عنوان مقاله [English]
In this research, manganese hydrogen sulfate as a novel green catalyst was used to synthetize diazo dyes. Manganese hydrogen sulfate was used as a hydrogen source to produce diazonium salt and then, the obtained anion formed a stable gel with diazonium salt at room temperature which was stable until 70 °C. Moreover, in order to produce diazonium salts, synthetic heterocyclic amines were utilized. The proposed heterogeneous acidic catalyst, manganese hydrogen sulfate, can be applied in industrial scale due to the advantages such as environmentally friendly features and easy catalyst transfer. This method provides several advantages such as, high-efficiency catalyst, mild operational conditions, room temperature conditions, low cost, availability, easy catalyst preparation, and a simple workup procedure.