Blackcurrant pomace (BCP) is an example of an annual, high-volume, under-utilized renewable resource with potential to generate chemicals, materials and bioenergy within the context of a zero-waste biorefinery. Herein, the microwave-assisted isolation, characterization and potential application of defibrillated lignocelluloses from depectinated blackcurrant pomace are reported. Depectination was achieved using citric acid (0.
View Article and Find Full Text PDFA sustainable, bio-based, mesoporous material, Starbon A800, was explored for use as an adsorbent in solid phase extraction (SPE). A solution containing seven nitrosamines was first used as a standard to optimise conditions for extraction efficiency with Starbon A800. After optimising conditions, 25 compounds of varying polarity (terpenes, phenolics, pesticides, PAHs, amines, and nitrosamines) were extracted with SPE using either Starbon® A800, C18 or Porous Graphitic Carbon (PGC) as the adsorbent, for comparison purposes.
View Article and Find Full Text PDFThe exploitation of unavoidable food supply chain wastes resulting from primary and secondary processing for chemicals, materials, and bioenergy is an important concept in the drive towards circular-based, resource-efficient biorefineries rather than petroleum refineries. The potential production of hydrogels (materials) from unavoidable food supply chain wastes, which are naturally rich in biopolymers such as cellulose, hemicellulose, pectin, and lignin, represents an interesting opportunity. However, these intertwined and interconnected biopolymers require separation and deconstruction prior to any useful application.
View Article and Find Full Text PDFZnO photoanodes in photoelectrochemical (PEC) water splitting for green-hydrogen production are limited due to the large bandgap that is only confined to UV light. One of the strategies for broadening the photo absorption range and improving light harvesting is to modify a one-dimensional (1D) nanostructure to a three-dimensional (3D) ZnO superstructure coupling with a narrow-bandgap material, in this case, a graphene quantum dot photosensitizer. Herein, we studied the effect of sulfur and nitrogen co-doped graphene quantum dot (S,N-GQD) sensitization on the surface of ZnO nanopencil (ZnO NPc) to give a photoanode in the visible light spectrum.
View Article and Find Full Text PDFCommercial ACs typically possess high surface areas and high microporosity. However, ACs with appreciable mesoporosity are growing in consideration and demand because they are beneficial for the adsorption of large species, such as heavy metal ions. Thus, in this study, degreased coffee grounds (DCG) were used as precursors for the production of ACs by means of chemical activation at 600 °C for the efficient removal of manganese in the form of MnO .
View Article and Find Full Text PDFPhosphorus is fast becoming a critical element, as the global supply and demand are reaching unsustainable levels. Herein, the synthesis, characterization, and applicability of a novel biomass-derived mesoporous carbonaceous material decorated with CeO (CeO-S400) as an efficient catalyst for the dephosphorylation of 4-nitrophenyl phosphate disodium salt hexahydrate are reported. The presence and distribution of CeO are evidenced by inductively coupled plasma mass spectrometry (ICP-MS) (118.
View Article and Find Full Text PDFCarbotrace 480 is a commercially available fluorescent optotracer that specifically binds to cellulose's glycosidic linkages. Herein, the use of Carbotrace 480 is reported as an analytical tool for linking cellulose content to hydrogel formation capability in defibrillated celluloses obtained from proprietary microalgae. Defibrillated celluloses obtained from acid-free hydrothermal microwave processing at low temperature (160 °C) showed poor hydrogel formation attributed to a low cellulose concentration as evidenced through the lack of Carbotrace fluorescence.
View Article and Find Full Text PDFSilver nanoparticles play a significant role in biomedical sciences due to their unique properties allowing for their use as an effective sensing and remediation platform Herein, the green synthesis of silver nanostructures (Ag NSs), prepared via aqueous extract of waste leaves in the presence of silver nitrate solution (10 M), is reported. The Ag NSs are fully characterized and their efficacy with respect to 4-nitrophenol reduction, glucose sensing, and microbes is determined. Visually, the color of silver nitrate containing solution altered from colorless to yellowish, then reddish grey, confirming the formation of Ag NSs.
View Article and Find Full Text PDFFood waste is a global problem, causing significant environmental harm and resulting in substantial economic losses globally. Bread is the commonly wasted food item in the developed world and presents a severe problem for the majority of European nations. It is the second most wasted food item in the UK after potatoes, with an equivalent of 20 million slices of bread thrown away daily.
View Article and Find Full Text PDFThe first production of defibrillated celluloses from microalgal biomass using acid-free, TEMPO-free and bleach-free hydrothermal microwave processing is reported. Two routes were explored: i. direct microwave process of native microalgae ("standard"), and ii.
View Article and Find Full Text PDFFor the first time, this work investigates the achievability of developing a biorefinery concept around almond hulls by hydrothermal treatment (HTT), thoroughly scrutinising the influence of the temperature (200-300 °C), pressure (100-180 bar), time (20-180 min) and solid loading (5-25 wt%). This process allowed the conversion of almond hulls into four main products: gas (2-13%), bio-oil (2-12%), aqueous (4-69%) and hydro-char (17-89%). The gas consisted of a mix of H, CO, CO and CH with a LHV fluctuating from 1 to 13 MJ/m STP.
View Article and Find Full Text PDFFloridoside (2-α-O-D-galactopyranosyl glycerol) is a glycerol glycoside that is biosynthesised by most species of red algae and has been implicated as an intracellular regulator of various homeostatic functions. Here, we report the identification of two unforeseen crystal forms of the ubiquitous natural osmolyte floridoside including a seemingly unheralded second anhydrous conformational polymorph and the unambiguous description of an elusive monohydrated variant. By employing a variety of thermal and spectroscopic techniques, we begin to explore both their macro and molecular physicochemical properties, which are notably different to that of the previously reported polymorph.
View Article and Find Full Text PDFAn integrated biorefinery approach using spent industrial ginger waste for resource recovery is reported. Valuable products including ginger oil, starch, microfibrillated cellulose (MFC), bio-oil and hydrochar were obtained. Approximately 4 % ginger oil, with a profile similar to commercial ginger oil, can be recovered via Soxhlet or Supercritical CO + 10 %EtOH extraction.
View Article and Find Full Text PDFIncreases in biological and non-biological pollutants pose a significant threat to environmental systems. In an effort to develop an effective means to treat such pollutants, the use of Phaseolus vulgaris (kidney beans) as reducing and capping agents is proposed for the green synthesis of highly stable silver nanoparticles (AgNPs) with a face-centered cubic (fcc) crystalline structure (size range: 10-20 nm). The potent role of the resulting AgNPs was found as triple platforms (photocatalyst, catalyst, and antimicrobial disinfectant).
View Article and Find Full Text PDFDeep eutectic solvents (DES) are one of the most promising green technologies to emerge in recent years given their combination of environmentally friendly credentials and useful functionalities. Considering the continued search for new DES - especially those that exemplify the aforementioned characteristics, we report the preparation of DES based on natural analogues of l-ascorbic acid for the first time. The onset of eutectic melting occurred at temperatures far below the melting point of the individual components and resulted in the generation of glass forming fluids with glass transition temperatures, viscosities and flow behavior that are comparable to similar systems.
View Article and Find Full Text PDFAntibiotic Microbial Resistance (AMR) is a major global challenge as it constitutes a severe threat to global public health if not addressed. To fight against AMR bacteria, new antimicrobial agents are continually needed, and their efficacy must be tested. Historically, many transition metals have been employed, but their cytotoxicity is an issue and hence must be reduced, typically by combination with organic polymers.
View Article and Find Full Text PDFCitrus juices from whole oranges and grapefruits (discarded from open market) and aqueous extracts from citrus processing waste (mainly peels) were used for bacterial cellulose production by DSM 15973. Grapefruit and orange juices yielded higher bacterial cellulose concentration (6.7 and 6.
View Article and Find Full Text PDFAs part of the biorefinery concept for spent coffee grounds (SCG), production of activated carbon (AC) was investigated from the degreased coffee grounds (DCG) left behind after oil extraction (primarily for biodiesel). The oils were extracted through conventional solvent extraction with GC/GC-MS confirming the oil was comparable to oils produced industrially. More significantly, analysis showed the DCG AC to have a four-fold increase in mesoporosity compared with the SCG AC with mesopore volumes of 0.
View Article and Find Full Text PDFA detailed design-of-experiment (DoE) study to investigate the cause-effect interactions of three process variables, that is, temperature (120-200 °C), holding time (0-30 min), and concentration (1.4-5.0 wt %), on the processing of citrus cellulosic matter using acid-free microwave-assisted selective scissoring (Hy-MASS) is reported.
View Article and Find Full Text PDFThe bio-based mesoporous materials made from polysaccharides, Starbons® can be modified by two different routes to give high levels of N-content, unexpectedly including significant quantities of nitrile groups which can improve the materials performance in applications including metal capture.
View Article and Find Full Text PDFIron-N-heterocyclic carbene complexes (Fe-NHCs) have come to prominence because of their applicability in diverse catalytic reactions, ranging from C-C cross-coupling and C-X bond formation to substitution, reduction, polymerization, and dehydration reactions. The detailed synthesis, characterization, and application of novel heterogeneous Fe-NHC catalysts immobilized on mesoporous expanded high-amylose corn starch (HACS) and Starbon 350 (S350) for facile fructose conversion into 5-hydroxymethylfurfural (HMF) is reported. Both catalyst types showed good performance for the dehydration of fructose to HMF when the reaction was tested at 100 °C with varying time (10 min, 20 min, 0.
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