Polarographic study of inhibitors and catalysts for the reaction of dissolved oxygen with sulphite ion

Investigations into the Speciation of Inorganic Arsenic in Weakly Alkaline Medium by Voltammetry

“…It was shown that the reaction proceeds via a radical‐chain mechanism and depends on both the pH and the purity of solutions, being accelerated in the presence of various transition metal ion impurities (copper, cobalt etc.) or inhibited by various organic impurities 26, 27.…”

“…Published data indicates that the reaction of oxygen with sulfite is a complex radical chain process that depends on many factors ‐ pH, impurities, catalysts or inhibitors, etc. 26, 27. This reaction is commonly used in Industry for creating anticorrosive conditions; in the food industry sulfites are used as antioxidants and an antibacterial agent 28.…”

Phosphines as Efficient Dioxygen Scavengers in Nitrous Oxide Sensors

“…The issue of dioxygen as interfering species is restricted not only to N 2 O, but also in the case of electrochemical detection of nitrate and nitrite, , where dioxygen scavenging is also key to successful sensor operation. Methods to remove dissolved dioxygen in amperometric applications include the usage of alkaline ascorbate solution, enzymes, sulfite, and thiosulfate, and by bacterial consumption in, e.g., NO x – /NO 2 – microsensors. , The techniques are, however, only applicable to aqueous solutions of the dioxygen scavenger. Additionally, since the polarization potential required for the electroreduction of N 2 O is also high enough to reduce water, the aqueous dioxygen scavenger must be situated in a chamber physically separated by a membrane. , The design of such a two-chamber sensor is shown in Figure (also see Figure S-1 in SI).…”

“…The issue of dioxygen as interfering species is restricted not only to N 2 O, but also in the case of electrochemical detection of nitrate and nitrite, 7,8 where dioxygen scavenging is also key to successful sensor operation. Methods to remove dissolved dioxygen in amperometric applications include the usage of alkaline ascorbate solution, 4 enzymes, 7 sulfite, 9 and thiosulfate, 10 and by bacterial consumption in, e.g., NO x − /NO 2 − microsensors. 11,12 The techniques are, however, only applicable to aqueous solutions of the dioxygen scavenger.…”

Studies of reverse pulse amperometry at mercury electrodes and its application for cation-exchange chromatography

“…This is accomplished, most commonly, by simply purging the solution for 10-15 min with a pure, inert gas such as nitrogen, helium, or argon (42). In addition, re ducing agents, such as sodium sulfite (42)(43)(44) and ascorbic acid (45), or an enzyme such as glucose oxidase (46), have been used for removing the dissolved oxygen. For the analytical system, based on use of a flowthrough polarographic detector in conjunction with high performance liquid chromatography (HPLC), removal of dis solved oxygen becomes more complicated than for conventional polarography.…”