Clean production method and device of dinitrotoluene

The invention relates to a clean production method and a clean production device of dinitrotoluene, belonging to the field of chemical processes. The clean production method for preparing dinitrotoluene is realized through a methylbenzene micro-reactor nitration process, a fiber bed liquid-liquid separator separation process of nitric acid and dinitrotoluene mixture, and a dilute nitric acid thickening and concentration process. The clean production device of dinitrotoluene comprises a micro-reactor, a fiber bed separator, a mixing tank, a high-pressure kettle, a cooler, a bleaching tower, a concentrating tower, a condenser, a nitric acid storage tank, a delivery pump, a magnesium sulfate storage tank and an evaporator. Since nitration reaction is completed by using the micro-reactor, the micro-reactor consists of many micro-tubes which are connected in parallel, the specific surface area is very large and continuous production processes are formed, the heat exchange efficiency and the mixing efficiency are good, the reaction temperature can be accurately controlled, reaction materials can be accurately controlled to be instantly mixed according to accurate proportions, the yield, the selectivity and the safety are improved, and the reaction time is reduced.