A method of sorbent dialysis is provided for enhanced removal of uremic toxins, such as toxic anions and/or organic solutes, from spent dialysate. More highly adsorbable zirconium polymeric complexes of these anions and/or organic solutes can be initially formed in spent dialysate by treatment with zirconium salt solution or other zirconium cation source, and then removed with adsorbent to provide purified or regenerated dialysate. Sorbent dialysis systems for detoxifying spent dialysate containing toxic anions and organic solutes are also provided.