Device and method for shortening ketalation time in ibuprofen synthesis process

The invention relates to a device for shortening ketalation time in an ibuprofen synthesis process through reactive rectification, and a method for shortening ketalation time in an ibuprofen production process. The device consists of a reaction kettle (R), a rectification tower (T), a reboiler (E1), a condenser (E2), a reflux tank (A) and a circulating pump (P). The method comprises the following steps: adding a certain amount of chlorone-containing petroleum ether solution, neopentyl glycol and dilute sulfuric acid into the reaction kettle (R); heating the liquor in the reaction kettle (R) by use of steam in a jacket; introducing gas phase of the heated liquor into the rectification tower (T) to separate; feeding tank liquor of the reaction kettle (R) into the reboiler (E1) through the circulating pump (P) to heat; feeding into the reaction kettle (R); condensing the steam withdrawn on the tower top into condensation water through the condenser (E2) to obtain petroleum ether and water; layering the solution in the reflux tank (A), taking the upper layer of petroleum ether as overhead reflux, and withdrawing and recovering the lower layer of water.