Non-immobilized water -insoluble metallosalens as efficient heterogeneous catalyst for degradation of dyes in water

The heterogenization of homogeneous catalysts is among the main strategies employed to overcome the problems associated with the oxidative degradation of metalloporphyrins and metallosalens. Also, the catalyst may be easily separated from the reaction mixture and reused in the case of heterogeneous catalysts. However, relatively elaborate synthetic and purification procedures are required to immobilize homogeneous catalysts on solid supports. An innovative strategy is the use of non-immobilized water-insoluble coordination complexes in water. The hydrophobic/hydrophilic force drives the reaction under heterogeneous conditions. [1-3]Industrial dye wastewater from textile and photographic industry is a principal source of environmental contamination. Large amounts of dye were released into the environment accompanied by dissolved inorganic salts, surfactants, dispersing agents, and other organics. Due to the increasing environmental pollution and the establishment of stringent standards for rejecting wastewaters, developed techniques are urgently needed to purify the industrial wastewater.[4]In this study, water-insoluble metallosalen complexes were synthesized and initially applied to activate different oxidants toward degradation of various industrial dyes. The different parameters affecting oxidative activity of hydrophobic catalysts were investigated under heterogeneous conditions.