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Nowadays only little information (mainly by GC­MS) about the chemical nature of HTL oils is available. In the present work different standard and improved analytical techniques were tested as additional tools for the chemical characterization of HTL oils: analytical pyrolysis (Py­GC­MS), TGA and a novel stepwise Py­SPME­GC­MS were tested for the first time. By coupling these different techniques, we could establish the chemical nature of the fractions not amenable for standard oil analysis techniques (GC­MS, silylation or transesterification). In the case of 200°C HTL the high molecular weight substances mainly consisted in algaenans derived materials, whereas a low amount of proteins (or protein containing macromolecules) ended up in the HTL oil. In the case of 300°C HTL oil, the mass fraction of the HTL products originated from non­lipidic material degradation as well as “protein” content of the oil were identified and the resulting high nitrogen content present in the 300°C HTL oil was explained., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 134-141

The exploitation of aquatic biomass for energetic purpose is a promising field of research. Chlamydomonas reinhardtii is a deeply investigated microalga able to convert sunlight into chemical energy by indirect photolysis under specific culture conditions, allowing the production of a hydrogen rich biogas and algal biomass as side-product. Besides the hydrogen production, a valorisation of “spent” side-products is a key point for the process optimization, for the maximization of process energetic yield and the reduction of photo-biogenic hydrogen prices. The aim of this work was to investigate the potential conversion of Chlamydomonas reinhardtii exhaust biomass to bio-diesel, pyrolysis oil and nitrogen rich charcoal (bio-char). Microalgal fats were obtained through a standard extraction (15% wlipids/wbiomass yield). Then, the extraction residue, mainly characterised by proteins and cellulose, was pyrolysed at 350°C using a bench scale pyrolyser, in order to convert the raw biomass into bio-oil and bio-char. The major pyrolysis product resulted to be bio-char (45% mass yield), whereas a lower amount of pyrolysis oil (25% mass yield) was obtained. Bio-oil was mainly formed by cellulose pyrolysis products (55% w/wbio-oil mainly anhydrosugars, anhydro-oligomers and small polysaccharides). On the other hand the feedstock proteins played the most important role in bio-char formation., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 455-458

The massive use of lithium batteries in industries, such as automotive and electrical network accumulation, requires the development of safer electrolytes, economic and possibly made from renewable resources using eco-friendly processes. In this work, we reported the synthesis and the physico-chemical and functional characterization of a polymer gel electrolyte (GPE) based on a skeleton of polyhydroxyalkanoate obtained from biomass by means of an easy and environmentally friendly chemical process. The GPE has an ionic conductivity of 0.8 mS cm−1 at room temperature, is thermally stable up to over 100 °C and is not flammable. The electrochemical stability window is higher than 5 V. The cell Li/GPE/LiFePO4 shows specific capacity of 100 mAhg−1 at 3C with 100% coulombic efficiency. These results demonstrate that the GPE based on polyhydroxyalkanoate is very promising for use in lithium batteries of high power density.

Polyhydroxyalkanoates (PHA) are a key constituent of excess sludge produced by Aerobic Sewage Sludge Treatment plants. The accumulation of significant amount of PHA inside aerobic microbial cells occurs when a surplus of an easily degradable carbon source (e.g., volatile fatty acids, VFA) is found in combination with other nutrients limitation. Herein, hydrothermal treatment (HT) of PHA-containing sludge at 300 and 375 °C was demonstrated to be effective in converting most (>70% w/w) of the bacterial PHA stored inside microbial cells into alkene/CO2 gas mixtures. Simultaneously, most of non-PHA biomass was converted into water-soluble compounds (50% carbon yield) that were acidogenic fermented to produce volatile fatty acids, ideal substrate to feed aerobic bacteria and produce more PHA. According to results here presented, HT of excess sludge with moderate (13%) PHA content can produce about 50 kg of alkenes per tonne of suspended solids treated, with a significant reduction of sludge mass (80% reduction of wet sludge volume) and consequent disposal cost.

Recent research studies have shown that the intra-skeletal organic matrix of corals contains lipids. This communication reports their characterization and their influence on calcium carbonate precipitation. In addition, their potential role in coral's biomineralization is discussed.

Flocculation induced by pH decrease is here presented as a solution to pre-concentrate algal cultures of species belonging to Scenedesmaceae and preserve the integrity of the biomass, while maintaining the photosynthetic capacity of non-harvested cells. The low-pH flocculation method gives highly effective results exclusively by the strength of the acid (hydrochloric or formic) used for the treatment, and is applicable to cultures having high cell densities (> 2 g L− 1). High flocculation efficiencies (> 90%) are obtained also by using heterogeneous acids, such as solid acid carbons from naturally available compounds, which are proposed as cheap recyclable materials to be exploited for this purpose. Additionally, the potential reuse of the filtered medium (sterilized or not) and of the supernatant (containing non-harvested cells) is investigated to avoid great water losses and to re-inoculate new cultures.

This article describes the toxic effects of imidazolium ionic liquids bearing alkyl (BMIM), monoethoxy (MOEMIM), and diethoxy (M(OE)(2)MIM) side chains toward two marine diatoms, Skeletonema marinoi and Phaeodactylum tricornutum. MOEMIM and M(OE)(2)MIM cations showed a lower inhibition of growth and photosynthetic efficiency with respect to their alkyl counter part, with both algal Species. However, a large difference in sensitivity was found between S. marinoi and P. tricornutum, the first being much more Sensitive to the action of ionic liquids than the second one. The effects of salinity on BMIM Cl toxicity toward S. marinoi revealed that a decrease from salinity 35 to salinity 15 does not influence the biological effects toward the alga. Finally, Fourier transform infrared (FT-IR) microscopy of alga cells after ionic liquids exposure allowed us to detect an alteration of the organic cellular components related. to silica uptake and organization. On the basis of these results, the different behavior of the two diatom species can be tentatively ascribed to different silica uptake and organization in outer cell walls

The squid pen (gladius) from the Loligo vulgaris was used for preparation of β-chitin materials characterized by different chemical, micro- and nano-structural properties that preserved, almost completely the macrostructural and the mechanical ones. The β-chitin materials obtained by alkaline treatment showed porosity, wettability and swelling that are a function of the duration of the treatment. Microscopic, spectroscopic and synchrotron X-ray diffraction techniques showed that the chemical environment of the N-acetyl groups of the β-chitin chains changes after the thermal alkaline treatment. As a consequence, the crystalline packing of the β-chitin is modified, due to the intercalation of water molecules between β-chitin sheets. Potential applications of these β-chitin materials range from the nanotechnology to the regenerative medicine. The use of gladii, which are waste products of the fishing industry, has also important environmental implications.

Lipid extraction is a critical step in the development of biofuels from microalgae. The use of toxic and polluting organic solvents should be reduced and the sustainability of the extraction procedures improved in order to develop an industrial extraction procedure. This could be done by reducing solvent amounts, avoiding use of harmful solvents, or eliminating the solvent at all. Here we describe two new processes to extract hydrocarbons from dried and water-suspended samples of the microalga Botryococcus braunii. The first one is a solvent-based procedure with switchable polarity solvents (SPS), a special class of green solvents easily convertible from a non-ionic form, with a high affinity towards non-polar compounds as B. braunii hydrocarbons, into an ionic salt after the addition of CO2, useful to recover hydrocarbons. The two SPS chosen for the study, based on equimolar mixtures of 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU) and an alcohol (DBU/octanol and DBU/ethanol), were tested for the extraction efficiency of lipids from freeze-dried B. braunii samples and compared with volatile organic solvents extraction. The DBU/octanol system was further evaluated for the extraction of hydrocarbons directly from algal culture samples. DBU/octanol exhibited the highest yields of extracted hydrocarbons from both freeze-dried and liquid algal samples (16 and 8.2%, respectively, against 7.8 and 5.6% with traditional organic solvents). The second procedure here proposed is the thermochemical conversion of algal biomass by using pyrolysis; this process allowed to obtain three valuable fractions, exploitable for energy purpose, fuel production, and soil carbon storage: a volatile fraction (37% on dry biomass weight), a solid fraction called biochar (38%) and, above all, a liquid fraction named bio-oil (25%), almost entirely composed by hydrocarbon-like material, thus directly usable as fuel.

In this paper the expected environmental impacts of the industrial cellulose dissolution with the ionic liquid 1-butyl-3-methylimidazolium chloride (Bmim Cl) were analyzed through a “cradle to gate” Life Cycle Assessment (LCA). In order to weigh up the “greenness” of the process, the analysis was performed through a comparison with the well established environmental friendly N-methyl-morpholine-N-oxide (NMMO)/H2O process. Although dissolution of cellulose in Bmim Cl has not been used for industrial production of cellulose fibers to date, results from LCA suggest that it could be interesting from an environmental point of view since its impacts are similar to those of the NMMO/H2O process. Specifically, the process with Bmim Cl generates a higher environmental load on abiotic resource depletion, emissions of volatile organic compounds and ecotoxicity than the NMMO/H2O process. Conversely it has some environmental advantages with regards to human toxicity. In both cellulose dissolution processes, the major contributions to the environmental impacts come from precursor syntheses. In addition to the comparative analysis of the two cellulose dissolution processes, the paper reports the complete life cycle inventory (LCI) of the two solvents, Bmim Cl and NMMO, and their life cycle impact assessment (LCIA).

The chemoselective addition of tetraallyltin to dialkyl, alkenyl– alkyl, and alkynyl–alkyl ketones can be performed with high yields in N-methyl-N-butylpyrrolidinium trifuoromethansulfonate (MBP-Tf). Other room temperature ionic liquids (RTILs) can also be successfully employed if some sulfonic acid is added. The reaction is very sensitive to the electronic properties of the substrate. Aryl alkyl ketones bearing electron-withdrawing substituents behave like dialkyl ketones and react promptly; on the contrary, electron-rich aryl alkyl ketones react sluggishly, which allows selective competitive allylation of dialkyl substrates to occur. The ionic liquid solvent can be easily recycled, which meets the green chemistry principles of selectivity and reuse of chemicals. NMR spectroscopic data support the formation of tin-triflate catalysts in situ.