Xanthates is a family of highly efficient collectors, widely used in the industry of sulphide minerals flotation, which, however is considered toxic and hazardous to the environment, and can pose significant risks to aquatic life and human health. The need for its replacement by other more environmental friendly reagents is of vital importance towards a more sustainable extractive industry.

Organosolv lignin  is natural, biodegradable material that possesses a low carbon footprint compared to the conventional reagents. The study investigates the potentiality of the use of organosolv lignin as collector in the flotation of metalic sulphide minerals (sphalerite, pyrite/arsenopyrite) from greek mixed sulphides. Critical parameters under investigation was the collector dosage and composition, while the efficiency of the collector formula was evaluated according to the achieved selectivity, grade and recovery. To simulate and evaluate the performance of the optimum formula under realistic operating conditions, locked cycle flotation tests were carried out and the results are discussed.