Approximately 99% of the plastics used in the packaging industry today are petroleum-based. However, the adoption of biobased plastics could help to greatly reduce the environmental footprint of packaging materials and help to conserve our non-renewable petroleum resources. This tutorial review provides an overview of renewable polyesters and their potential packaging materials.
The massive consumption of fossil fuels and associated environmental issues are leading to an increased interest in alternative resources such as biofuels. The renewable biofuels can be upgraded from bio-oils that are derived from biomass pyrolysis. Catalytic cracking and hydrodeoxygenation (HDO) are two of the most promising bio-oil upgrading processes for biofuel production. Heterogeneous catalysts are essential for upgrading bio-oil into hydrocarbon biofuel. Although advances have been achieved, the deactivation and regeneration of catalysts still remains a challenge. This review focuses on the current progress and challenges of heterogeneous catalyst application, deactivation, and regeneration. The technologies of catalysts deactivation, reduction, and regeneration for improving catalyst activity and stability are discussed. Some suggestions for future research including catalyst mechanism, catalyst development, process integration, and biomass modification for the production of hydrocarbon biofuels are provided.
To address the issues of greenhouse gas emissions associated with fossil fuels, vegetable oilseeds, especially non-food oilseeds, are used as an alternative fuel resource. Vegetable oil derived from these oilseeds can be upgraded into hydrocarbon biofuel. Catalytic cracking and hydroprocessing are two of the most promising pathways for converting vegetable oil to hydrocarbon biofuel. Heterogeneous catalysts play a critical role in those processes. The present review summarizes current progresses and remaining challenges of vegetable oil upgrading to biofuel. The catalyst properties, applications, deactivation, and regeneration are reviewed. A comparison of catalysts used in vegetable oil and bio-oil upgrading is also carried out. Some suggestions for heterogeneous catalysts applied in vegetable oil upgrading to improve the yield and quality of hydrocarbon biofuel are provided for further research in the future.
A tertiary amine (N,N-dimethylcyclohexylamine, CyNMe2) was used as a switchable hydrophilicity solvent (SHS) for extracting phospholipids (PLs) from raw cream (RC), buttermilk (BM), concentrated buttermilk (CBM), and beta-serum (BS). The SHS extractions were performed with varying solvent–sample weight ratio at room temperature. The extracted PLs using CyNMe2 were recovered by bubbling CO2 at atmospheric pressure, switching the CyNMe2 into its respective salt. For comparison, the PLs were also extracted using Folch (FE) and Mojonnier (ME) extraction. The extraction efficiency of SHS varied from 0.33% to 99%, depending on the type of byproduct. The SHS extracted up to 99% of the PLs directly from BM, while only 11.37% ± 0.57% and 2.66% ± 0.56% of the PLs were extracted with FE and ME, respectively. These results demonstrate the applicability of SHS for the extraction of PLs from dairy byproducts.