The Electrodialytic Production of Sodium Methylate by Methanol Dissociation

Bipolar membranes may be used not only for the electrodialytic dissociation of water. They can also be applied for the dissociation of alcohol and thus for the production of alcoholates, as illustrated in the following example. Methanol, like water, is both a weak base and a weak acid. Its dissociation constant, however, is somewhat less than that of water. Thus, sodium methanolate can be efficiently produced from methanol and sodium acetate in nonaqueous media by the use of bipolar membranes

Figure 7 Schematic diagram illustrating a continuous fermentation process for the production of itaconicacid without further addition of acids or bases using bipolar membranes.

according to the reaction scheme illustrated in Figure 8, which shows a bipolar membrane elec-trodialysis stack consisting of two compartment cell systems in a repeating unit between electrodes. Water-free methanol and sodium acetate are fed into the cell formed by the bipolar and the cation exchange membrane which is directed towards the cathode while water-free methanol is passed through the other cell. Under the driving force of an electrical potential gradient, methanol is split in the bipolar membrane into protons and CH3O" ions which react with sodium ions migrating from the sodium acetate-

containing cell to form CH3ONa. The acetate ions recombine on the other side of the bipolar membrane with the protons which were produced simultaneously with the CH3O" ions in the bipolar membrane to form acetic acid. Thus, sodium acetate and methanol are converted into sodium methanolate. The current efficiency decreases with increasing methylate concentration due to proton transfer from the acetic acid-containing compartment through the bipolar membrane to the sodium methanolate-containing cell. But all in all the process seems to be technically feasible.

Figure 8 Schematic diagram illustrating the electrodialytic production of sodium methanolate from methanol and sodium acetate in bipolar membranes containing a two-compartment cell unit.
Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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