Calorimetric method for determining and regulation of the per acid content of a solution in the presence of hydrogen peroxide

摘要

According to the invention, the peracid content is adjusted in the presence of hydrogen peroxide in a solution (2) with a molar concentration ratio of hydrogen peroxide/peracid no higher than 100 by a process in which a pump (3) is used to draw a diluting and/or pH adjusting liquid (9) simultaneously into the intake circuits of two pumps (5, 6) operating at the same flow rate, said pump (5) supplying its measuring tank (8) and the flow rates of pumps (3, 5, 6) adjusted so that the peracid concentration in the flow to be measured is lower than about 100 ppm by weight, to the measuring flow (10) from the pump (6) is added an excess of iodide (11) by means of a pump (13) and a measuring unit (14) to which are connected the cells of the photometer compares the intensity of the iodine colour formed in the measuring tank (8) with the reference in the reference tank (7) and transfers the difference to a regulator (16), which, if necessary, actuates a pump (19) injecting a peracid solution (20) into the solution (2). Application especially to the determination and regulation of the peracetic acid content in industrial disinfectant solutions.