Addition of Activated Carbon into a Cattle Diet to Mitigate GHG Emissions and Improve Production

A state-of-art review on the redox activity of persistent free radicals in biochar

Biochar-bound persistent free radicals (biochar-PFRs) attract much attention because they can directly or indirectly mediate the transformation of contaminants in large-scale wastewater treatment processes. Despite this, a comprehensive top-down understanding of the redox activity of biochar-PFRs, particularly consumption and regeneration mechanisms, as well as challenges in redox activity assessment, is still lacking. To tackle this challenge, this review outlines the identification and determination methods of biochar-PFRs, which serve as a prerequisite for assessing the redox activity of biochar-PFRs. Recent developments concerning biochar-PFRs are discussed, with a main emphasis on the reaction mechanisms (both non-free radical and free radical pathways) and their effectiveness in removing contaminants. Importantly, the review delves into the mechanism of biochar-PFRs regeneration, triggered by metal cations, reactive oxygen species, and ultraviolet radiations. Furthermore, this review thoroughly explores the dilemma in appraising the redox activity of biochar-PFRs. Components with unpaired electrons (particular defects and metal ions) interfere with biochar-PFRs signals in electron paramagnetic resonance spectra. Scavengers and extractants of biochar-PFRs also inevitably modify the active ingredients of biochar. Based on these analyses, a practical strategy is proposed to precisely determine the redox activity of biochar-PFRs. Finally, the review concludes by presenting current gaps in knowledge and offering suggestions for future research. This comprehensive examination aims to provide new and significant insights into the redox activity of biochar-PFRs.

Biochar as a feed supplement for nutrient digestibility and growth performance of Catla catla fingerlings

The purpose of the current research was to determine the impact of various biochar supplements on nutrient digestibility and growth performance of Catla catla fingerlings fed on Moringa oleifera seed meal (MOSM) based diet. An experiment with 90 days of feeding was conducted to investigate the efficacy of biochar obtained from different sources such as parthenium, farmyard manure, poultry waste, vegetable waste, and corncob waste at 2 mg/kg. There were15 fingerlings in each tank in the triplicate set of tanks. Fingerlings were fed at the rate of 5 % of their live wet weight. From each tank, feces were collected twice daily and stored to determine nutrient digestibility. Results showed that poultry waste biochar (test diet-IV) at 2 mg/kg was the best source to significantly (P < 0.05) improve weight gain % (256.58 %) and feed conversion ratio (1.19) than the other biochar sources and control diet. Furthermore, in terms of nutrient digestibility, optimum fat (81.90 %), protein (75.92 %), and gross energy (74.84 kcalg⁻¹) values were obtained by using the same type of biochar (poultry waste). Conclusively, among all the five biochar sources, poultry waste biochar proved to be the best one, improving fish body performance.

Biochar for agronomy, animal farming, anaerobic digestion, composting, water treatment, soil remediation, construction, energy storage, and carbon sequestration: a review

In the context of climate change and the circular economy, biochar has recently found many applications in various sectors as a versatile and recycled material. Here, we review application of biochar-based for carbon sink, covering agronomy, animal farming, anaerobic digestion, composting, environmental remediation, construction, and energy storage. The ultimate storage reservoirs for biochar are soils, civil infrastructure, and landfills. Biochar-based fertilisers, which combine traditional fertilisers with biochar as a nutrient carrier, are promising in agronomy. The use of biochar as a feed additive for animals shows benefits in terms of animal growth, gut microbiota, reduced enteric methane production, egg yield, and endo-toxicant mitigation. Biochar enhances anaerobic digestion operations, primarily for biogas generation and upgrading, performance and sustainability, and the mitigation of inhibitory impurities. In composts, biochar controls the release of greenhouse gases and enhances microbial activity. Co-composted biochar improves soil properties and enhances crop productivity. Pristine and engineered biochar can also be employed for water and soil remediation to remove pollutants. In construction, biochar can be added to cement or asphalt, thus conferring structural and functional advantages. Incorporating biochar in biocomposites improves insulation, electromagnetic radiation protection and moisture control. Finally, synthesising biochar-based materials for energy storage applications requires additional functionalisation.