Access to hierarchically porous carbons from polymers and biopolymersviaa non-templating route has emerged as a promising strategy for a range of energy applications.

We develop a new concept to impart new functions to biocatalysts by combining enzymes and metal-organic frameworks (MOFs). The proof-of-concept design is demonstrated by embedding catalase molecules into uniformly sized ZIF-90 crystals via a de novo approach. We have carried out electron microscopy, X-ray diffraction, nitrogen sorption, electrophoresis, thermogravimetric analysis, and confocal microscopy to confirm that the ~10 nm catalase molecules are embedded in 2 μm single-crystalline ZIF-90 crystals with ~5 wt % loading. Because catalase is immobilized and sheltered by the ZIF-90 crystals, the composites show activity in hydrogen peroxide degradation even in the presence of protease proteinase K.

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Zeolitic imidazolate frameworks (ZIFs), a subclass of metal-organic frameworks (MOFs) built with tetrahedral metal ions and imidazolates, offer permanent porosity and high thermal and chemical stabilities. While ZIFs possess some attractive physical and chemical properties, it remains important to enhance their functionality for practical application. Here, an overview of the extensive strategies which have been developed to improve the functionality of ZIFs is provided, including linker modifications, functional hybridization of ZIFs via the encapsulation of guest species (such as metal and metal oxide nanoparticles and biomolecules) into ZIFs, and hybridization with polymeric matrices to form mixed matrix membranes for industrial gas and liquid separations. Furthermore, the developed strategies for achieving size and shape control of ZIF nanocrystals are considered, which are important for optimizing the textural characteristics as well as the functional performance of ZIFs and their derived materials/hybrids. Moreover, the recent trends of using ZIFs as templates for the derivation of nanoporous hybrid materials, including carbon/metal, carbon/oxide, carbon/sulfide, and carbon/phosphide hybrids, are discussed. Finally, some perspectives on the potential future research directions and applications for ZIFs and ZIF-derived materials are offered.

Biomass is a promising feedstock for the next generation drop-in liquid fuels and renewable chemicals, and hence the development of economically viable technologies for the production of commodity and specialty chemicals from sustainable biomass have received significant attention in recent years.While biomass transformation into drop-in biofuels involves multiple processing steps in which biomass is first depolymerized and converted to furfurals (5hydroxymethylfurfural, furfural), catalytic upgrading of furfurals is the most important step in achieving end products of the desired fuel properties. Several research articles have been published in the past decade reporting homogeneous and heterogeneous catalytic processes for upgrading furfurals to relevant drop-in fuel candidates such as, 2,5-dimethylfuran (DMF), 2methylfuran (2-MF), 5-ethoxymethylfurfural (EMF), γ-valorolactone (GVL), ethyl levulinate and long chain hydrocarbon alkanes. Although process technologies for the production and upgrading of some of these fuel compounds have been reviewed, a concise overview on production methodologies for all relevant furan based fuel compounds, including long chain hydrocarbon alkanes, from furfurals is yet to be published. This review article is aimed atpresenting an up to date analysis of the reported catalytic technologies for upgrading furfurals into long chain hydrocarbons with special emphasis on the condensation reactions for producing high carbon chain precursors and catalytic systems for their subsequent deoxygenation to achieve high yield and selectivity in fuel grade hydrocarbons. The current state-of-the-art on upgrading furfurals to DMF, 2-MF and EMF are also analyzed.

This review describes organometallic compounds and materials that are capable of mediating a rarely encountered but fundamentally important reaction: β-alkyl elimination at the metal-Cα-Cβ-R moiety, in which an alkyl group attached to the Cβ atom is transferred to the metal or to a coordinated substrate. The objectives of this review are to provide a cohesive fundamental understanding of β-alkyl-elimination reactions and to highlight its applications in olefin polymerization, alkane hydrogenolysis, depolymerization of branched polymers, ring-opening polymerization of cycloalkanes, and other useful organic reactions. To provide a coherent understanding of the β-alkyl elimination reaction, special attention is given to conditions and strategies used to facilitate β-alkyl-elimination/transfer events in metal-catalyzed olefin polymerization, which provide the well-studied examples.

The one-pot conversion of lignocellulosic and algal biomass into a liquid fuel, 2,5-dimethylfuran (DMF), has been achieved by using a multicomponent catalytic system comprising [DMA]⁺ [CH₃SO₃]⁻ (DMA=N,N-dimethylacetamide), Ru/C, and formic acid. The synthesis of DMF from all substrates was carried out under mild reaction conditions. The reaction progressed via 5-hydroxyemthylfurfural (HMF) in the first step followed by hydrogenation and hydrogenolysis of HMF with the Ru/C catalyst and formic acid as a hydrogen source. This report discloses the effectiveness of the Ru/C catalyst for the first time for DMF synthesis from inexpensive and readily abundant biomass sources, which gives a maximum yield of 32 % DMF in 1 h. A reaction route involving 5-(formyloxymethyl)furfural (FMF) as an intermediate has been elucidated based on the ¹H and ¹³C NMR spectroscopic data. Another promising biofuel, 5-ethoxymethylfurfural (EMF), was also synthesized with high selectivity from polymeric carbohydrate-rich biomass substrates by using a Brønsted acidic ionic liquid catalyst, that is [DMA]⁺ [CH₃SO₃]⁻, by etherification of HMF in ethanol.