An alternative sustainable fuel, biomass-derived fast pyrolysis oil or “bio-oil”, is coming into the market in Europe. Fast pyrolysis pilot and demonstration plants for fuel applications producing tonnes of bio-oil are in operation, and commercial plants are under design. There will be increasingly larger amounts of bio-oil transportation on water and by land, leading to a need for further specifications and supporting documentation. The properties of bio-oil are different from conventional liquid fuels and, therefore, may need to overcome both technical and marketing hurdles for its acceptability in the fuels market. Multiple material safety data sheets (MSDSs) are currently being used by different producers, but there is a desire to update these as more information becomes available. In order to standardize bio-oil, quality specifications are being adopted. The first bio-oil burner fuel standard in ASTM D7544 was approved in 2010. CEN standardization has been initiated in Europe. In the EU, a new chemical regulation system REACH (Registration, Evaluation and Authorisation of Chemicals) exists. Registration under REACH has to be perfomed if bio-oil is produced or imported into the EU. In the USA and Canada, bio-oil has to be filed under the TSCA (US Toxic Substances Control Act) and DSL (Domestic Substance List), respectively. In this paper, the state of the art on standardization is discussed, and new data for the transportation guidelines is presented. The focus is on flammability and toxicity.

Pore space characteristics of biochars may vary depending on the used raw material and processing technology. Pore structure has significant effects on the water retention properties of biochar amended soils. In this work, several biochars were characterized with three-dimensional imaging and image analysis. X-ray computed microtomography was used to image biochars at resolution of 1.14 µm and the obtained images were analysed for porosity, pore-size distribution, specific surface area and structural anisotropy. In addition, random walk simulations were used to relate structural anisotropy to diffusive transport. Image analysis showed that considerable part of the biochar volume consist of pores in size range relevant to hydrological processes and storage of plant available water. Porosity and pore-size distribution were found to depend on the biochar type and the structural anisotopy analysis showed that used raw material considerably affects the pore characteristics at micrometre scale. Therefore attention should be paid to raw material selection and quality in applications requiring optimized pore structure.

The feasibility of thermochemical biomass conversion technologies can be improved if value-added applications for all fractions can be developed. One of such approaches is the use of liquid by-products from slow pyrolysis and hydrothermal carbonization (HTC) in plant protection. Liquids produced from slow pyrolysis of pine bark, pine forest residues, wheat straw, and willow, and from hydrothermal carbonization of willow, were analyzed in this study. In particular, potential active compounds were analyzed, covering the main volatile, simple organic compounds and numerous phenolic substances. Effectivity tests of the liquids as pest repellent (Arianta arbustorum), herbicide (Brassica rapa), and insecticide (Rhopalosiphum padi) indicated that slow pyrolysis liquid from willow was the most effective pesticide, followed by the liquid from wheat, bark, and forest residues. HTC liquid did not show any pesticidal activity due to low concentration of organic compounds. High content of acetic acid and other carboxylic acids, and the presence of dozens of different phenolic compounds seem to be the main reason for the higher pesticidal activity of willow-derived pyrolysis liquid. Temperature-separated slow pyrolysis liquids proved to be suitable to be used as pesticides. Consequently there is possibility to improve the feasibility of thermochemical biomass conversion technologies remarkably by developing the liquid factions to value-added pesticides.

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Activated carbons (AC) serve as adsorbents in various applications requiring specific functionalities. In this study, the effects of biomass type, pre-carbonization process, and activation method on the properties of ACs were investigated. Chemical (KOH and H3PO4) and physical (CO2) activations were performed on slow pyrolyzed and hydrothermally carbonized (HTC) biochars produced from two feedstocks, willow and Scots pine bark (SPB). In addition, the adsorption capacities of the ACs were tested with two dyes and zinc metal. Distinct differences were found between the biochars and ACs regarding pore size distributions, surface area (238 – 3505 m2 g-1), and surface chemistry. KOH activation produced highly microporous ACs from all biochars, whereas with H3PO4 and CO2 there was also increase in the meso- and macroporosity with the HTC biochars. Adsorption capacity for dyes was dependent on the surface area, while for zinc it depended on AC’s pH. The results provide interesting insights into tailoring ACs for specific applications.