Catalytic performance and deactivation mechanism of a one-step sulfonated carbon-based solid-acid catalyst in an esterification reaction

State‐of‐the‐Art of the Synthesis and Applications of Sulfonated Carbon‐Based Catalysts for Biodiesel Production: a Review

“…[ 109 ] Some of the sulfonated catalysts show absorption bands at 1592 and 1704 cm −1 due to the existence of polycyclic aromatic hydrocarbons and COOH groups, which are ascribed to the stretching mode of CC and C═O, respectively. [ 37 ] These findings can deduce that the organic composition of the carbon precursors has been carbonized to form aromatic polycyclic hydrocarbons and SO 3 H groups are introduced during sulfonation stage. The absence of the COC stretching in the sulfonated catalysts can be explained by the happening of dehydration in the raw material during the carbonation phase, in which the molecular structure of hemicellulose, cellulose, and lignin and eventually breaks the bonding.…”

“…The nonsulfonated BC derived from EFB exhibited S BET of 5.677 m 2 g À1 and was declined to 2.851 m 2 g À1 after sulfonated by 4-BDS. [36a] In another study, the S BET of the bamboo BC reduced from 4.26 to 2.60 m 2 g À1 after sulfonated by H 2 SO 4 for 4 h at 150 C. [37] As observed in the SCC, this decreasing trend can be explained by the incidence of pores collapse due to the incomplete carbonization, oxidation, and polymerization of the macromolecular substances in the carbon precursors. The porosity of the catalyst is also reduced by covering parts of the pore space of the ─SO 3 H groups on the carbon surface.…”

“…In addition, the use of biomass‐derived catalysts instead of conventional transition metal‐based catalysts may also contribute to the high waste recovery while simultaneously reducing the waste disposal issues of the agricultural sector. Today, the SBC and SAC catalysts used for biodiesel production are majorly derived from agricultural residues such as coffee residue, [ 35 ] oil palm empty fruit bunch (EFB), [ 36 ] palm kernel shell (PKS), [ 2 ] bamboo, [ 37 ] glucose, [ 38 ] pine wood sawdust, [ 39 ] pine needle, [ 40 ] coconut shell, [ 6 ] cow dung, [ 41 ] sugarcane bagasse, [ 42 ] wood powder, [ 43 ] corn cobs, [ 44 ] orange peel, [ 45 ] rice husk, [ 46 ] murumuru kernel shell, [ 47 ] palm seed cake, [ 48 ] and so on. These low‐cost ubiquitous waste carbon precursors are not only nontoxic, noncorrosive, biodegradable, high availability, consist of high amount of carbon composition, but also uncomplicated to be processed as they do not require any pretreatment steps.…”

Preparation of Activated Carbon-Based Solid Sulfonic Acid and Its Catalytic Performance in Biodiesel Preparation

“…The conversion rate and the yield gradually decreased with the increase of repeated times, but it showed good catalytic effect when it was reused three times. The reason for the gradual decrease of the catalytic effect was mainly including the formation of sulfonate and exfoliation of sulfonic acid groups on the surface of AC-Ph-SO 3 H during the catalytic process (Zhang et al, 2021), which had an important relationship with the presence of methanol and the polar environment of the reaction system. After the catalyst was used for five times, the AC-Ph-SO 3 H was regenerated after being washed with methanol, dried, and sulfonated with concentrated sulfuric acid at 150 °C for 4 h. As shown in Figure 9, the density of -SO 3 H on the surface of AC-Ph-SO 3 H was only 0.27 mmol/g after being used for five times, while reached 0.67 mmol/g after regeneration, which was even slightly higher than that of the fresh catalyst.…”

Bimetallic MOF-Derived Synthesis of Cobalt-Cerium Oxide Supported Phosphotungstic Acid Composites for the Oleic Acid Esterification

“…As evident in Figure 8, the attainable level of the conversion increased from 41.4% to 57.9% with the rise of molar ratio of oleic acid to methanol from 1 : 20 to 1 : 40 at 1 h. However, when the reaction time was 3, 4, and 5 h, the conversion does not increase and even exhibited a decrease trend. is may be because too much methanol dilution effect reduces the collision frequency of reactant molecular species [38].…”