The reaction of hydrochloric acid with dry alkaline sorbents such as hydrated lime in the incineration units leads to the formation of not only calcium chloride but calcium hydroxichloride as well. A thermodynamic study of the chemical reactions involved in the dechlorination process is required in order to show if such a product is theoretically possible to be formed. However, the data of CaClOH necessary to carry out such a study are not available in the literature. Hence, a method of predicting these data is developed in the present work. Predicted values of Gibbs energy and entropy of formation of CaClOH at different temperatures are compared to values calculated by Mostafa＇s model and satisfactory results were obtained.