Mezni cofounded SAH Group in 1994 with Mounir El Jayez. The company was listed on the Tunis Stock Exchange in 2014. The group has a presence in more than 20 countries. In 2017, Mezni and El Jayez also cofounded Azur Detergents, which offers new products, including different types of liquid and powder for washing machines. The group has several subsidiaries under its umbrella, including SAH Algeria, SAH Libya, SAH Morocco, Azur Paper, SAH Ivory Coast, and SAH Senegal. The group reported $200 million in revenues for the first nine months of 2022.