The utility model discloses a sampling device for a heterogeneous reaction kettle. The sampling device comprises a sampling sleeve and a sampling lifter which are fixed on the inner wall of the reaction kettle, the lower end of the sampling sleeve is inserted into reaction liquid in the reaction kettle, the upper end of the sampling sleeve is fixed on the reaction kettle through a
flange, and the sampling sleeve is positioned between the stirring
paddle and the inner wall of the reaction kettle; the
flange is connected with a T-shaped three-way
pipe, a main
pipe of the T-shaped three-way
pipe and the sampling sleeve are coaxially arranged, one side, far away from the sampling sleeve, of the main pipe of the T-shaped three-way pipe is connected with a first valve, and one side, far away from the T-shaped three-way pipe, of the first valve is connected with a funnel; a
branch pipe of the T-shaped three-way pipe is connected with a second valve, and the second valve is used for being connected with an external
nitrogen source; the sampling lifter sequentially penetrates through the funnel, the opened first valve, the main pipe of the T-shaped three-way pipe, the
flange and the sampling sleeve through the
rope for sampling. According to the utility model, the sampling lifter and the
rope are isolated from the stirring
paddle through the sampling sleeve, so that the
rope is prevented from being wound on the stirring
paddle, and the stirring paddle does not need to be stopped during sampling. In addition, the sampling lifter is used for sampling from the sampling sleeve, so that the problem of blockage of the sampling sleeve can be effectively avoided.