D 1707 (OTTO) Diethylenetriaminepentaacetic acid, GR 99%+ Cas 67-43-6 - used for sequestering metal ions that otherwise decompose hydrogen peroxide, which is used to bleach pulp in paper making. D 1707 (OTTO) Diethylenetriaminepentaacetic acid, GR 99%+ Cas 67-43-6 - used in soaps as a water softener.