Ultrafiltration small-scale test device

The utility model discloses an ultrafiltration small-scale test device, and belongs to the technical field of biology. The device comprises an ultrafiltration tank, an ultrafiltration machine and a pipe joint, the pipe joint is connected with the bottom of the ultrafiltration tank through a pipeline A, a valve A is arranged at the end, close to the ultrafiltration tank, of the pipeline A, the pipe joint is connected with a liquid inlet of the ultrafiltration machine through a pipeline B, a buffer solution pipe is connected to the pipe joint, and a valve B is arranged at the end, close to the ultrafiltration tank, of the pipe joint. A valve C is arranged at one end, close to the pipe joint, of the buffer solution pipe. In the whole ultrafiltration and replacement process of the feed liquid, only the valve needs to be controlled, the pipeline does not need to be disassembled and assembled, the feed liquid is not lost, the yield of the ultrafiltration step is improved, the feed liquid does not make contact with