Abstract
Acetaldehyde diethyl acetal (herein called acetal) is an important pollutant of anhydrous ethanol. Isobaric vapor–liquid equilibrium (VLE) of an ethanol–acetal binary system was measured using a vapor condensate and liquid circulation VLE still. The experimental data were correlated with Wilson, nonrandom two-liquid (NRTL), and universal quasichemical (UNIQUAC) activity coefficient models, which were found suitable for representing the VLE data. Proper agreements between experimental and calculated VLE data were obtained, which were then confirmed with consistency tests. The applicability of the novel VLE data was demonstrated during an investigation of an anhydrous ethanol purification column. Reduction of the concentration of acetal and other pollutants was examined and optimized in a flowsheet environment. The modeling results were verified in a laboratory with an experimental distillation column, confirming a correct agreement between the results. It must be highlighted that the developed method is suitable for the production of pharmacopeial quality anhydrous alcohol, based on reliable, verified VLE data. The results show the importance of accurate VLE data in critical compositions (low pollutant content); moreover, aiming at high product purity, experimental validation has paramount importance. The consistency between the three platforms (VLE and distillation experiments and flowsheet simulation) confirms the accuracy of the developed method.
Highlights
Certain industries, for example, pharmaceutical and fine chemical sectors, need high purity chemicals
The results show the importance of accurate vapor−liquid equilibrium (VLE) data in critical compositions; aiming at high product purity, experimental validation has paramount importance
The modified equipment and VLE measurement procedure were tested with the acetaldehyde−ethanol binary mixture as a well-known and studied system
Summary
For example, pharmaceutical and fine chemical sectors, need high purity chemicals. Such chemicals are frequently produced by distillation. The process design activities are strongly based on professional flowsheeting software programs. These software programs must operate on a reliable database, rigorous modeling tools, and accurate calculation based on thermodynamic equilibria. The accuracy of these tools is generally sufficient; in a research focused on obtaining high purity chemicals, special attention must be paid to the evaluation of the computed results
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call