Alkaline Ph Measurement Errors in Reactive Dye Bath Operations
Uncorrected sodium ion interference and junction drift in high-alkaline reactive dye baths distort pH readings by up to 0.6 units, causing dye hydrolysis and batch off-shade failures.
Glass Electrode Error
Measurement Discrepancy
Electrochemical sensors used to measure dye bath acidity can deviate from true values under extreme chemical conditions. Such deviation is often caused by glass electrode error during high-alkalinity processing. This discrepancy leads to incorrect chemical dosing in the finishing department.
Continuous monitoring reduces the chance of fabric damage. Corrective actions must be taken when the electrode response becomes non-linear in concentrated sodium salt solutions.
Sodium Interference
Alkali ions like sodium can substitute for hydrogen ions on the hydrated gel layer of the probe. This sodium ion presence causes a negative glass electrode error where the recorded pH is lower than the actual value. This phenomenon becomes prominent in reactive dyeing baths containing high concentrations of sodium chloride or soda ash.
Dehydration Effect
Storing the probe in dry conditions or exposing it to concentrated alcohol solutions reduces the thickness of the responsive silica gel layer. Without adequate hydration, the sensor cannot generate a stable electrical potential. Rehydration in a dilute acid solution restores the responsive layer over several hours.
Calibration Correction
Frequent calibration using dual buffers helps compensate for minor changes in probe sensitivity. Technicians must replace the electrode when the response becomes sluggish or when the calculated slope drops below ninety-five percent. Proper maintenance ensures the reliability of pH measurements in wet finishing.