One of the methods for determining residual anthraquinone in cooking waste liquor is spectrophotometry. Here are the steps of the method:
Sample preparation: Filter the cooking waste to obtain an impurity-free solution.
Establish a standard curve: Take a certain amount of anthraquinone standard (such as 0, 5, 10, 20, 40, 60mg/L), add it to a series of test tubes, and add an appropriate amount of ethanol to dissolve. Use a Spectrophotometer to measure the absorbance value at each concentration at 343nm to establish a standard curve.
Determination of the sample: measure the absorbance value of the sample at 343nm with a Spectrophotometer , and calculate the concentration of anthraquinone according to the standard curve.
Precautions:
The Spectrophotometer should be zero adjusted to ensure accurate readings.
A photometer with an appropriate wavelength range should be selected for measurement to ensure data accuracy.
During operation, dust and impurities in the air should be avoided from affecting the results.
