Third-generation biofuels that are derived from microalgal biomass have gained momentum as a way forward in the sustainable production of biodiesel. Such efforts are propelled by the intention to reduce our dependence on fossil fuels as the primary source of energy. Accordingly, growing microalgal biomass in the form of suspended cultivation has been a conventional technique for the past few decades. To overcome the inevitable harvesting shortcomings arising from the excessive energy and time needed to separate the planktonic microalgal cells from water medium, researchers have started to explore attached microalgal cultivation systems. This cultivation mode permits the ease of harvesting mature microalgal biomass, circumventing the need to employ complex harvesting techniques to single out the cells, and is economically attractive. However, the main bottleneck associated with attached microalgal growth is low biomass production due to the difficulties the microalgal cells have in forming attachment and populating thereafter. In this regard, the current review encompasses the novel techniques adopted to promote attached microalgal growth. The physicochemical effects such as the pH of the culture medium, hydrophobicity, as well as the substratum surface properties and abiotic factors that can determine the fate of exponential growth of attached microalgal cells, are critically reviewed. This review aims to unveil the benefits of an attached microalgal cultivation system as a promising harvesting technique to produce sustainable biodiesel for lasting applications.

The global plastic production of 400 million tons/year has caused major catastrophes in marine environments. The current study, therefore, aimed to mitigate this challenge through the dissolution–reprecipitation method of eradicating impurities and contaminants from marine plastic debris. The results revealed that the rate of the dissolution of polyethylene (PE) outweighed polypropylene (PP) at lower temperatures. HDPE (high density polyethylene) and PP had optimal dissolution temperatures of 75 °C and 90 °C at 20 and 30 min, respectively, resulting in recovery percentages of 96.67% and 87.35% when applied to actual marine waste samples. Overall, this recycling method conserved the plastic quality and properties, making it a viable alternative for virgin plastics. The life cycle assessment (LCA) revealed that the drying stage demonstrated the greatest environmental impact within the system. The overall process, however, yielded a lower environmental impact in comparison with established findings. Conclusively, the current study has successfully restored marine plastic waste with high recovery rates and minimum chemical alterations, yielding a low environmental footprint.

The growth of black soldier fly larvae (BSFL) has been widely studied by feeding with myriad organic waste materials, transforming the wastes into a high-value

In recent decades, poor management of agri-food waste has imperiled the existing ecosystem and mankind with serious pollution issues. On the other side, mi In recent decades, poor management of agri-food waste has imperiled the existing ecosystem and mankind with serious pollution issues. On the other side, mi