Refining process of o-nitrophenol

The invention belongs to the technical field of chemical engineering and particularly relates to a refining process of o-nitrophenol. According to the refining process of the o-nitrophenol, 100kg of o-nitroanisole is excessively recovered from per 10 tons of waste water, and the production cost of the o-nitroanisole is reduced. Active carbon is added for absorption, the purity of the o-nitrophenol is improved, and the original content lower than 95 percent is improved to the content higher than 99 percent. The activated carbon regeneration is carried out, the o-nitroanisole is further extracted, activated carbon can be cyclically utilized, and meanwhile, the recovery rate of the o-nitroanisole is improved. In the original process, the purification can be carried out only through the rectification. According to the refining process provided by the invention, the purity of the o-nitrophenol can be improved through distillation, and energy sources and equipment are saved. The waste water chemical oxygen demand (COD) is reduced by a half through being compared with the results of the original process, impurities are absorbed by the active carbon, the content of the impurities is greatly reduced, and the waste water treatment by resin absorption is favorably realized.