Study of catalytic action of micro-particles and synthesized nanoparticles of CuS on cellulose pyrolysis

The catalytic action of copper sulfide (CuS) micro-particles and as-synthesized nanoparticles was studied on cellulose pyrolysis. The market procured CuS powder was used as micro-particles without any treatment. The CuS nanoparticles were synthesized at ambient temperature by simple wet chemical technique. Before using the micro-particles and nanoparticles for catalytic study, they were comprehensively characterized. The thermal analysis including catalytic properties of both the micro-particles and nanoparticles of CuS on cellulose pyrolysis was studied employing thermogravimetric (TG), differential thermogravimetric, and differential thermal analysis techniques. Prior to the study as catalyst in cellulose pyrolysis, the CuS micro- and nanoparticles were characterized by thermal analysis in inert atmosphere. The TG curves showed two steps and five steps decomposition having total mass loss of 29 and 42 % in case of CuS micro- and as-synthesized nanoparticles, respectively. The catalytic study in cellulose pyrolysis showed that the decomposition commences at temperature 295 °C for pure cellulose, 270 °C for cellulose mixed with 3 % CuS micro-particles and 205 °C for cellulose mixed with 3 % CuS nanoparticles. It clearly showed that the decomposition starting temperature decreased by 65 °C in case of cellulose mixed with CuS nanoparticles compared to cellulose mixed with CuS micro-particles. Thus, CuS nanoparticles act as better catalyst then CuS micro-particles in cellulose pyrolysis. The obtained results are deliberated in details.