The current chemical industry primarily relies on basic
molecules
from petroleum. Nevertheless, these molecules, known as building block
chemicals, can be synthesized from biomass. Therefore, the aim of
this work was to evaluate the production of formic acid (FA) and levulinic
acid (LA) from agro-industrial waste, particularly potato peel (PP),
using a microwave-assisted hydrothermal treatment. The sample was
conditioned and characterized by a physicochemical analysis. The results
indicated that the PP had a high moisture content (≈ 82%) and
a total carbohydrate content of 39.8%. Subsequently, a 23 factorial design was established to study the effect of temperature
(100 to 180 °C), H2SO4 concentration (0
to 0.6 M) and reaction time (5 to 30 min.) on FA and LA conversion.
From the experimental trials, it was possible to establish that the
highest FA (2.51%) and LA (13.77%) yields were obtained at 180 °C
and 0.6 M H2SO4. When ANOVA analysis was performed,
it was observed that the temperature and H2SO4 concentration were the most influential parameters on FA and LA
conversion. Finally, to improve the process, some tests were performed
with a new set of temperatures (160, 180, and 200 °C) and acid
concentrations (0.3, 0.6, and 1.0 M), and a previous hydrolysis stage
was established, where the highest FA (3.19%) and LA (27.95%) yields
were found at 160 °C and 1.0 M H2SO4. This
work showed that it is possible to obtain value-added products from
agro-industrial waste such as PP; however, further studies and experiments
focused on improving the yield of the process are still required.