Carbon-Based Nanocatalysts (CnCs) for Biomass Valorization and Hazardous Organics Remediation

Abstract

The continuous increase of the demand in merchandise and fuels augments the need of modern approaches for the mass-production of renewable chemicals derived from abundant feedstocks, like biomass, as well as for the water and soil remediation pollution resulting from the anthropogenic discharge of organic compounds. Towards these directions and within the concept of circular (bio)economy, the development of efficient and sustainable catalytic processes is of paramount importance. Within this context, the design of novel catalysts play a key role, with carbon-based nanocatalysts (CnCs) representing one of the most promising class of materials. In this review, a wide range of CnCs utilized for biomass valorization towards valuable chemicals production, and for environmental remediation applications are summarized and discussed. Emphasis is given in particular on the catalytic production of 5-hydroxymethylfurfural (5-HMF) from cellulose or starch-rich food waste, the hydrogenolysis of lignin towards high bio-oil yields enriched predominately in alkyl and oxygenated phenolic monomers, the photocatalytic, sonocatalytic or sonophotocatalytic selective partial oxidation of 5-HMF to 2,5-diformylfuran (DFF) and the decomposition of organic pollutants in aqueous matrixes. The carbonaceous materials were utilized as stand-alone catalysts or as supports of (nano)metals are various types of activated micro/mesoporous carbons, graphene/graphite and the chemically modified counterparts like graphite oxide and reduced graphite oxide, carbon nanotubes, carbon quantum dots, graphitic carbon nitride, and fullerenes.

Composites of Lignin-Based Biochar with BiOCl for Photocatalytic Water Treatment: RSM Studies for Process Optimization

“…The derived synergistic effects upon the composite formation and interaction of the inorganic–organic phase were expected to have a positive impact on the bifunctional adsorptive and photocatalytic remediation efficiency. This was expected not only for the narrowing of the E g in the case of the composite, but also for the well-known effect of the carbonaceous phase when it is used as fillers to favor the photoinduced e − /h + pairs separation and delocalization within the entire photocatalyst’s mass [ 62 , 64 , 65 ].…”

An efficient and practical approach for the continuous‐flow synthesis of 5‐hydroxymethylfurfural from carbohydrates using an acidic ionic liquid

“…The effectiveness of the solvent systems consisting of DMSO and H 2 O was investigated. The presence of water as a co‐solvent led to a decrease in 5‐HMF yield 68 . As a result, DMSO was chosen as the most effective solvent for the subsequent investigation.…”

“…The presence of water as a co-solvent led to a decrease in 5-HMF yield. 68 As a result, DMSO was chosen as the most effective solvent for the subsequent investigation.…”

First Report on a 1-Cycle Solid-Phase Extraction Method for Selective Separation of Am3+ and Eu3+: Use of BTP-Grafted Silica Decorated on Activated Carbon

“…A large number of reports on solid absorbents using alumina, zeolites, polymers, impregnated resins, silica, magnetic nanomaterials, and carbon-based materials (graphene oxide, CNT, and activated carbon) have appeared in the literature. − Activated carbon (AC) is a popular choice of absorbent among all those commonly used owing to its high surface area, porous structure, nontoxic nature, low cost, adsorption capacity, surface reactivity, thermal as well as chemical stability, and unlimited availability of natural carbon sources (agricultural waste). − Conceivably, the chemical modification of AC materials is an adaptable method to enhance their selectivity toward specific analytes. − Most frequently, –OH, –CHO, –COOH, and –COOR groups are utilized in the modification procedures.…”