# One-Dimensional Modeling of Mass Transfer Processes in an Annular Centrifugal Contactor

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## Abstract

**:**

## 1. Introduction

## 2. Methods and Materials

^{1}H-NMR was used to determine the concentrations of the components. For that, an NMR spectrometer from Magritek, type Spinsolve SPA345, was used in continuous and batch measurement mode. For continuous measurement mode, another peristaltic pump (Reglo Digital, Ismatec) was used to produce a continuous stream of aqueous outlet flow of the ACC. This flow was guided via a PTFE hose through a flow cell in the spectrometer and analyzed every 30 s. Batch measurements were conducted by collecting samples of the outlet flows in sampling tubes, which were directly measured in the spectrometer. Integrals of the solvent and transferred components were calibrated with binary mixtures of five concentrations in the expected range.

## 3. Results

#### 3.1. Definition of the Boundaries of the Balance Sheets

#### 3.2. Creation of the Model Equations

#### 3.3. Estimation of Parameters Contributing to Mass Transfer

^{−9}m

^{2}/s are consistently underestimated. The underestimated diffusion coefficients have in common that they are for diffusion in a solvent with low polarity.

#### 3.4. Validation of Simulated Results with Experimental Data

## 4. Model Validation and Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

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**Figure 1.**Section view of a schematic ACC with the four balance sheet compartments marked as dash-dotted rectangles.

**Figure 2.**Comparison of the concentration profiles for an exemplary ACC simulation resulting for different ODE solver methods.

**Figure 3.**Comparison of published datasets for experimental diffusion coefficients D

_{exp}(taken from Misek [10] and Berger [11]) with their corresponding estimated diffusion coefficients D

_{est}using the methods of Einstein, Sutherland and Edward (the target line corresponds to a deviation between experimental and estimated diffusion coefficients of zero).

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**MDPI and ACS Style**

Ritzler, P.M.; Weiss, C.K.; Seyfang, B.C.
One-Dimensional Modeling of Mass Transfer Processes in an Annular Centrifugal Contactor. *ChemEngineering* **2023**, *7*, 59.
https://doi.org/10.3390/chemengineering7040059

**AMA Style**

Ritzler PM, Weiss CK, Seyfang BC.
One-Dimensional Modeling of Mass Transfer Processes in an Annular Centrifugal Contactor. *ChemEngineering*. 2023; 7(4):59.
https://doi.org/10.3390/chemengineering7040059

**Chicago/Turabian Style**

Ritzler, Peter M., Clemens K. Weiss, and Bernhard C. Seyfang.
2023. "One-Dimensional Modeling of Mass Transfer Processes in an Annular Centrifugal Contactor" *ChemEngineering* 7, no. 4: 59.
https://doi.org/10.3390/chemengineering7040059