4,4-dimethyl-1,3-dioxane synthesis method

The invention relates to a 4,4-dimethyl-1,3-dioxane synthesis method. According to the 4,4-dimethyl-1,3-dioxane synthesis method, reaction monomers enter into a reactor respectively from different inlets, wherein an organic phase isobutene or isobutene-containing C4 fraction enters into the reactor from the lower part of the reactor and flows upward and a water phase phosphoric acid solution enters into the reactor from the upper part of the reactor and flows downward, the water phase material and the oil phase material contact in a counter current contact way in a multistage filling material zone and are fully dispersed so that a reaction is promoted, the reacted water phase is discharged from the bottom and the oil phase is discharged from the upper part. The 4,4-dimethyl-1,3-dioxane synthesis method has the advantages that a reaction conversion rate is high, reaction is thorough, formaldehyde-caused side reaction in the downstream process is greatly reduced, the reaction can be controlled easily, according to yield requirements, technical process conditions can be adjusted in the same reactor by adjustment of tertiary butanol and formaldehyde inlets so that the optimal reaction effects are obtained, and when the reaction occurs fluctuation, the reaction case can be improved and controlled by adjustment of the tertiary butanol and formaldehyde inlet positions.