**About the Editor**

**Dariush Azizi** is a metallurgist working in the department of extractive metallurgy at SGS Natural Resources, Lakefield, Canada. He received his PhD in chemical engineering from Laval University, Quebec, Canada, in 2018. His research areas mostly focus on the integration of the concepts of sustainability in mining and the metal sector, specifically, in mineral processing and extractive metallurgy process development to produce critical metals from secondary and primary resources. Since 2013, he has worked in different research institutes and private companies in Canada, and during this period, he has been involved in a variety of R&D and industrial projects with outstanding outputs.
