Errors were discovered concerning the published equation coefficients of Zhao and co-workers [J. Chem. Thermodyn. 57 (2013) 9-13] for mathematically describing the solubility of tetracycline hydrochloride (TCH) in methanol, ethanol, 1-propanol, 1-butanol, acetone and acetonitrile by using the NRTL model. The curve-fit coefficients fail to describe the reported solubility data in the authors' published paper. The equation parameters were re-analyzed based on the reported solubility data. (C) 2018 Elsevier Ltd.