Application of Hydroxylamine Ionic Liquid Salts in Hydroxylation of Benzene to Phenol with Ammonium Molybdate–Copper Chloride–Ionic Liquid System

Several novel hydroxylamine ionic liquid salts were applied in direct hydroxylation of benzene to phenol in ammonium molybdate–copper chloride–ionic liquid system. Hydroxylamine ionic liquid salt was used as the eco-friendly hydroxylation agent, ammonium molybdate and copper chloride were used as the catalyst and additive, respectively, while the ionic liquid was used as the green cosolvent. The new system demonstrated an enhanced phenol selectivity (100%) and phenol yield (11.2%) due to the addition of Cl− and copper ions. Therefore, Cl− ions could increase the phenol selectivity and copper ions helped in improving the phenol yield. Furthermore, the ILs-Mo-Cu catalytic system could be recycled at least three times.