Selective solvent evaporation from binary mixtures of water and tetrahydrofuran using a falling film microreactor

Abstract

In this work, a falling film micro reactor was investigated regarding its ability to continuously eliminate tetrahydrofuran (THF) out of a THF-water mixture via nitrogen stripping. Mass transfer measurements were performed at different temperatures and flow rates. The residual content of THF in the eluate was quantified with high precision (<0.1%) via density measurements. Remarkably, complete elimination of THF could be achieved for liquid volume flow rates smaller than 2 ml/min and nitrogen volume flow rates larger than 400 ml/min at all three investigated temperatures (55°C, 60°C, and 65°C). In order to assist future design processes of such binary microstripping systems, we further developed a mass transfer model for this separation process extending an existing model for evaporation of a pure liquid. The good agreement of experimental data and calculations in the overall investigated parameter range (≤20%, for gas flow rates below 500 ml/min ≤11%) shows the potential of the model for the prediction of alternative operational parameter settings, e.g. at different THF entrance concentrations

Formulation of Next‐Generation Multicompartment Microcapsules by Reversible Electrostatic Attraction

“…Droplets with a diameter of around 1 μm, which consisted of chloroform, eucalyptus oil and PLLA or PLGA, were formed this way. The evaporation of chloroform took place in the pre‐heated falling film micro reactor at 58 °C and with nitrogen as carrier gas [19] . Upon evaporation of solvent, the used polymer precipitated at the interface of the droplets and formed the nanocapsules shell with eucalyptus oil as a core.…”

“…The evaporation of chloroform took place in the pre-heated falling film micro reactor at 58°C and with nitrogen as carrier gas. [19] Upon evaporation of solvent, the used polymer precipitated at the interface of the droplets and formed the nanocapsules shell with eucalyptus oil as a core. PLLA and PLGA nanocapsules showed homogeneous size distribution with an average size of 115 � 21 and 145 � 21 nm, respectively.…”

Modular Manufacturing Platform for Continuous Synthesis and Analysis of Versatile Nanomaterials

“…As published , the stripping of tetrahydrofuran (THF) from a THF/water mixture, enhanced by convective nitrogen flow as a carrier gas in a falling‐film microreactor (FFMR), has been investigated. Furthermore, a mass transfer model for the separation process and the prediction of alternative operational parameter settings was developed based on an existing model for evaporation of a pure liquid , .…”

“…For the experiments, an FFMR developed by the Fraunhofer IMM was used. The microstructured plate consists of five channels with a length of 25.5 cm, a width of 1.2 mm, and a height of 0.4 mm; the channels are brought together at the bottom of the plate to combine all liquid streams before leaving the reactor , .…”

Tuning pore size and density of rigid polylactic acid foams through thermally induced phase separation and optimization using response surface methodology

“…This limitation is important to prevent the solvent from boiling off during the heating process, which could negatively impact the formation of crystallites in the polymer. Maintaining the solution temperature below this threshold ensures that the polymer chains have sufficient time to reorganize and form stable crystalline structures without the risk of solvent loss 35 .…”