APPARATUS FOR DETERMINING CONCENTRATION OF OXYGEN IN AQUEOUS AND GASEOUS MEDIA Russian patent published in 2012 - IPC G01N27/49 

FIELD: chemistry.

SUBSTANCE: apparatus for determining concentration of oxygen in aqueous and gaseous media has an electrically insulating housing in which there is an anode and a cathode with current leads, fixed with respect to each other, an oxygen permeable membrane which separates the anode and the cathode from the analysed medium, a latch which holds the membrane, one side of which lies in the immediate vicinity of the cathode and the other side lies in the immediate vicinity of the analysed medium, a current source and a means of measuring electrical current between the anode and the cathode. According to the invention, the housing is detachable and consists of three parts, one of which is the central part which has a cylindrical cavity; on one side of the central part of the housing there is a cover with a hole for inlet of electrolyte which is connected to a rod lying inside the central part of the housing with clearance from the wall of the cavity and having a system of electrodes comprising a cathode in form of a metal coating with the shape of a solid circle on the end face of the cylindrical rod; the lateral surface of the rod has a comparison electrode in form of a metal coating whose surface area is at least 10 times greater than the surface area of the cathode from which the comparison electrode is separated by a porous spacer, and the latch which holds the membrane has a depression filled with the analysed medium, lying on the side of the membrane and at the centre of the latch with a depth whose value is not less than the distance between the membrane and the cathode and is not more than 3 mm; the latch has two holes for inlet and outlet of the analysed medium, and the surface area of the membrane is greater than the surface area of the cathode by not more twice.

EFFECT: shorter analysis time and lower labour input, high accuracy and sensitivity of determining concentration of oxygen, cheaper apparatus compared to existing apparatus.

4 cl, 4 dwg, 1 tbl, 4 ex