Amorphous Carbon with SO₃H Groups as a Solid Brønsted Acid Catalyst

Abstract

Homogeneous Brønsted acid catalysts such as H2SO4 and HCl are used for the production of industrially important chemicals. However, their use requires significant energy costs for separation, reuse, and treatment of salt wastes. Alternatively, heterogeneous Brønsted acid catalysts are promising candidates that can decrease the environmental impact associated with chemical production. In this review, we highlight amorphous carbon bearing SO3H groups as an insoluble Brønsted acid available for various acid-catalyzed reactions.

Synthesis of bio-additives: transesterification of ethyl acetate with glycerol using homogeneous or heterogeneous acid catalysts

“…These advantages can compensate the problems arising by homogeneous Brönsted acid catalysts in industrial transesterification processes. 37 Interestingly, catalyses promoted by Amberlyst-15 (dry) and -16 (wet) acid resins ( Figure 4) were quite similar to each other and led to a mixture of mono, di and triacetins with a large predominance of diacetin. Aiming to attain total glycerol conversion and the equilibrium selectivity for both resins, the reaction was carried out on Amberlyst-15 (dry) and Amberlyst-16 (wet), under the same conditions showed in Figure 4, except for the glycerol:EtOAc ratio.…”

Functional carbons and carbon nanohybrids for the catalytic conversion of biomass to renewable chemicals in the condensed phase

“…A general synthetic approach for the so-called "sugar catalyst" typically consists in the partial carbonization of the carbohydrate substrates through pyrolysis at 200-300 ºC followed by refluxing with sulfuric acid to generate sulfonic functional groups [72][73][74]. The thermally carbonized material typically displays a surface area of less than 5 m 2 /g that is independent from the pyrolysis temperature and sulfonation conditions [74]. The produced carbons were reported to have a sheet-like structure containing 1.2-1.3 nm aromatic domains, structurally similar to graphene [74].…”

“…The thermally carbonized material typically displays a surface area of less than 5 m 2 /g that is independent from the pyrolysis temperature and sulfonation conditions [74]. The produced carbons were reported to have a sheet-like structure containing 1.2-1.3 nm aromatic domains, structurally similar to graphene [74].…”

“…These carbons were also used for the esterification of long chain fatty acids and transesterification of triglycerides to produce biodiesel [74,[81][82][83]. Despite the low surface area, the Cellulose-Derived Carbon Solid Acids (CCSA) exhibit a higher -SO3H loading, activity, and product yield when compared to commercially available solid acid catalysts, such as Amberlyst-15, Nafion, H-mordenite, or niobic acid.…”

Magnetic core–shell Fe3O4@C-SO3H nanoparticle catalyst for hydrolysis of cellulose

“…Various of solid acid catalysts, such as the sulfonated carbon materials (Toda et al 2005;Nakajima and Hara 2012;Van de Vyver et al 2010;Pang et al 2010;Onda et al 2008;Suganuma et al 2008), ionexchange resins (Rinaldi et al 2008), heteropolyacids (Tian et al 2010) and transition-metal oxide (Takagaki et al 2008;Nakajima et al 2011), etc., have been found active for the hydrolysis of cellulose. In particular, the sulfonated carbon catalysts were widely studied since Hara et al (Toda et al 2005) reported it effective for biodiesel production from vegetable oil.…”