Showing papers by "Robert G. J. Edyvean published in 2018"
TL;DR: In this paper, the toxic and inhibitory effects of caffeic acid on biogas production as well as its ultimate anaerobic biodegradability were investigated. But, little is known about the reactive adaption processes taking place with the acid in sludge, or about the effects on extracellular polymeric substances (EPS).
Abstract: Caffeic acid in waste comes from a variety of industries, and its disposal is likely to increase due to emerging processes such as graphene production and use in healthcare products. The current sustainable option to treat waste caffeic acid and prevent its natural transformation in soil to greenhouse gases, is anaerobic digestion. However, little is known about the toxic and inhibitory effects of caffeic acid on biogas production as well as its ultimate anaerobic biodegradability; or about the reactiveadsorptive processes taking place with caffeic acid in sludge, metabolic intermediates, thermodynamic limitations and the effects on extracellular polymeric substances (EPS). Standard methods revealed that 80% of biogas production (EC 80 ) from a readily digestible biomass was inhibited at 389 mg caffeic acid·g -1 VSS. Up to 52% of caffeic acid was biodegraded. β-oxidation and reductive dehydroxylation were the initial activation reactions transforming caffeic acid into typical polyphenol structural units (protocatechuic acid and 4HBA). Adsorption of caffeic acid (53.3% and 28.6%) to the sludge occurred even at inhibitory concentrations. The EPS structure remained unchanged regardless of the increase in concentration of caffeic acid. Reasonable concentrations of caffeic acid could be co-digested with a similar readily digestible biomass with an expected reduction in biogas production. It is feasible to treat waste caffeic acid by anaerobic digestion and adsorption of its derivates, in order to reduce the contribution to global warming and to protect the environment. Keywords: anaerobes, anaerobic digestion, biogas, biomass, caffeic acid, graphene, inhibition, polyphenols, renewable energy, toxicity, wastewater
4 citations
TL;DR: Sorby as mentioned in this paper is best known to geologists for his pioneering use of the petrological microscope and for instigating the systematic study of fluid inclusions, and also introduced microscopy to many other areas of science.
Abstract: Henry Clifton Sorby (1826–1908) is best known to geologists for his pioneering use of the petrological microscope and for instigating the systematic study of fluid inclusions. He also introduced microscopy to many other areas of science. Sorby belongs to that great tradition of amateurs who have made substantial contributions to science. Being unhindered by the needs of funding bodies, Sorby’s research ranged widely and touched on many topics that are still current today.