the Fourier transform infrared (FTIR) identification was utilized. Furthermore, to investigate the kinetics of degradation, the thermal gravimetric analysis (TGA) and derivative thermogravimetry (DTG) of the samples were used in the nitrogen atmosphere with the help of Kissinger and Ozawa–Flynn–Wall (OFW) models. The characterization results confirmed the homogenous dispersion of the CNPs into the LPS matrix. In addition, the presence of CNPs increased the thermal stability and activation energy (Ea) of the samples at different conversion rates. Moreover, the OFW method was highly consistent with the experimental data and provided an appropriate fit for the degradation kinetics.


2018 ◽  
Vol 42 (10) ◽  
Author(s):  
Ricardo Scherer Pohndorf ◽  
Volnei Luiz Meneghetti ◽  
Flávia Fernandes Paiva ◽  
Maurício Oliveira ◽  
Moacir Cardoso Elias

2015 ◽  
Vol 24 (11) ◽  
pp. 1809-1816 ◽  
Author(s):  
Juan C. Villa-Camacho ◽  
Stephen Okajima ◽  
Miguel E. Perez-Viloria ◽  
Kempland C. Walley ◽  
David Zurakowski ◽  
...  

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