“…There are important flotation applications in different countries around the world such as the United States, Australia, China, India, Germany, and Russia (Bentli, 2000). Various studies have been conducted on the coal production process with low ash and sulphur (Atak and Onal, 1991;Ozbayoğlu and Bilgen, 1997;Steel and Patrick, 2001;Karaca and Onal, 2003;Sonmez et al, 2005;Dash et al, 2007). In these studies, the efficiency of acid/base leaching methods was investigated besides flotation to reduce the ash and sulphur content of coal, and significant results were obtained from these studies.…”