The tremendous amount of food waste from diverse sources is an environmental burden if disposed of inappropriately. Thus, implementation of a biorefinery platform for food waste is an ideal option to pursue (e.g., production of value-added products while reducing the volume of waste). The adoption of such a process is expected to reduce the production cost of biodegradable plastics (e.g., compared to conventional routes of production using overpriced pure substrates (e.g., glucose)). This review focuses on current technologies for the production of polyhydroxyalkanoates (PHA) from food waste. Technical details were also described to offer clear insights into diverse pretreatments for preparation of raw materials for the actual production of bioplastic (from food wastes). In this respect, particular attention was paid to fermentation technologies based on pure and mixed cultures. A clear description on the chemical modification of starch, cellulose, chitin, and caprolactone is also provided with a number of case studies (covering PHA-based products) along with a discussion on the prospects of food waste valorization approaches and their economic/technical viability.

Gold nanoparticles (GNPs) have generated keen interest among researchers in recent years due to their excellent physicochemical properties.

Metal–organic frameworks (MOFs) have potential as air quality treatment media for various gaseous pollutants (e.g., ammonia) through diverse mechanisms (capture and catalytic degradation). A broad range of MOFs have been developed with numerous advantageous properties (e.g., high surface area, high degree of porosity, intrinsically tunable chemical structure, flexible architecture, and multifunctional properties) to meet strict air quality metrics. Nevertheless, the practical use of these novel materials has also been restricted due to certain drawbacks including high fabrication costs, poor selectivity, low capacity, and difficulties in recycling/regeneration. This review was organized to highlight the recent advancements in MOF technology for the mitigation of ammonia. The article aims to expand the use of MOFs in air quality treatments by identifying the research gaps in associated fields.