cs7b03558_si_001.pdf (1.23 MB)
Highly Efficient Oxidation of Ethyl Lactate to Ethyl Pyruvate Catalyzed by TS‑1 Under Mild Conditions
journal contribution
posted on 2018-01-04, 00:00 authored by Tianliang Lu, Junpeng Zou, Yuzhong Zhan, Xiaomei Yang, Yiqiang Wen, Xiangyu Wang, Lipeng Zhou, Jie XuHighly
efficient oxidation of ethyl lactate (ELA) to ethyl pyruvate
(EP) was realized over TS-1 in the presence of aqueous H2O2 (30 wt %) at low temperature without other solvent.
A 100% ELA conversion and 97.8% EP yield were obtained at 50 °C
after 9 h. The conversion rate of ELA is sensitive to the reaction
temperature. High reaction temperature (70 °C) leads to an increase
in conversion rate of ELA but causes the fast hydrolysis and decarboxylation
of EP to form byproducts of acetic acid and CO2. On the
basis of the characterization (pyridine-FTIR and UV–vis) and
reaction results, active species of Ti(OOH) were proven. In addition,
a nonradical mechanism for conversion of ELA to EP for this catalytic
system was proposed. By kinetic analysis, the formation of Ti(OOH)
is confirmed as the rate-determining step. The apparent activation
energy (103.4 kJ mol–1) was also obtained. Furthermore,
TS-1 was highly stable for the oxidation of ethyl lactate. There were
almost no change in ELA conversion and EP yield throughout 10 reaction
runs.