Study of the Reaction Mechanisms during the Thermal Decomposition of Arsenic Sulfide (V) at High Temperatures under Non-Isothermal Conditions

The reaction mechanisms during thermal decomposition in As-S systems are complex to describe due to the physicochemical characteristics of arsenic and its sulfides. Non-isothermal tests were carried out in a NETZSCH DTA/TG thermal analysis equipment, and interrupted tests were carried out in a vertical oven adapted for this purpose; both tests were carried out in an inert nitrogen atmosphere. The information obtained experimentally was analyzed and correlated to determine the phases and reaction mechanisms during the thermal decomposition of an arsenic sulfide (V) sample. As a result of this study, the mechanism of thermal decomposition of an arsenic sulfide sample was obtained and the apparent activation energy was determined by the Kissinger and Ozawa methods.