Search: active ingredient concentration rate

Alkaline cleaning solutions, especially for automatic bottle cleaning, consist of sodium hydroxide and so-called active ingredient concentrates. Concentration losses caused by carryover or carbonization can be determined by determining the alkaline component in accordance with
T-740.01.041 Electrolytic conductivity of acidic and alkaline cleaning agents
T-741.02.032 Alkaline cleaning agents - sodium hydroxide only
T-741.03.032 Alkaline cleaning agents containing carbonate - sodium hydroxide and soda
T-741.04.023 Alkaline cleaning agents containing carbonate in the presence of phosphates and soiling - sodium hydroxide and soda
T-741.05.032 Alkaline cleaning agents containing aluminum - sodium hydroxide, aluminum
T-741.06.032 Alkaline cleaning agents containing aluminum - sodium hydroxide, aluminum, soda
can be controlled. However, the active ingredient concentrates are only recorded if it is ensured that the required concentration of the desired active ingredient has been added or dosed using appropriate dosing equipment (proportional dosing). If this is not the case, i.e. if the active ingredient concentrates are prepared and dosed manually, a separate check of the active ingredient concentration is advisable. The determination methods are very different and are specific to a particular active ingredient concentrate*. The method should be requested from the manufacturer.

* e.g. P 3-stabilon; Henkel Hygiene GmbH, D-40554 Düsseldorf, https://www.henkel.de/

For determination of the dry residue in water after filtration, a certain quantity of filtrate is evaporated until dry. It is subsequently dried in a drying oven to eliminate any remaining moisture.

Determination of the dry residue (ash content) of a filtered or unfiltered water sample.

In an acidic sulfurous solution containing phosphorus, nitrate ions react with 2,6-dimethylphenol to produce 4-nitro-2,6-dimethylphenol.

The method is suitable for determining approx. 0.5–25 mg/l NO₃^-. If the ratio of chloride to nitrate ions is larger than 10, this may interfere with the reaction (if this is the case, according to DEV D 9-3, follow DIN 38405); likewise, nitrite ions exceeding approx. 0.2 mg/l may also interfere with the reaction. For their removal, refer to Remarks below.

Alkaline cleaning agents and disinfectants containing chlorine can be determined by their alkalinity concentration. The chlorine present destroys most indicators by oxidation. Before adding the indicator, the chlorine must be eliminated by adding sodium thiosulphate to the sample.

Separation by HPLC is based on a combination of reversed-phase, normal-phase, ion-exclusion and ion-exchange chromatography