Effect of Metal Chloride and Complex Salt Modification on the Pyrolysis, Kinetics, and Burnout Behavior of High-Ash Indian Coal

The present study reveals the effect of metal chlorides and altering complex salts on pyrolysis, kinetic, and burnout characteristics of high-ash Indian coal. It was also observed in the study that 6% sodium hexanitritocobaltate has the lowest maximum Ti 378°C instead of 394°C and Tp 491°C instead of 512°C and lowest ultimate burnout temperature (Tf) of 707°C compared to both raw coal and other treatments. The Coats–Redfern method for studying suggests that most significant reduction in E occurs when coal is treated with 3% stannous chloride, resulting in a drop from 42.92 kJ/mol (Raw Coal) to 18.51 kJ/mol. It might be due to the formation of active sites on the surface of coal. Zinc Chloride facilitates substantial porosity and stannous chloride provides regulated breakdown with modest porosity and structural stability. However, sodium hexanitritocobaltate persuade rapid thermal breakdown with variety of surface shapes. The study also illustrates that at 30-minute time, the char reactivity was significantly high at pyrolysis temperature of 610°C. It was observed in the study that as we increase the chemical concentration of stannous chloride, there is a notable increase in burnout, as high as 9%. Zinc chloride and stannous chloride, influenced by temperature more rapidly as compared to sodium hexanitritocobaltate encourage cracking, dehydration processes and altering the composition of gas and tar products. This benefit is evidenced by the increased burnout observed at 610°C and 710°C for the stannous chloride-impregnated coal.