Effects of L‐Serine and L‐Proline on Crystallization Kinetics of Calcium Pyrophosphate Dihydrate

Calcium pyrophosphate dihydrate (CPPD) crystallization was investigated in a mixed‐suspension mixed‐product removal (MSMPR)‐type crystallizer in the presence of the amino acids L‐serine and L‐proline as additives. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and zeta potential analysis were applied for characterization of the crystals obtained. CPPD crystals obtained in pure media consisted of aggregated particles which included plate‐like structures and rod‐shaped crystals. However, it was observed that agglomeration and breakage tendency on CPPD crystals obtained in the presence of amino acids were remarkable. The population balance equation for CPPD crystals was resolved with numerical analysis considering aggregation and breakage steps. The predominant mechanism was the breakage for CPPD crystallization in the presence of amino acids. Crystallization of calcium pyrophosphate dihydrate (CPPD), which causes pseudogout disease in joints, was studied in the presence of Ser and Pro as additives. The size and habit of the crystals in the presence of amino acids were changed significantly. A population balance equation was resolved, and as predominant mechanism the breakage for CPPD crystallization in the presence of Ser and Pro was identified.