0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login to access the full content or check if you have access via
6.2.2 Bipolar Stacked Cells

DOI: 10.1055/sos-SD-236-00125

Villani, E.; Inagi, S.Science of Synthesis: Electrochemistry in Organic Synthesis, (20211159.

In 1965, Monsanto started to commercialize a process based on bipolar electrochemistry for the reductive electrohydrodimerization of acrylonitrile to adiponitrile, an intermediate in the manufacture of Nylon 66 (see Scheme 1).[‌6‌] Even if the principle of cathodic hydrocoupling of acrylonitrile had already been known since the 1940s, it was only at the beginning of the 1960s that Baizer discovered the use of quaternary ammonium salts as supporting electrolytes to improve the yield and current efficiency of the coupling reaction.[‌28‌] Therefore, this synthetic process is called the Baizer–Monsanto process, or simply the Monsanto process. It is carried out in a bipolar cell of simple design (Figure 7, b), consisting of a bipolar stack of carbon steel sheets whose cathode faces are smoothly electroplated with cadmium to a thickness of 0.1 to 0.2 mm.[‌29‌] The anode–cathode gap is fixed at 2-mm distance by plastic spacers in a pressure vessel, and the electrolyte is fed uniformly across the parallel interelectrode gaps. The emulsion is recycled through the cell from a reservoir and a fraction of the organic phase is removed continuously for extraction of the product. This process is still in operation today, with a volume capacity of hundreds of thousands of tons per year worldwide.[‌30‌]

Meeeee 8 Mee Meeee ee Meeeeee Meeee Meeee: MMMM Meeeeeeee Mee Meee[‌88‌] eee Meeeeeee Meeeeee Meeee Meeeeee[‌8‌]

Meeeeeeeee eeee eeeeeeeeeeeee eeee (e) (Meeeeeeee; Meeee, ee Meeeeeeeeeeeeee Meeeeee Meeeeeeeeee), Meeeeeeee (8888), e 888 eeee eeeeeeeeee eeee Meeeeeee eee (e) (Meee; Meeeee; Meeeee, Mee.; ee Meeeeeeeeeeeeee Meeeeeeeee, 8ee eeeeeee), Meeeeeeee (8888), ee 88–88 eeee eeeeeeeeee eeee Meeeeeee.

Mee eeeeeeeee eee eeee ee e eeee-eeeee eeee eeee eee eee eeeee eeeeeeee eee eeeeeeeeeeee ee MMMM eeeeee eee eee ee eee 8888e[‌88‌] ee ee eeeeeeeeeee ee eee eee ee e eeeeeeeeeee eeeee ee ee eeeeeeeee. Mee eeee eeeeeeee ee e eeeee ee eeeeeeeeeeee eeeeeee eeeeeeee eeee eeeeee (eeeeeeee) eeeeeee ee eeeeeeeeee ee e eeeeeeeeeee eeeee eeeee (Meeeee 8, e). Meee eeeeeee eeeeeee eeeee eee eeeeeeeee ee eeeeee eeeeeeeeeeeeee eeee (8–8 ee), eee eee eeeeeeeeeee ee eeeeee eeeeeee eeee eee eeee eee eeeee eeeeeeee eeeeeee eeeeeee eee eeeee. Meee eeeeeeeeeeeee eeeeee eee eeeee eeeeeee eeee ee eeeeee eeeeeeeeee eeeeeeeeeeee ee ee eeeeeeeee eee eee eeeeeee eeeeeeeeee eeeeee eee eeeeeeeeeeeeeee eeeeeeeee ee ee eeeeeeeee. MMMM eee eeee eee eeee ee e eeeeee ee eeeeeeeeeeeeee eeeeeeeee eeeeeeeee, eeeeeeeee eee eeeeeeeeeeeeeeee ee eeeeeeeeeeee (8)[‌88‌] eee 8-eeeeeeeeeeeeeeeeeee eeeeeeee eeeeee (8)[‌8‌] (Meeeee 8), eee eee eeeeee eeeeeeeeeeeeeeee ee eeeeeeeee (8) eee eeee-eeeeeeeeeeeeeeeee eeeeeeee eeeeee (8)[‌88‌] (Meeeee 8).

Meeeee 8 Meeeee Meeeeee Meeeeeeeeeeeeeee Meeeeee eee eee Meeeeeeeeeee Meeeeeeeee ee Meeeeeeee eee eeee-Meeeeeeeeeeeeeeee Meeeeeee Meeeee[‌88‌]

Meeeeeee ee MMMMʼe eeeeeeeeee, eeeee eeeeeeeee eee eeeee eeee eeee eeeeeeee ee eee eeeeeeeeee eeee eeeeeeeeeeee ee eeeeeeeee eeeeeeeeeeeeee eeeeeeeee.[‌88‌,‌88‌]

Mee 8M Meeeeee eee eeeeeeeee e eeeeeee eeeeeeeee eeeee eeeeeee eee eee eeeeeeeeeeeeeee ee e eeeeeee ee eeeeeee eeeeeeeee eeeee ee eeeeeeeeeee eeeeeeee ee eeeeeeeee eeeeee eeeeeeee eeeeeeee (MM).[‌88‌] Mee eeeeeee eeeeeee ee eeeeeeeee ee eeeeeee eeeeeeeeeeeee eeeeeeee, eeeeee-eeeee eeeeeeeeee eeee ee ee eeeeeeeeeeee eeeeeeeeee eeeeeeee, eeeeeeeee eeeeee, eeeeeeee ee eeeeee e eeeeee ee e eeeeee-eeeeeeee eeeeeeeeee eeeeeeeeeeeee. Mee eeeeee eeeeeee eeeeeeeeee eeeeeeeee eeeeeeee eeeeeeee eee eee eeeeeeeeeeeee eeeeeee eeeeeeee, e.e. eeeeeeeeeeeeee, ee eeeeeeeeee ee eeeeee eeeeeeeeee eeeeeee eee eeeeeeeeee, ee e eeeeeeeeeee eee eeeeeeee ee eeeee ee eeeeeeeeeee eeeeeeeeee eeeeee eeeee ee eeeeeeeeee. Meeeee eeeeeeee ee eeeeeeeeeee eeeee ee eeeeeeeee eeeeeeee eeeeeeee eee, eeee eeee ee ee eeeee, ee eeeeee eee eeeeeeeeeeeeeee eeeeeeeeeeee; ee ee eeeeeeee ee eeee e eeeeeeeeee eeeee ee MeM88−, eeeee eeee ee ee eeeeeeeee eee eeeeeeeeeee eeeeeeeeeeee eeeee. Me eee eeeeeee, eeeeeeee ee eee eeee eeeeeee. Meeeeeeeeeeeee eeeeeeeeee eeeee, eeee ee eeeeeeeeeeeeeeeee eeee, eee eeeeeee eee eeeeeeeeeee eeeeeeee.[‌88‌]