The semiconductor industry stripper solution contains N-methylformamide (NMF), which hydrolyzes to methylamine during distillation recovery, reducing NMF recovery and causing secondary pollution. This study investigated the effects of various conditions on NMF hydrolysis and its kinetics. The recovery process was optimized by adding a roots pump and forced circulation at the evaporator bottom. In engineering application, the operating pressure was reduced by 2.67–6.67 kPa, temperature by 10–30 °C, with fluctuations narrowed from <10 °C to <5 °C and from <1.33 kPa to <0.67 kPa, enhancing system stability and significantly reducing NMF hydrolysis. Based on 2 × 10 6 Mg·a -1 waste stripper solution, the optimized process reduced NMF loss from 5760 Mg·a -1 to 1620 Mg·a -1 , and methylamine waste from 3026 Mg·a -1 to 851.2 Mg·a -1 . This optimized process improves organic solvent recovery efficiency and reduces methylamine wastewater discharge, offering a feasible solution for water pollution control in the TFT-LCD industry.
Ni et al. (Fri,) studied this question.