End-stage renal disease is a global health problem and a wearable artificial kidney (WAK) can effectively reduce the restrictive time required for dialysis treatment. The dialysate purification system is a key module in the WAK, which removes various nanotoxins from used dialysate. In this paper, activated carbon was used to remove creatinine, a nanotoxin, and the differences in adsorption performance of different types of activated carbon and their influencing factors were discussed in detail through a series of experiments, and finally the best adsorption performance of activated carbon microspheres was concluded. This is a great help for the subsequent design of the purification system.