Impact of surface temperature on CaSO4 deposition from surface energy perspective

•Substantial increase of acid-base interaction energy with surface temperature•Reduction of Lifshitz-van der Waals interaction energy with surface temperature•Spreading coefficient better interpolates dependency of deposition on temperature•Surface energy-based correlation for prediction of CaSO4 deposition propensity•Impact of surface temperature on coagulation to precursors While numerous surface energy-based studies have investigated various aspects of CaSO4 deposition on modified surfaces, the impact of surface temperature though, as a dominant parameter, has not thoroughly been characterized from surface energy perspective. This has led that most previous studies have attained surface energy specifications at ambient temperature for utilization at elevated operating temperatures. The present study examines the impact of surface temperature in the range of 293–368 K, but at a constant bulk temperature less than surface temperature, on surface energy and its sub-components of several metallic surfaces and amorphous carbon-based coatings. Moreover, the influence of surface temperature on the energy of adhesion between CaSO4 precursors and these surfaces, energy of cohesion between precursors as well as wettability of surfaces in terms of spreading coefficient are also investigated. Results showed that the Lewis acid-base sub-component of surface energy experiences profound changes, at least 3-fold increase, with temperature, while it is a maximum of 1.5-fold decrease for the Lifshitz-van der Waals sub-component. A cumulative correlation based on the spreading coefficient is also proposed to project the propensity of investigated surfaces to CaSO4 deposition as a function of temperature and is validated using data from the literature.