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A 100 ps laser is used to probe the pressure generation, depth of the non-solid ablator, and the non-linear optical effects through tamper materials. Samples consisted of an aluminum ablator with tampers of sapphire and coverslip glass. In general, the sapphire tamped sample achieves higher pressures at lower laser intensities as compared to the coverslip glass tamped sample. Attempts to model the details of this set of experimental data with standard available radiation coupled hydrodynamic codes make clear that more physics is needed in these simulations to accurately predict the impact of the tamper material on the pressure generation and the depth of non-solid aluminum. [ABSTRACT FROM AUTHOR]

The past decades have seen an increasing interest in developing pathways to produce bio-based chemicals from lignocellulosic biomass and organic waste as renewable resources. Using biomass as a source of chemical building blocks is critical to a future sustainable chemical industry. The successful development of bio-chemicals will also have a profound impact in terms of the innovations of new polymers and materials, new solvents, and new bio-active compounds. This article provides a broad review of conventional thermal heating, microwave processing, and biochemical processing for the production of value-added bio-based chemicals. The potentially important but currently little exploited microwave-assisted processes are given particular attention and the microwave-specific, non-thermal effects are explored. The comparative merits of different approaches are evaluated from the techno-economic and environmental perspectives. The opportunities of integrated biorefineries are articulated, with the aim to actualize carbon-efficient valorization of lignocellulosic biomass and organic waste for synthesizing an array of products. [ABSTRACT FROM AUTHOR]

The chemical industry is increasingly looking to develop bio-based alternatives to petroleum-based platform chemicals, in order to reduce dependence on diminishing fossil resources and to decrease GHG emissions. 5-Hydroxymethylfurfural (HMF) and 2,5-furandicarboxylic acid (FDCA) are two examples of bio-based chemicals which could allow for the synthesis of a wide range of chemicals and materials, particularly polymers, from renewable feedstocks. This review paper summarises and critically evaluates results from existing life cycle assessment (LCA) and technoeconomic analysis (TEA) studies of HMF and FDCA synthesis and, by doing this, provides several points of advice for future investigations and assessments of synthetic routes towards these bio-based products. Chemical considerations such as choice of solvent system, catalyst and energy production are reviewed; and methodological issues in LCA, such as treatment of biogenic carbon and allocation methods, are discussed. Overall, results suggest that the production of HMF and FDCA-based products may offer lower impacts from CO2 emissions than their fossil-based counterparts, but this often comes with an increase in environmental impacts in other impact categories. Higher operating costs from expensive fructose feedstocks and high energy demands also make HMF and FDCA less economically viable than current chemicals. Moving forwards, further investigation into different lignocellulosic feedstocks, energy production units and the development of new catalytic systems may help in making HMF and FDCA production more favourable than the production of fossil-based counterparts. [ABSTRACT FROM AUTHOR]

BACKGROUND Macroalgae are gaining increasing interest as an important biomass feedstock. Yet when valorising marine biomass, the presence of salt can pose a substantial obstacle to the effectiveness of downstream biological and chemical processes, as well as the engineering infrastructure required. Accordingly, dewatering, washing and drying are often considered the first and crucial primary steps in processing marine biomass such macroalgae. The high costs of these processes can make further marine biorefinery commercialisation prohibitive. This investigation assesses simple pre‐treatments for macroalgal biomass in saltwater, thereby reducing the freshwater footprint, and removing the need for an energy‐intensive washing and drying stage. RESULTS: Using acid and basic catalysts, the carbohydrate and soluble protein components were fractionated into a soluble aqueous phase, for further fermentation and a solid phase suitable for hydrothermal liquefaction. The presence of saltwater was found to aid the fractionation process, solubilising more of the biomass. The use of H2SO4 produced more monosaccharides, whereas NaOH solubilised higher levels of biomass at lower temperatures. The aqueous phase was demonstrated to be suitable for biological processing with the salt tolerant yeast Metschnikowia pulcherrima, and the residual solids suitable for processing via hydrothermal liquefaction. CONCLUSION: By contrast with existing pre‐treatment strategies, we demonstrate that an entirely salt‐based biochemical conversion route is a potentially viable option. For the first time this work demonstrates that, rather than a hindrance, the presence of saltwater can be advantageous, and could provide an alternative, more cost‐effective pathway to achieving a successful macroalgal‐based biorefinery. [ABSTRACT FROM AUTHOR]

Background: Microbial oils – often termed single cell oils (SCOs) – offer an alternative to terrestrial oil crops across the energy, food and chemical industries. In addition to oils, a range of secondary metabolites can be produced from the heterotrophic organisms as part of a biorefinery system. Techno‐economic analysis (TEA) is an important tool for evaluating economic viability, and although TEA is subject to high uncertainties where production is still at the laboratory scale, the tool can play a significant role in directing further research to evaluate suitability of scale‐up. Results: SCO production from the oleaginous yeast Metschnikowia pulcherrima using sucrose, wheat straw and distillery waste feedstocks was evaluated at two production scales. At a scale of 100 t year−1 oil production a minimum estimated selling price (MESP) of €14 000 t–1 was determined for sucrose. This reduced to €4–8000 t–1 on scaling to 10 000 t year−1, with sucrose and wheat straw yielding the lowest MESP. Conclusions: Feedstock price and lipid yield had the greatest impact on overall economic return, though the valorization of co‐products also had a large effect, and further play between feedstock and system productivity strategies could bring the price down to be competitive with terrestrial oils in the future. The novel approach demonstrated here for the first time integrates uncertainty into economic analysis whilst facilitating decision‐support at an early technology development stage. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: 2‐phenylethanol (2PE) is a fragrance molecule predominantly used in perfumes and the food industry. It can be made from petrochemicals inexpensively, however, this is unsuitable for most food applications. Currently, the main method of production for the bio‐derived compound is to extract the trace amounts found in rose petals, which is extremely costly. Potentially fermentation could provide an inexpensive, naturally sourced, alternative. RESULTS: In this investigation, 2PE was produced from the yeast Metschnikowia pulcherrima, optimised in flasks before scaling to 2 L batch and continuous operation. 2PE can be produced in high titres under de novo process conditions with up to 1500 mg L−1 achieved in a 2 L stirred bioreactor. This is the highest reported de novo titre to date, and achieved through high sugar loadings coupled with low nitrogen conditions. The process successfully ran in continuous mode also, with a concentration of 650 mg L−1 of 2PE being maintained. The 2PE production was further increased by the ex novo conversion of phenylalanine and semi‐continuous solid phase extraction from the supernatant. Under optimal conditions 14 000 mg L−1 of 2PE was produced. CONCLUSIONS: The work presented here offers a novel route to naturally sourced 2PE through a scalable fermentation with a robust yeast highly suited to industrial biotechnology. © 2018 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Marine litter, in particular plastic debris, poses a serious threat to marine life, human health and the economy. In order to reduce its impact, marine litter collections such as beach clean-ups are frequently conducted. This paper presents a systematic review of temporal developments, geographical distribution, quantities and waste treatment pathways of collected marine litter. Results from over 130 studies and projects highlight the worldwide increase in collection efforts. Many of these are in wealthy countries that do not primarily contribute to the problem. Over 250 thousand tonnes, have already been removed, but there is little or no information available regarding how this waste is treated or used post collection. This paper highlights the need for a whole-system quantitative assessment for the collection and waste treatment of marine litter, and identifies the challenges associated with utilising this waste in the future. [ABSTRACT FROM AUTHOR]

There is an increasing interest in the replacement of traditional plant based glyceride oils with microbial oils for fuel, food, dietary supplements and other pharmaceuticals and chemicals. To understand the environmental implications of this technology a systems approach is required. To date the majority of Life Cycle Assessment (LCA) studies have addressed the use of photoautotrophic (light stimulated growth, atmospheric carbon fixing) microbes to produce biofuels. But, with an increasing number of biotechnology companies using heterotrophic (non-light stimulated growth, requiring an organic carbon feedstock) microbes for large-scale industrial food and consumer goods production processes, it is important that the environmental implications of heterotrophic technology for products outside of the energy sector are better understood. This review assesses the current life cycle literature available that relates to heterotrophic algae and yeast microbial oil production, evaluating where current gaps in knowledge and uncertainties lie. It also includes relevant LCA information from other production processes. Overall, the review finds significant gaps relating to both life cycle inventory and impact assessment information. Improved industrial data sets are needed, particularly for novel feedstocks, and cultivation and downstream processing towards non-fuel products. The implications of synthetic biology also need to be addressed. Impact assessment does not currently include a broad range of impact categories, focusing predominately on energy use and climate change. And to answer wider implications questions, further LCA studies are needed that take a more consequential approach. Addressing these areas is vital to ensure commercial viability, sustainability and public acceptance of the technology going forward. [ABSTRACT FROM AUTHOR]

Abstract Macroalgae (seaweeds) represent an emerging resource for food and the production of commodity and specialty chemicals. In this study, a single-step microwave process was used to depolymerise a range of macroalgae native to the United Kingdom, producing a growth medium suitable for microbial fermentation. The medium contained a range of mono- and polysaccharides as well as macro- and micronutrients that could be metabolised by the oleaginous yeast Metschnikowia pulcherrima. Among twelve macroalgae species, the brown seaweeds exhibited the highest fermentation potential, especially the kelp Saccharina latissima. Applying a portfolio of ten native M. pulcherrima strains, yeast growth kinetics, as well as production of lipids and 2-phenylethanol were examined, with productivity and growth rate being strain dependent. On the 2 L scale, 6.9 g L−1 yeast biomass – a yield of 0.14 g g−1 with respect to the supplied macroalgae – containing 37.2% (w/w) lipid was achieved through utilisation of the proteins, mono- and polysaccharides from S. latissima , with no additional enzymes. In addition, the yeast degraded a range of fermentation inhibitors released upon microwave processing at high temperatures and long holding times. As macroalgae can be cultured to food grade, this system offers a novel, potentially low-cost route to edible microbial oils as well as a renewable feedstock for oleochemicals. Graphical abstract Unlabelled Image Highlights • Growth media generated from twelve macroalgae in a single-step microwave process. • Oleaginous Metschnikowia pulcherrima valorised macroalgal saccharides and proteins. • 6.9 g L−1 (0.15 g g−1) yeast with 37% lipid produced from the hydrolysed S. latissima • Versatility of M. pulcherrima could become key in a marine biorefinery. [ABSTRACT FROM AUTHOR]