Fifty Years of Moment Technique for Dynamic Analysis of Chemical Reactor Parameters

Doğu, Timur
Moment technique has been extensively used for the evaluation of the rate and equilibrium parameters in chemical reactors and also in adsorption vessels, for about five decades. Adsorption and reaction rate parameters, as well as axial dispersion constants, effective diffusivities within porous catalysts and heat and mass transfer coefficients were shown to be effectively evaluated by analyzing the moments of the response peaks, which could be obtained from pulse-response experiments performed in a reaction/adsorption vessel. A detailed review of chromatographic processes, involving moment analysis of adsorption equilibrium and rate constants in fixed beds, dynamic analysis of batch adsorbers, moment analysis of fluidized bed, slurry and trickle bed reactors are reported in this manuscript. Applications of the single-pellet moment technique, which was developed for the effective investigation of intrapellet rate and equilibrium processes, by eliminating the contributions of axial dispersion and external transport parameters, are comprehensively discussed. Recent studies for the analysis of reaction rate parameters using the TAP reactor approach, use of single pellet system for the investigation of catalytic and non-catalytic solid-gas reactions and extension of the moment technique to non-linear systems opened new pathways in reaction engineering research.


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Effective diffusivities and adsorption equilibrium constants of methanol, ethanol and 2-methyl-2-butene (2M2B), in Amberlyst 15, were evaluated from batch adsorption experiments. Moment expressions derived for different models involving diffusion resistances in the macropores and within the gel-like micrograins were used for the evaluation of effective diffusion coefficients. Contribution of surface diffusion to diffusion flux within the macropores was found to be quite significant. Also, it was found that ...
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Supercritical fluid extraction has been used to recover biomaterials from natural matrices. Mathematical modeling of the extraction is required for process design and scale up. Existing models in literature are correlative and dependent upon the experimental data. Construction of predictive models giving reliable results in the lack of experimental data is precious. The long term objective of this study was to construct a predictive mass transfer model, representing supercritical fluid extraction of biomate...
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The extraction procedures for the determination of polycyclic aromatic hydrocarbons (PAH) concentrations in sediment samples had been developed by using GC-FID and GC-MS. The optimized methods were soxhlet extraction, ultrasonic bath extraction and solid phase micro extraction (SPME). In order to search out the main factors affecting extraction efficiencies of the methods, factorial design was used. The best extraction method was chosen and optimum values for main factors were selected for the development o...
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Citation Formats
G. DOĞU and T. Doğu, “Fifty Years of Moment Technique for Dynamic Analysis of Chemical Reactor Parameters,” INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: