Does anyone have experience regarding terephthalic acid analyses from the solid tar? Which instrumentation have you used for the analyses and how you have prepared the samples? Thanks in advance!
Nowadays, the best method for the analysis of tetraphthalic acid and similar compounds is by HPLC. The sample should be dissolved in solvent which dissolves tetraphthalic acid such as alkali or mixture of alkali/MeOH.
The following publications describes the analysis of tetraphthalic acid by HPLC and depicts the solvents to be used for the sample preparation.