Malonic acid (MA) is a high-value dicarboxylic acid with strong industrial demand, yet its current production heavily relies on petrochemical feedstocks. Here, we report the first systematic study for the sustainable production of MA via oxidation of 3-hydroxypropionic acid (3-HP) with a Pd/Carbon catalyst. The effects of oxidant type (O₂ and H₂O₂), pH, and temperature on the reaction chemistry were comprehensively evaluated. Guided by experimental observation and DFT-calculated thermochemical energetics, reaction networks for 3-HP oxidation with both oxidants are proposed and validated through kinetic modeling. MA was identified as the primary oxidation product, while further oxidation yields acetic acid and oxalic acid. The kinetic model validated the network, displaying excellent agreement (R² > 0.95). Kinetic observations also enabled a direct comparison between O₂ and H₂O₂ and revealed their distinct behaviors. The model was further developed into a temperature-time map, providing insight into conditions that maximize MA production. Malonic acid selectivity of 56.9 % and yield of 50.5 % were achieved at 3 bar oxygen, equimolar NaOH:3-HP ratio, and 50 °C.

Authors

Seonyeong Kim, Javier Chavarrio, Joseph Install, George Huber(Corresponding)
University of Wisconsin-Madison DOE Center for Advanced Bioenergy and Bioproducts Innovation

seonyeong.kim@wisc.edu
gwhuber@wisc.edu

Nov 2025

Description

This repository contains the experimental data and processed results supporting the publication:
Selective Oxidation of 3-Hydroxypropionic Acid to Malonic Acid over Pd/C: Mechanistic and Kinetic Study

The dataset includes raw data and analysis scripts used to generate the figures and tables reported in the manuscript.
Figures were generated using Adobe illustrator 2025, Origin 2025, and MATLAB R2024a.

File Contents

Filename	Description
README.md	This metadata file
APCATB-D-25-08770_dataset.xlsx	Raw data and figures for the 3-HP oxidation experiments
APCATB_D_25_08770_kinetic_opt.m	MATLAB code for general kineitc parameters optimization
APCATB_D_25_08770_heatmap.m	MATLAB code for generating heatmaps
1-1_O2_initial_run.csv	Raw .csv data of O2 initial run
1-2_H2O2_initial_run.csv	Raw .csv data of H2O2 initial run
2-1_H2O2_experiments.csv	Raw .csv data of H2O2 experiments
2-2_H2O2_experiments.csv	Raw .csv data of H2O2 experiments
2-3_H2O2_experiments.csv	Raw .csv data of H2O2 experiments
3-1_O2_experiments.csv	Raw .csv data of O2 experiments
3-2_O2_experiments.csv	Raw .csv data of O2 experiments
3-3_O2_experiments.csv	Raw .csv data of O2 experiments
4-1_MA_degradation.csv	Raw .csv data of MA degradation experimients
4-2_MA_degradation.csv	Raw .csv data of MA degradation experimients
5_XRD.csv	Raw .csv data of XRD spectra of catalysts
6_XPS.csv	Raw .csv data of XPS spectra of catalysts
7_reusability.csv	Raw .csv data of reusability experiments
8_thermodynamic_network.csv	Raw .csv data of thermodynamic networks
9_thermodynamics.csv	Raw .csv data of thermodynamics over temperature range
10-1_kinetic_model_H2O2.csv	Raw .csv data of H2O2 kinetic model at 50 C
10-2_kinetic_model_O2.csv	Raw .csv data of O2 kinetic model at 50 C
11-1_25C_Kinetic.csv	Raw .csv data of O2 kinetic model at 25 C
11-2_75C_Kinetic.csv	Raw .csv data of O2 kinetic model at 75 C
11-3_100C_Kinetic.csv	Raw .csv data of O2 kinetic model at 100 C
11-4_Arrhenius.csv	Raw .csv data of Arrhenius plot of O2 kinetic models

APCATB-D-25-08770_dataset.xlsx (and separate .csv files)

O2 H2O2 initial run (1-1, 1-2)
- Changing molar concentrations of each species through 3-HP oxidation experiment: 60 mM feed, 0.2 g catalyst, NaOH 1 eq., at 50 ◦C, with (a) O2 3 bar and (b) H2O2 15 eq. as oxidants
H2O2 experiments (2-1, 2-2, 2-3)
- Oxidation of 3-HP with H2O2, as a function of (a) ratio of H2O2/3-HP, (b) NaOH/3-HP and (c) temperature with a fixed amount of oxidant amount (3-HP: H2O2 = 1:15).
- All reactions were carried out with 60 mM 3-HP, 0.2 g Pd/C catalyst, NaOH/3-HP = 1:1, and 50◦C for 8 h unless otherwise noted.
O2 experiments (3-1, 3-2, 3-3)
- Oxidation of 3-HP, as a function of (a) O2 pressure, (b) NaOH/3-HP ratio, and (c) temperature with a fixed amount of oxidant (O2 3 bar).
- Reactions were carried out with 60 mM 3-HP, 0.2 g Pd/C catalyst, NaOH/3-HP = 1:1, 8 h, under 50 ◦C.
MA degradation (4-1, 4-2)
- Oxidation of MA under O2; (a) effect of temperatures and (b) concentration of MA as a function of time at 50 ◦C (open circles) and 100 ◦C (solid circles).
- All experiments were conducted under 3 bar of O2, 60 mM MA, NaOH 1 eq., 0.2 g catalyst for 1300 min.
XRD
- X-ray diffractogram (θ–2θ) of unreduced, fresh, and spent catalyst.
XPS
- XPS profiles of (a) Pd 3d for fresh and spent Pd/C catalyst.
reusability
- Three cycles of catalyst reusability test. Experimental conditions were maintained as: NaOH 1 eq., O2 3 bar, 50 ◦C, and 8 h .
Thermodynamic network
- ΔGrxn values of the proposed 3-HP oxidation network.
- All energies are calculated in aqueous phase at reaction temperature (50 ◦C) at M06–2X/aug-cc-pVTZ level of theory.
Thermodynamic
- (a) ΔGrxn and (b) ΔHrxn of 3-HP oxidation (solid) and MA degradation (empty).
- Each temperature point were evaluated at M06–2X/aug-cc-pVTZ level in aqueous phase.
Kinetic model (10-1, 10-2)
- Experimental (circle) and modeled (solid line) concentration profiles for 3-HP oxidation using (a) H2O2 and (b) O2 as oxidants.
- Both experiments were performed at 3-HP 60 mM, 0.2 g Pd/C, NaOH/3-HP = 1:1, 50 ◦C and 3 bar of (a) Ar / (b) O2. 15 H2O2 was used for (a).
Arrhenius plot (11-1, 11-2, 11-3, 11-4)
- Comparison of modeled data and experimental results under (a) 25 ◦C, (b) 75 ◦C, and (c) 100 ◦C.
- Arrhenius plot for three reactions. Reaction conditions: 3-HP 60 mM, 0.2 g Pd/C, NaOH/3-HP = 1:1, and 3 bar of O2.

APCATB_D_25_08770_kinetic_opt.m

- MATLAB code for general kineitc parameters optimization, used for 9. Kinetic model in xlsx dataset.

APCATB_D_25_08770_heatmap.m

- MATLAB code for generating heatmaps, expanded from 10. Arrhenius plot data.

Software and Dependencies

MATLAB R2024a
Optimization Toolbox
Statistics and Machine Learning Toolbox

Notes

MATLAB codes included here is an example. Details were adjusted for each time (H2O2, O2, parameters to fit, etc).

Acknowledgements

This work was funded by the DOE Center for Advanced Bioenergy and Bioproducts Innovation
(U.S. Department of Energy, Office of Science, Biological and Environmental Research Program
under Award Number DE-SC0018420). Any opinions, findings, and conclusions or
recommendations expressed in this publication are those of the author(s) and do not necessarily
reflect the views of the U.S. Department of Energy. Authors are grateful to Timo Repo for great
discussions and Manos Mavrikakis for providing computational resources and invaluable guidance.

Data and code from: Selective oxidation of 3-hydroxypropionic acid to malonic acid over Pd/C: Mechanistic and kinetic study

Data files

Abstract

Authors

Description

File Contents

Software and Dependencies

Notes

Acknowledgements

Data and code from: Selective oxidation of 3-hydroxypropionic acid to malonic acid over Pd/C: Mechanistic and kinetic study

Data files

Abstract

README: Data and code from: Selective oxidation of 3-hydroxypropionic acid to malonic acid over Pd/C: Mechanistic and kinetic study

Authors

Description

File Contents

Software and Dependencies

Notes

Acknowledgements