| abstract |
The invention provides a treatment method of wastewater obtained by washing a crude nitrobenzene product in the process of preparing nitrobenzene through reacting benzene with mixed acid, i.e. a new nitrobenzene washing process and an application of the wastewater generated by washing to the preparation of coal water slurry. The wastewater treated by the method can be used for the preparation of the coal water slurry, so that the recycling rate of water resources is improved. The technical scheme of the invention is that the method comprises the following steps of: mixing an organic phase, i.e. crude nitrobenzene nitrified by the mixed acid with ammonia water with a certain concentration, reacting nitro-phenolic impurities in the crude nitrobenzene with ammonia to generate nitrophenol ammonium and dissolving the nitrophenol ammonium in water. A reacted water phase is separated from the organic phase, the organic phase is washed, and unreacted benzene is distilled out of the organic phase to obtain the nitrobenzene; and the water phase, i.e. nitro phenol ammonium waste liquid is mixed with coal and an additive to prepare the required coal water slurry, and the prepared coal water slurry not only can be used as clean fuel, but also can be used for coal gasification to prepare synthetic gas. |