Most instruments use a polarized dual platinum electrode to measure voltage. After a certain period of use, some of the Karl Fischer reagents and samples will invalidate the electrode response, the endpoint recognition delays, and the endpoint color will turn brown instead of yellow. Now the electrodes must be cleaned. When cleaning, the electrode is usually placed in an ultrasonic cleaning bath with deionized water or ethanol for several minutes; or in chromic acid for 60s'' and then rinsed with deionized water or ethanol (dry before use).
Contaminant type and its cleaning method.
Types of contaminants Cleaning agents Fat oils Mixtures of chloroform and toluene Polar substances Dimethylformamide Salts Carboxamide Resins Macromolecules Alcohols Acetone Diethyl ether pigments Substances Diluted bleaches (3) Under normal conditions'' The drift of the instrument is a few microliters per minute (referring to the amount of Karl Fischer reagent consumed in unit time in order to keep the titration cell dry; this reagent is used to titrate the water in the titration cell on the one hand''. On the other hand, it compensates for the consumption of iodine caused by slow side effects.) If the drift value increases, you must check the instrument's tightness or consider regenerating the molecular sieve. During regeneration, the molecular sieves are dried in a drying oven at 160-300° C. for at least 24 h. The molecular sieve installed on the waste bottle must be cleaned with distilled water before regeneration because it contains water and sulfur dioxide.
(3) The buret is washed with absolute ethanol solution. Do not place the burette above 40°C.
(4) The instrument must be placed in a dry and clean environment'' and arranged for safekeeping; if not used for a long period of time, all the reagents in the instrument must be withdrawn'' and all lines should be cleaned'' and air dried.
The general sample can be selected by Guanya Moisture Analyzer to measure the moisture. The operation is simple and the measurement is convenient.
Contaminant type and its cleaning method.
Types of contaminants Cleaning agents Fat oils Mixtures of chloroform and toluene Polar substances Dimethylformamide Salts Carboxamide Resins Macromolecules Alcohols Acetone Diethyl ether pigments Substances Diluted bleaches (3) Under normal conditions'' The drift of the instrument is a few microliters per minute (referring to the amount of Karl Fischer reagent consumed in unit time in order to keep the titration cell dry; this reagent is used to titrate the water in the titration cell on the one hand''. On the other hand, it compensates for the consumption of iodine caused by slow side effects.) If the drift value increases, you must check the instrument's tightness or consider regenerating the molecular sieve. During regeneration, the molecular sieves are dried in a drying oven at 160-300° C. for at least 24 h. The molecular sieve installed on the waste bottle must be cleaned with distilled water before regeneration because it contains water and sulfur dioxide.
(3) The buret is washed with absolute ethanol solution. Do not place the burette above 40°C.
(4) The instrument must be placed in a dry and clean environment'' and arranged for safekeeping; if not used for a long period of time, all the reagents in the instrument must be withdrawn'' and all lines should be cleaned'' and air dried.
The general sample can be selected by Guanya Moisture Analyzer to measure the moisture. The operation is simple and the measurement is convenient.
Basic Red dyes, Cationic Red China Manufacturer for acrylic dyeing, inks and paper, Basic red 46,Basic Red 12, Basic red 14, Basic red 1, Basic red 1:1,Basic red 51 etc.
Basic dyes can be used for silk, wool and cotton with a mordant, they are also used on basic-dyeable acrylics, nylons, polyesters and paper industry, on which they exhibit reasonably good fastness.
Basic Red dyes, Cationic Red China Manufacturer for acrylic dyeing, inks and paper, Basic red 46,Basic Red 12, Basic red 14 etc.
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