Nanostructured Metal Catalysts for Selective Hydrogenation and Oxidation of Cellulosic Biomass to Chemicals

Abstract

Conversion of biomass to chemicals provides essential products to human society from renewable resources. In this context, achieving atom‐economical and energy‐efficient conversion with high selectivity towards target products remains a key challenge. Recent developments in nanostructured catalysts address this challenge reporting remarkable performances in shape and morphology dependent catalysis by metals on nano scale in energy and environmental applications. In this review, most recent advances in synthesis of heterogeneous nanomaterials, surface characterization and catalytic performances for hydrogenation and oxidation for biorenewables with plausible mechanism have been discussed. The perspectives obtained from this review paper will provide insights into rational design of active, selective and stable catalytic materials for sustainable production of value‐added chemicals from biomass resources.

Electronically Coupled PtCo/MgAl Hydrotalcite Catalysts Display Tunable Selectivity Toward Glyceric Acid and Lactic Acid for Glycerol Conversion

“…As already confirmed in previous studies [37,[49][50][51], glycerol conversion gives glyceraldehyde (GLA) as the primary oxidation product. If adsorption strength of GLA is strong on metallic catalyst surface, GLA could be further converted to GLYA as an important product for glycerol conversion (Fig.…”

“…As diffraction peaks at 13°, 23°, 35°, 39° and 47° are assigned to typical layered structures of MgAl hydrotalcite framework with low surface index numbers (See Fig. 3a) for Pt-cp, PtCo(1)-sol-gel and PtCo(1) cp catalysts [37], we find that peaks at 61° and 63° ascribed to (440) facet display detectable blue shift towards lower diffraction angle, as Co species are present in LDH framework [38][39][40][41][42][43]. It suggests that PtCo nanoparticles interact strongly with (440) lattice with high concentration of unsaturated surface sites [41].…”

Liquid-Phase Oxidation of Ethylene Glycol on Pt and Pt–Fe Catalysts for the Production of Glycolic Acid: Remarkable Bimetallic Effect and Reaction Mechanism

“…Effect of initial EG concentration on the EG reaction rate with Pt catalyst is also dramatically different for the neutral and alkaline conditions (Figure 5). Under neutral conditions, the reaction rate increases very rapidly with an increase in initial EG concentration from 0.15 kmol/m 3 to 0.6 kmol/m 3 but remains constant at EG concentrations greater than 0.6 kmol/ m 3 . In contrast, a strong inhibition effect was observed for the EG oxidation rate under alkaline conditions, with respect to EG concentration.…”

Hydrogenolysis of Glycerol to Propylene Glycol: Energy, Tech-Economic, and Environmental Studies

“…Both CHDO and CTH plant studied in this work consist of three main units: pretreatment unit, hydrogenolysis unit where glycerol is converted into PG and other co-products, and separation and purification unit. In this work, reaction results over Ni/Cu/TiO 2 catalyst were used for simulation of CHDO process ( Cai et al, 2018 ; Jin et al, 2019a ; Jin et al, 2019b ; Xia et al, 2020 ; Yin et al, 2020 ). Ni/Cu/TiO 2 catalyst was selected for CHDO process because it displays leading performances in conversion and PG selectivity in literature.…”

“…Catalytic transfer hydrogenolysis (CTH), which takes use of renewable H-donors in liquid medium, is considered as one of the most economically and environmentally beneficial technique to substitute conventional hydrogenolysis processes (CHDO, Figure 1 ). ( Jin et al, 2019b ; Zhang et al, 2020a ; Yin et al, 2020 ; Nie et al, 2021 ). Much milder reaction temperatures, higher intrinsic hydrogenolysis rates in aqueous medium, and lower operating pressures in the absence of externally added H 2 make CTH processes more energy and atom efficient compared with CHDO processes.…”