A catalytic reaction unit, comprising: a plurality of catalyst bed layers arranged vertically, each of the catalyst bed layers being filled with a solid catalyst respectively, and an inclined surface on an upper part of the corresponding solid catalyst being arranged between adjacent catalyst bed layers, wherein the inclined surface as a whole is an umbrella-shaped partition, the solid catalyst is supported by a liquid receiving tray, a tail end of the umbrella-shaped partition is provided with an annular downcomer, and the bottom of the annular downcomer is spaced apart from the liquid receiving tray by a certain distance, so that the liquid phase feed enters the catalyst bed layer in a radial direction; a liquid phase feeding subunit, which is arranged above a topmost catalyst bed layer, so that a liquid phase feed can be introduced into the catalyst bed layer, and the liquid phase feed is guided by the inclined surface to sequentially enter each catalyst bed layer from top to bottom; a gas phase feeding subunit, which is arranged between the catalyst bed layer of an upper layer and the inclined surface of the next layer, a gas phase feed of each layer entering the catalyst bed layer in an upward manner; and a gas phase channel, which is relatively isolated from the gas phase feeding subunit, and a gas phase product generated by reaction of the gas phase feed to the liquid phase feed in the catalyst bed layer directly entering the gas phase channel, wherein the gas phase channel is disposed in the middle of the catalytic reaction unit and extends through all the catalyst bed layers from bottom to top, and the catalyst bed layer is provided with: an overflow weir arranged at a side near the gas phase channel; and a liquid-sealing baffle arranged at the upper part of the overflow weir and configured to isolate the gas phase feed from the gas phase product. a plurality of catalyst bed layers arranged vertically, each of the catalyst bed layers being filled with a solid catalyst respectively, and an inclined surface on an upper part of the corresponding solid catalyst being arranged between adjacent catalyst bed layers, wherein the inclined surface as a whole is an umbrella-shaped partition, the solid catalyst is supported by a liquid receiving tray, a tail end of the umbrella-shaped partition is provided with an annular downcomer, and the bottom of the annular downcomer is spaced apart from the liquid receiving tray by a certain distance, so that the liquid phase feed enters the catalyst bed layer in a radial direction; a liquid phase feeding subunit, which is arranged above a topmost catalyst bed layer, so that a liquid phase feed can be introduced into the catalyst bed layer, and the liquid phase feed is guided by the inclined surface to sequentially enter each catalyst bed layer from top to bottom; a gas phase feeding subunit, which is arranged between the catalyst bed layer of an upper layer and the inclined surface of the next layer, a gas phase feed of each layer entering the catalyst bed layer in an upward manner; and a gas phase channel, which is relatively isolated from the gas phase feeding subunit, and a gas phase product generated by reaction of the gas phase feed to the liquid phase feed in the catalyst bed layer directly entering the gas phase channel, wherein the gas phase channel is disposed in the middle of the catalytic reaction unit and extends through all the catalyst bed layers from bottom to top, and the catalyst bed layer is provided with: an overflow weir arranged at a side near the gas phase channel; and a liquid-sealing baffle arranged at the upper part of the overflow weir and configured to isolate the gas phase feed from the gas phase product. an overflow weir arranged at a side near the gas phase channel; and a liquid-sealing baffle arranged at the upper part of the overflow weir and configured to isolate the gas phase feed from the gas phase product.