![]() Such short time of exposition sufficed the photo C–H chlorination. carbonate was introduced to the reactor, the residence time was measured to be 15 or 30 s, depending on the slope of the reactor set at 15 or 5°, respectively. The setup employed sloped channels so as to make the liquid phase thinner, ensuring a high surface-to-volume ratio. A novel photoflow setup designed for a gas–liquid biphasic reaction turned out to be useful for the direct use of chlorine gas. We report the high-speed C–H chlorination of ethylene carbonate, which gives chloroethylene carbonate, a precursor to vinylene carbonate. The analysis performed by means of combined application of dilatometric, impedance and XPS techniques reveals the positive role of VC for improving the electrochemical-mechanical properties of the graphite porous anode. This leads to a continuous incorporation of decomposition products in the composite layer during the subsequent cycles and related to this additional irreversible volume expansion. In contrast to the VC containing electrolyte, the passivation layer formed on the anode in the absence of VC cannot effectively terminate the electroactivity of the graphite surface and the electron charge transfer. The observed behavior is associated with differences in the decomposition mechanism of the electrolyte components and their reaction kinetics, influenced by the presence of VC. With the increase of VC amount in the electrolyte the irreversible dilation decreases significantly, showing that the addition of VC has a positive effect on the mechanical performance of the battery. While the reversible dilation of the anode coatings is not influenced by the VC concentration the irreversible part displays a strong dependence. The volumetric expansion of graphite composite electrodes for Li ion battery is investigated by electrochemical dilatometry in electrolytes with different concentration of vinylene carbonate (VC). Model for the TDI chlorination including by-product formation was suggested and used to predict product selectivity at full TDI conversion. Based on the microreactor data, a kinetic The space-time yield of 1Cl-TDI achieved in the microstructured reactor (400 mol l?1 h?1) clearly exceeded the performance of the batch reactor (space-time yield 1.3 mol l?1 h?1). The microstructured reactor led to remarkably higher selectivities than the conventional batch reactor, where the selectivity to 1Cl-TDI was only 45% at 65% TDI conversion and the side product 5Cl-TDI was formed with 50% selectivity. Were formed and the selectivity to 1Cl-TDI was lowered. In presence of a Lewis acid such as FeCl3, formed by chlorination using a reaction plate made of iron, consecutive products The influence of the reactor material was shown. Of consecutive products increased and the selectivity to 1Cl-TDI decreased to 67% after 14 s residence time. The yield of 1Cl-TDI was enhanced by increasing the residence time from 24% after 5 s to 54% after 14 s. (1Cl-TDI) achieved a value of 80% at 55% TDI conversion, whereas the side product toluene-5-chloro2,4-diisocyanate (5Cl-TDI) was formed with only 5% selectivity. In the microstructured reactor the selectivity to the side-chain chlorinated product 1-chloromethyl-2,4-diisocyanatobenzene The advantageous application of a falling-film microreactor for a photochemical gas/liquid reaction was demonstrated by the selective photochlorination of toluene-2,4-diisocyanate (TDI). We found that the contaminated water negatively influenced the performance of the C-H chlorination. At a higher conversion of ethylene carbonate such as 63%, the selectivity for mono-chlorinated ethylene carbonate over di-chlorinated ethylene carbonate was 86%. The 100% selectivity for single chlorination required the low conversion of ethylene carbonate such as 9%, which was controlled by limited introduction of chlorine gas. We also found that the contaminated water negatively influenced the performance of C-H chlorination. The partial irradiation of the flow channels sufficed for the C-H chlorination, which is consistent with the requirement of photoirradiation for the purpose of radical initiation. ![]() Such short time exposition sufficed the photo C-H chlorination. When ethylene carbonate was introduced to the reactor, the residence time was measured to be 15 or 30 sec, depending on the slope of the reactor to be 15 or 5 ☌, respectively. ![]() The setup employed sloped channels so as to make the liquid phase thinner, ensuring high surface to volume ratio. A novel photoflow setup designed for a gas-liquid biphasic reaction turned out to be useful for the direct use of chlorine gas in flow. ![]() We report flash C-H chlorination of ethylene carbonate, which gives chloroethylene carbonate, a precursor to ethylene carbonate.
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