A First-of-its-Kind Heterogeneous Catalysis Route for Pentaerythritol Synthesis: Toward reduced energy demand and CO2 emissions
Doctoral thesis, 2026
Pentaerythritol (penta) is an important platform chemical traditionally produced from formaldehyde and acetaldehyde using homogeneous alkaline catalysts. The commercial process suffers from extensive downstream separation due to by-product formation, making it energy-intensive and contributing to process-related CO2 emissions. This work explores heterogeneous catalysts as an alternative to conventional liquid alkaline systems for pentaerythritol synthesis.
Catalysts based on alkali and alkaline-earth metals supported on various oxides were evaluated. Among these, Mg-based catalysts supported on γ-Al₂O₃ showed particularly promising performance, combining good activity with improved stability at relatively low metal loadings. Mg-Al hydrotalcites (HTC) emerged as the most stable and selective catalysts, with a selectivity as high as 99.7%. However, post-reaction analyses revealed that formate accumulation on the catalyst surface is a major contributor to deactivation. Additional mechanistic studies provided insight into self-Cannizzaro behaviour and the surface chemistry of formaldehyde on the hydrotalcite materials.
Metal oxide (MOx) catalysts without alkali metals exhibited activity towards penta formation at elevated temperatures. ZnO nanopowder and Zn-supported catalysts were especially selective for penta and its derivatives.
Overall, this thesis highlights the potential and need for further exploration of Mg-based and bifunctional metal-oxides catalyst systems for more sustainable penta synthesis. It also emphasizes the importance of controlling acid-base properties and mitigate formate-induced deactivation to achieve industrial applicability.
Catalysts based on alkali and alkaline-earth metals supported on various oxides were evaluated. Among these, Mg-based catalysts supported on γ-Al₂O₃ showed particularly promising performance, combining good activity with improved stability at relatively low metal loadings. Mg-Al hydrotalcites (HTC) emerged as the most stable and selective catalysts, with a selectivity as high as 99.7%. However, post-reaction analyses revealed that formate accumulation on the catalyst surface is a major contributor to deactivation. Additional mechanistic studies provided insight into self-Cannizzaro behaviour and the surface chemistry of formaldehyde on the hydrotalcite materials.
Metal oxide (MOx) catalysts without alkali metals exhibited activity towards penta formation at elevated temperatures. ZnO nanopowder and Zn-supported catalysts were especially selective for penta and its derivatives.
Overall, this thesis highlights the potential and need for further exploration of Mg-based and bifunctional metal-oxides catalyst systems for more sustainable penta synthesis. It also emphasizes the importance of controlling acid-base properties and mitigate formate-induced deactivation to achieve industrial applicability.
Pentaerythritol
acetaldehyde
formaldehyde
hydrotalcites
solid alkaline catalyst
Cannizzaro reactions
aldol condensation
ZnO
10:an hall, Kemigården 4, Chalmers University of Technology, Göteborg, Sweden
Opponent: Professor Karen Wilson, Griffith University, Australia
Author
Aqsa Noreen
Chalmers, Chemistry and Chemical Engineering, Chemical Technology
Let’s achieve it with catalysis!
In 2025, the need for decisive global action on climate change is more urgent than ever. In response, the European Union has set an ambitious target, achieving net-zero greenhouse gas emissions by 2050. Among the many strategies required to reach this goal, making existing manufacturing processes more energy-efficient and less carbon-intensive is essential.
This thesis explores one such opportunity by investigating whether a long-established industrial process, the production of pentaerythritol (Penta), can be made more sustainable. Penta is an important platform chemical used to produce coatings, lubricants, resins, and many other everyday products. Traditionally, it is manufactured using homogeneous (liquid-based) catalysts. While effective, producing high-purity penta on an industrial scale is inherently complex and energy-intensive, largely due to the extensive separation required.
Here, the potential of replacing these conventional homogeneous catalysts with solid (heterogeneous) catalysts was explored. Because the catalyst is in solid form, the separation process can be simplified and made less energy-intensive. Several types of solid catalysts were designed, synthesized, and examined to understand which properties most strongly influence the selective formation of Penta. The effective catalyst requires a precise balance of acidic and basic sites, appropriate composition, and high stability, to enable high-yield Penta production.
By demonstrating how heterogeneous catalysis can be introduced into Pentaerythritol synthesis, this thesis contributes to bridging the gap between traditional industrial practices and the development of more sustainable catalytic processes. In doing so, it offers a promising pathway toward reducing CO₂ emissions and supports broader efforts to meet future climate targets.
In 2025, the need for decisive global action on climate change is more urgent than ever. In response, the European Union has set an ambitious target, achieving net-zero greenhouse gas emissions by 2050. Among the many strategies required to reach this goal, making existing manufacturing processes more energy-efficient and less carbon-intensive is essential.
This thesis explores one such opportunity by investigating whether a long-established industrial process, the production of pentaerythritol (Penta), can be made more sustainable. Penta is an important platform chemical used to produce coatings, lubricants, resins, and many other everyday products. Traditionally, it is manufactured using homogeneous (liquid-based) catalysts. While effective, producing high-purity penta on an industrial scale is inherently complex and energy-intensive, largely due to the extensive separation required.
Here, the potential of replacing these conventional homogeneous catalysts with solid (heterogeneous) catalysts was explored. Because the catalyst is in solid form, the separation process can be simplified and made less energy-intensive. Several types of solid catalysts were designed, synthesized, and examined to understand which properties most strongly influence the selective formation of Penta. The effective catalyst requires a precise balance of acidic and basic sites, appropriate composition, and high stability, to enable high-yield Penta production.
By demonstrating how heterogeneous catalysis can be introduced into Pentaerythritol synthesis, this thesis contributes to bridging the gap between traditional industrial practices and the development of more sustainable catalytic processes. In doing so, it offers a promising pathway toward reducing CO₂ emissions and supports broader efforts to meet future climate targets.
Driving Forces
Sustainable development
Subject Categories (SSIF 2025)
Chemical Engineering
DOI
10.63959/chalmers.dt/5836
ISBN
978-91-8103-379-3
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5836
Publisher
Chalmers
10:an hall, Kemigården 4, Chalmers University of Technology, Göteborg, Sweden
Opponent: Professor Karen Wilson, Griffith University, Australia