US EPA

3402018 

Journal Article 

Gas phase hydrolysis of formaldehyde to form methanediol: impact of formic acid catalysis 

Hazra, MK; Francisco, JS; Sinha, A 

2013 

1 

Journal of Physical Chemistry A
ISSN: 1089-5639
EISSN: 1520-5215 

117 

46 

11704-11710 

English 

23614454 

10.1021/jp4008043 

WOS:000327557100012 

We find that formic acid (FA) is very effective at facilitating diol formation through its ability to reduce the barrier for the formaldehyde (HCHO) hydrolysis reaction. The rate limiting step in the mechanism involves the isomerization of a prereactive collision complex formed through either the HCHO···H2O + FA and/or HCHO + FA···H2O pathways. The present study finds that the effective barrier height, defined as the difference between the zero-point vibrational energy (ZPE) corrected energy of the transition state (TS) and the HCHO···H2O + FA and HCHO + FA···H2O starting reagents, are respectively only ∼1 and ∼4 kcal/mol. These barriers are substantially lower than the ∼17 kcal/mol barrier associated with the corresponding step in the hydrolysis of HCHO catalyzed by a single water molecule (HCHO + H2O + H2O). The significantly lower barrier heights for the formic acid catalyzed pathway reveal a new important role that organic acids play in the gas phase hydrolysis of atmospheric carbonyl compounds.