Abstract: The present invention concerns a process for the recovery and purification of glyoxylic acid from a process stream comprising glyoxylic acid and oxalic acid, wherein the process stream comprising glyoxylic acid and oxalic acid is subjected to a number of alternating separation and dehydration steps. The process comprising the steps of: (i) providing an aqueous solution comprising glyoxylic acid and oxalic acid; (ii) precipitating at least a portion of the oxalic acid using low-temperature crystallization at a temperature of at most 18° C.; (iii) separating the precipitated oxalic acid from the solution to obtain a solution depleted in oxalic acid; (iv) concentrating the solution depleted in oxalic obtained in step (iii) using reverse osmosis; and repeating steps (ii)-(iv) with the concentrated solution obtained in step (iv) until a purified glyoxylic acid stream with a predetermined degree of purity is obtained. The invention also relates to a system for carrying out the process.

Abstract: The invention relates to a gas-diffusion electrode provided with a sintered and cast gas-diffusion layer having a high elastic modulus. The electrode is useful as hydrogen-consuming anode or oxygen-consuming cathode of depolarised electrolytic cells such as electrowinning, chlor-alkali or electrodialysis cells.