Opportunities for improving biodiesel production via lipase catalysis

The primary means of immobilizing enzymes are to boost the enzyme productivity and operational stability, alongside facilitating the reuse of enzymes. Notwithstanding the aforementioned benefits, enzyme immobilization promotes high catalytic activity and stability, convenient handling of enzymes, in addition to their facile separation from reaction mixtures without contaminating the products. This review describes the choices of support materials and cross-linkers together with several mechanisms that influence the performance, stabilization and hyperactivation of immobilized enzymes. Altering enzyme properties often changes the enzyme structure due to random modifications in the behavior, which in some cases can be positive or negative. Future strategy to develop new generations of immobilized enzymes should capitalize on the rapid advances of genetic manipulation, organic chemistry, computational chemistry and bioinformatics, reactor and reaction design. Upcoming efforts to improve enzymes as industrial biocatalysts must consider their development for increased selective promiscuity suitable for multiple biotransformations, either independently or as catalytic cascade processes thereby enhance the cost-effectiveness of the processes.

On the taught new tricks of enzymes immobilization: An all-inclusive overview

This tutorial review focuses on recent advances in technologies for enzyme immobilisation, enabling their cost-effective use in the bio-based economy and continuous processing in general. The application of enzymes, particularly in aqueous media, is generally on a single use, throw-away basis which is neither cost-effective nor compatible with a circular economy concept. This shortcoming can be overcome by immobilising the enzyme as an insoluble recyclable solid, that is as a heterogeneous catalyst.

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New frontiers in enzyme immobilisation: robust biocatalysts for a circular bio-based economy

Enzyme co-immobilization: Always the biocatalyst designers' choice…or not?

The depletion of fossil fuel reserves and increased environmental concerns related to fossil fuel production and combustion has forced the global communities to search for renewable fuels. In this regard, microalgae-based biodiesel has been considered as one of the interesting alternatives. Biodiesel production from the cultivation of microalgae is eco-friendly and sustainable. Moreover, microalgae have several advantages over other bioenergy sources, including their good photosynthetic capacity and faster growth rates. The productivity of microalgae per unit land area is also significantly higher than that of terrestrial plants. The produced microalgae biomass is rich with high quality lipids, which can be converted into biodiesel by transesterification reactions. Generally, the transesterification reactions are carried out in the presence of a homogeneous or heterogeneous catalyst. The homogeneous catalysts have many disadvantages, including their single use, slow reaction rate and saponification issues due to the presence of fatty acids in the feedstock. The acidic nature of the homogeneous catalysts also causes equipment corrosion. On the other hand, the heterogeneous catalysts offer several advantages, including their reusability, higher reaction rate and selectivity, easy product/catalyst separation and low cost. Due to these facts, the development of solid phase transesterification catalysts have been receiving growing interest. The present review is focused on the use of heterogeneous catalysts for biodiesel production from microalgal oil as a reliable feedstock with a comparison to other available feedstocks. It also highlights optimal reaction conditions for maximum biodiesel yields, reusability of the solid catalysts, cost, and environmental impact. The superior lipid content of microalgae and the efficient concurrent esterification and transesterification of the solid acid−base catalysts can offer new advancements in biodiesel production.

Application of Heterogeneous Catalysts for Biodiesel Production from Microalgal Oil—A Review

Recent advances in nano-carrier immobilized enzymes and their applications

A Dye-Sensitized Solar Cells with Enhanced Efficiency Based on a “Pillared Effect” of CoMoP2@Mxene@CNTs Composite Counter Electrode

Carbon-based all-inorganic CsPbIxBr3-x perovskite solar cells offer high stability against heat and humidity and a suitable band gap for tandem and semitransparent photovoltaics. In CsPbIxBr3-x perovskite films, the defects at grain boundaries (GBs) cause charge trapping, reducing the efficiency of the cell. Electronic deactivation of GB has been a conventional strategy to suppress the trapping, but at the cost of charge carrier transport through the boundaries. Here, we turn the GBs into benign charge transport pathways with the aid of bipolar charge transport semiconductors, namely, Ti3C2TX (MXene) and Spiro-OMeTAD, respectively. Thanks to the synergistic effects of both n- and p-type transport media, the charge transport is improved and balanced at the GBs. As a result, the cells achieve an efficiency of 12.7%, the highest among all low-temperature-processed carbon-based inorganic perovskite solar cells. Benign GBs also lead to enhanced light and aging stabilities. Our work demonstrates a proof-of-concept strategy of benign electronic modulation of GBs for solution-processed perovskite solar cells.

Chen Dong

Papers

Recent advances in nano-carrier immobilized enzymes and their applications

A Dye-Sensitized Solar Cells with Enhanced Efficiency Based on a “Pillared Effect” of CoMoP2@Mxene@CNTs Composite Counter Electrode

Synergistic Effects of Bipolar Additives on Grain Boundary-Mediated Charge Transport for Efficient Carbon-Based Inorganic Perovskite Solar Cells.

NiOx for interface and work function engineering in carbon-based all-inorganic perovskite solar cells.

A Dye-Sensitized Solar Cells Based on Comop2@Mxene@Cnts Composite Counter Electrode with “Pillared Effect” Generated an Efficiency of 10.64%