PRIN LEVANTE 2020: Levulinic acid valorization through advanced novel technologies

The project LEVANTE deals with the development of new catalytic processes for the valorization of levulinic acid and its esters towards three classes of compounds: levulinic ketals, diphenolic acid and γ-valerolactone together with other reduction products

Il fondo epigrafico Petsas presso l’Università Ca’ Foscari Venezia: iscrizioni di Termo

Pubblicazione del più ingente lotto di decreti inediti di epoca ellenistica provenienti dal santuario di Termo, Etolia, dall'epoca del corpus del Klaffenbach (1932)

Levulinic acid production from the green macroalgae chaetomorpha linum and valonia aegagropila harvested in the orbetello lagoon

In recent years, the replacement of fossil resources with renewable ones has received great interest, especially as regards the production of new valuable bio-products and bio-fuels, in order to replace the traditional petroleum-based ones. In this context, the exploitation of waste biomasses into added-value biochemicals is strongly encouraged. Among these ones, the algae ones are attracting considerable attention, in particular macroalgae which cause eutrophication problems in estuaries and lagoons, due to the drastic reduction of dissolved oxygen during their decomposition. This is true for Orbetello lagoon (Italy), where a large amount of algal biomasses is removed every year through an expensive practice, with consequent environmentally serious disposal problems. In this work, for the first time, the acid-catalyzed conversion of two different macroalgae harvested in Orbetello lagoon, Chaetomorpha linum (Muller) Kutzing and Valonia aegagropila C. Agardh, into levulinic acid was studied and optimized, adopting a one-pot hydrothermal treatment, under microwave heating and in the presence of aqueous diluted mineral acids, H2SO4 and HCl. Levulinic acid is a versatile platform chemical, classified by the United States Department of Energy as one of the top-12 promising bio-based building blocks. The effect of the main reaction parameters to give levulinic acid was investigated and discussed, in particular the type and concentration of the acid catalyst, the temperature and the reaction time. The highest levulinic acid yields of 19 wt% for Chaetomorpha linum and 16 wt% for Valonia aegagropila, calculated respect to the weight of the starting dried biomass, were reached. The achieved results are very promising and confirm the significant potential of these green algae as renewable starting feedstocks for levulinic acid production

Integrated Cascade Process for the Catalytic Conversion of 5-Hydroxymethylfurfural to Furanic and TetrahydrofuranicDiethers as Potential Biofuels

The depletion of fossil resources is driving the research towards alternative renewable ones. Under this perspective, 5-hydroxymethylfurfural (HMF) represents a key molecule deriving from biomass characterized by remarkable potential as platform chemical. In this work, for the first time, the hydrogenation of HMF in ethanol was selectively addressed towards 2,5-bis(hydroxymethyl)furan (BHMF) or 2,5-bis(hydroxymethyl)tetrahydrofuran (BHMTHF) by properly tuning the reaction conditions in the presence of the same commercial catalyst (Ru/C), reaching the highest yields of 80 and 93 mol%, respectively. These diols represent not only interesting monomers but strategic precursors for two scarcely investigated ethoxylated biofuels, 2,5-bis(ethoxymethyl)furan (BEMF) and 2,5-bis(ethoxymethyl)tetrahydrofuran (BEMTHF). Therefore, the etherification with ethanol of pure BHMF and BHMTHF and of crude BHMF, as obtained from hydrogenation step, substrates scarcely investigated in the literature, was performed with several commercial heterogeneous acid catalysts. Among them, the zeolite HZSM-5 (Si/Al=25) was the most promising system, achieving the highest BEMF yield of 74 mol%. In particular, for the first time, the synthesis of the fully hydrogenated diether BEMTHF was thoroughly studied, and a novel cascade process for the tailored conversion of HMF to the diethyl ethers BEMF and BEMTHF was proposed

Integrated cascade biorefinery processes for the production of single cell oil by Lipomyces starkeyi from Arundo donax L. hydrolysates

Giant reed (Arundo donax L.) is a promising source of carbohydrates that can be converted into single cell oil (SCO) by oleaginous yeasts. Microbial conversion of both hemicellulose and cellulose fractions represents the key step for increasing the economic sustainability for SCO production. Lipomyces starkeyi DSM 70,296 was cultivated in two xylose-rich hydrolysates, obtained by the microwave-assisted hydrolysis of hemicellulose catalysed by FeCl3 or Amberlyst-70, and in two glucose-rich hydrolysates obtained by the enzymatic hydrolysis of cellulose. L. starkeyi grew on both undetoxified and partially-detoxified hydrolysates, achieving the lipid content of 30 wt% and yield values in the range 15–24 wt%. For both integrated cascade processes the final production of about 8 g SCO from 100 g biomass was achieved. SCO production through integrated hydrolysis cascade processes represents a promising solution for the effective exploitation of lignocellulosic feedstock from perennial grasses towards new generation biodiesel and other valuable bio-based products

Emotions and consumer's adoption of innovations: an integrative review and research agenda

The dominant models of innovation adoption have traditionally overlooked the role of emotions, despite the relevance of this construct in consumer decision-making. To address this historical gap, a notable stream of research on emotions in innovation adoption has emerged in recent years. To enrich our understanding of the psychology of innovation adoption, this paper integrates insights from research on emotions in psychology with a systematic review of the literature on consumer emotions in innovation adoption. Drawing on well-established theories of emotions and decision-making, we derive five fundamental dimensions that help define the role of emotions in the consumer adoption of innovations. A systematic review of existing evidence within the specific field of innovation adoption summarises the existing evidence through the lens of the five dimensions. The contributions of the paper are twofold. First, the paper offers a novel perspective that provides a deeper understanding of emotions as a psychological mechanism enabling or impeding innovation adoption. Second, we set an agenda for invigorating research in this important domain

Liquid hot water pretreatment of Arundo Donax: a comparison between batch and a flow-through systems

Lignocellulosic biomass is a valuable alternative raw material to partially substitute oil as both energy and chemical source. For example, polysaccharide constituents of lignocellulosic materials, hemicellulose and cellulose, can be hydrolytically depolymerized using acid catalysts or enzymes, while residual lignin can be used as a source of aromatic building blocks. The kinetic severity of the hydrolysis process can be adjusted to maximize alternatively the yields in fermentable sugars (bioethanol-way) or in chemicals such as furfural, hydroxymethylfurfural, levulinic acid. It is well known that, before performing the main hydrolysis step, a pretreatment stage of the matrix is necessary to cleave the bonds between hemicellulose, cellulose and lignin and to start breaking some of the polysaccharide chains. Liquid hot water (LHW) can be used for the pretreatment of biomass, without adding any acid to the system, thus avoiding the need of any subsequent neutralization step. In order to move toward industrial scale plant for production of energy and bulk chemicals from biomasses, continuous systems are desirable. An intermediate step toward the design of a continuous layout is constituted by semi-continuous processes. In this study, we have performed the LHW pretreatment of Arundo Donax (giant reed) in two different systems: a microwave (MW)-assisted batch reactor, where high heating rate can be achieved leading rapidly the system at the operative conditions of the pretreatment, and a fast heating flow-through layout in which the flow rate of the process water stream can be tuned. The achieved results highlight that in the microwave (MW)-assisted batch reactor good hemicelluloses solubilization, little sugar degradation and insignificant lignin and cellulose fractionation can be obtained by optimizing reaction temperature and time and that in the flow-through system high biomass conversion as well as very limited formation of degradation products can be obtained by adjusting the flow rate of the treatment water

Why consumer animosity reduces product quality perceptions: The role of extreme emotions in international crises

School of Business and Management, Queen Mary University of Londo

Tunable HMF hydrogenation to furan diols in a flow reactor using Ru/C as catalyst

5-hydroxymethylfurfural (HMF), accessible from various feedstocks, represents an important renewable platform-chemical, precursor for valuable biofuels and bio-based chemicals. In this work, the continuous hydrogenation of an aqueous solution of HMF to give strategic monomers, 2,5-bis(hydroxymethyl)furan (BHMF) and 2,5-bis(hydroxymethyl)tetrahydrofuran (BHMTHF) was investigated in a continuous flow reactor adopting a commercial Ru/C (5 wt%) as catalyst. The influence of the main process variables on products yield and selectivity was studied and optimized. The highest BHMF and BHMTHF yields of 87.9 and 93.7 mol%, respectively, were achieved by tuning the catalyst contact time, keeping all other variables constant (temperature, pressure, hydrogen flow rate, initial HMF concentration). Intraparticle diffusion limitation for hydrogen and HMF was shown to occur at some of the tested conditions by performing the HMF hydrogenation with different catalyst particle sizes, confirmed by calculations. Constant catalyst activity was observed up to 6 h time-on-stream and then gradually reduced. Fresh and spent catalyst characterization showed no significant sintering and negligible leaching of ruthenium during time-on-stream. A decrease of the specific surface area was observed, mainly due to humin deposition which is likely the reason for catalyst deactivation. Catalyst performance could be restored to initial values by a thorough washing of the catalyst