The green synthesis of heterogeneous catalysts often requires a solid-state reaction pathway. In this work, a cationic surfactant (CTAB) embedded sulfonated carbon catalyst was prepared via a sustainable route with the aim of having controlled surface hydrophobicity and acidity for glycerol acetalization reactions. The main objective of this study was to tune the hydrophobicity and acidic site density, either via adding a cationic surfactant or changing the carbon to sulphur ratio. The as-synthesized catalyst was characterized via XRD, N₂ adsorption/desorption, SAXS, FESEM, FTIR, pyridine-IR, high-temperature DR-FTIR, TGA, ¹³C-NMR, Raman, and XPS techniques. The incorporation of a cationic surfactant (CTAB) reduces the surface area but increases the acidic site density to a greater extent. The bonding between the surfactant (CTAB) and surface hydroxyl groups was elucidated via XPS analysis. DR-FTIR studies implied that the –SO₃H groups are strongly bonded to the carbon network, while the lower amount of water mass loss seen from TGA studies showed the substantial improvement in surface hydrophobicity after modification with the surfactant. Moreover, the combination of acidic site density and hydrophobicity played a key role in attaining around 90% glycerol conversion and 98% solketal selectivity under ambient conditions. Notably, characterization of the used catalyst revealed that the loss of activity is mainly related to a drop in hydrophobicity, which occurs due to the loss of surfactant during washing with methanol.

Catalytic dehydration of isopropanol to propylene is a common reaction in laboratories to characterize the acid–base properties of catalysts. When acetone is produced, it is the sign of the presence of basic active sites, while propylene is produced on the acid sites. About 2/3rd of the world production of isopropanol is made from propylene, and the other third is made from acetone hydrogenation. Since the surplus acetone available on the market is mainly a coproduct of phenol synthesis, variations in the demand for phenol affect the supply position of acetone and vice versa. High propylene price and low demand for acetone should revive the industrial interest in acetone conversion. In addition, there is an increasing interest in the production of acetone and isopropanol from CO/CO₂ via expected more environmentally friendly biochemical conversion routes. To preserve phenol process economics, surplus acetone should be recycled to propylene via the acetone hydrogenation and isopropanol dehydration routes. Some critical impurities present in petrochemical propylene are avoided in the recycling process. In this review, the selection criteria for the isopropanol dehydration catalysts at commercial scale are derived from the patent literature and analyzed with academic literature. The choice of the process conditions, such as pressure, temperature and gas velocity, and the catalysts’ properties such as pore size and acid–base behavior, are critical factors influencing the purity of propylene. Dehydration of isopropanol under pressure facilitates the downstream separation of products and the isolation of propylene to yield a high-purity “polymer grade”. However, it requires to operate at a higher temperature, which is a challenge for the catalyst’s lifetime; whereas operation at near atmospheric pressure, and eventually in a diluted stream, is relevant for applications that would tolerate a lower propylene purity (chemical grade).

Fatty nitriles have lately become of interest in the framework of biofuels and for the valorization of the oil part of biomass to form fine chemicals or polymers. The production of long‐chain fatty nitriles by the direct reaction of acids with NH₃ has not been extensively studied, although several catalysts have been developed and published as patents. The characterization of this reaction with and without catalyst is, to the best of our knowledge, performed for the first time in this study. Several catalysts with various acid–base features were tested, and the best catalysts at 250 °C (Zn‐ and In‐based catalysts) were further studied. Catalytically active forms and models are proposed for the Zn‐ and In‐based catalysts, and the kinetic parameters for the amide to nitrile reaction are evaluated.