This disclosure generally relates to at least one reusable module of a sorbent cartridge in a sorbent dialysis system. Given the cost of sorbent cartridges and sorbent materials, it would be advantageous if parts of the cartridge could be reused or recharged. In one aspect of the invention, the sorbent cartridge has parallel modules for in-line recharging of sorbent materials using alternate duty cycles. The sorbent cartridge can have two or more modules positioned parallel to one another, and the modules are fluidly connected to one another through connectors. The modules can be reusable and the sorbent materials contained in the modules can be recharged.
