A third possibility is to further crystallize the mother liquor yielding a more impure APT. Also, treatment of mother liquor with hexamethylene tetramine to precipitate tungsten was proposed.
Ang isang ikatlong posibilidad ay upang higit pang gawing kristal ang ina gawing alak walang tutol sa isang mas marumi apt. Gayundin, paggamot ng ina gawing alak na may hexamethylene tetramine sa namuo Tungsten ay iminungkahi.