Fig. 6From: From beech wood to itaconic acid: case study on biorefinery process integrationOperation of pH-shift crystallization. Solubility of itaconic acid (IA) as a function of pH value as well as in presence of citric acid (CA) buffer as a function of pH value and temperature, determined by excess method and HPLC analysis. The vertical line marks the lower pKa1 value of itaconic acid at pH 3.84. The pH was readjusted after 2 h by the addition of (45 wt%) sodium hydroxide solutionBack to article page