Cellulose triacetate manufacturing uses Dicloromethane and Methanol:
| Process solvent | Foundational | Progressive | Aspirational |
|---|---|---|---|
|
Dichloromethane (DCM) |
98.0% | 98.5% | 99.0% |
| Methanol | 98.5% | 99.0% | 99.5% |
The recovery performance of DCM and methanol should be reported and assessed separately against the corresponding thresholds shown above. For cellulose triacetate, these requirements apply instead of the acetone-based recovery references used for cellulose diacetate.
Important: This clarification covers solvent recovery requirements only. DCM- and methanol-specific air-emission requirements require further technical discussion and may be incorporated into a future revision of the ZDHC MMCF Guidelines. All other applicable ZDHC MMCF requirements remain unchanged.