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Furanic platform chemicals have recently gained renewed attention due to their production capability from bio-based sources including lignocellulosic residues, the reuse of which is highly encouraged by the promotion of a circular economy. Apart from lignins, humins, another side-stream residue generated during the acid-catalysed dehydration of C6 and C5 sugars to produce furanic monomers, is currently receiving attention as a renewable carbon source. Plenty of efforts are seen towards application development for these furanics-based chemicals and materials. Nevertheless, safety oriented data or information on these materials is scarce and this may hinder the market for new products made out of these chemicals/materials. To compliment this, the current study specifically focuses on the fire risk assessment of humins and many other furanic compounds of commercial interest. The study aims at generating safety-oriented data which may assist the user to understand the anticipated risk profiles for making a fair decision on their selection for the desired application.

The development of the so-called bio-economy, replacing « black gold » by « green gold » towards industrial ecology as well as the promotion of the circular economy lead to consider wastes and biomass residues of different sources as new and valuable feedstocks. This global context requires a new paradigm in the way we should tackle the issue of material and process safety in advanced biorefineries. This was recently debated in a wokshop organized by DG Research [1] where safety consideration was pointed out as deserving dedicated research in this area. In addition, adequate safety management strategy implemented at early design stage was also perceived as a contributing factor of sustainability and societal acceptance of industry. Based on recently completed or on-going projects like Imidazolium or Evalbioraf (SAS Pivert), HUGS, ALFA-BIRD, ZELCOR, GREENLAND, FLEDGED (EU FP7 & H2020 programmes) or CORABIO (CR Picardy), the presentation will examplify key issues that needs to be considered towards proactive material hazard characterization or process safety in this sector. Final goal of the presentation is ultimately to explain the attendees how to move from conventional risk analysis and simple compliance to existing safety focused regulations towards advanced integration of safety management as a key and measurable sustainability aspect in the context of biorefining. Among material-focused safety issues, the cases of alternative solvents or green solvents like « ionic liquids » (Fig. 1a) [2] or deep eutectic solvents (Fig. 1b) or biofuels will be pointed out to show about ignored or underscored safety issues or on misleading data regarding their fire behaviour at large scale (fuel ethanol). The importance of revisiting self-heating behaviour (see Fig.2) and other safety related issues all along innovative value chains with biobased feedstock [3] will also be outlined with an insight on biobased residues like biomass materials issuing from phytoremediation of polluted soils. The emerging interest on furan derivatives since new biobased routes of productions were shown promising will also been commented in terms of new needs to dig in the relating safety issues. Even more rarely investigated in recent research [4/5], safety aspects mostly addressing the process side (preatreatment, conversion, downprocessing, emission abatement) will be the latter part of the presentation covering key aspects of biorefining as : a) biological conversion processes and « accidental » biological risks, b) upstream and downstream flexibility demand versus safety , c) process intensification and inherently safer design (ISD) potentially antagonistic aspects [6], d) safety issues pertaining to process water, thermal and carbon streams recycling or to process integration, e) hazards pertaining to zero waste and energy self-sufficient targets), f) Corrosive environment problems as compared to classical refineries. This latter issue at frontier of product and process safety will also be debated at light of existing new hazardous property « corrosive to metal » recently introduced in CLP Regulation 1272/2008/EC and findings from the ECORBIO project. Eventually, the interest to link the safety approach and the evaluation of the environmental impacts of biobased processes will be also discussed.

Production of new carbon-based building blocks from lignocellulosic biomass residues is progressively replacing share of petroleum based chemicals in transportation fuel and commodity polymers. Chemicals such as 5-hydroxymethylfurfural (HMF) and furfural can be produced by depolymerisation of C6-sugars (eg. glucose) and C5-sugars (eg. xylose), via acid catalysed dehydration (ACD). This can be further converted into various furanic derivatives (FD) such as 2,5-furandicarboxylic acid (FDCA) or furfuryl alcohol (FA), which are well-known precursors of bio-based polymers. Considering the diversity of existing and potential FD structures and their varying phys-chem properties (Fig a), we may anticipate several types of risks that may trigger during their synthesis and targeted applications and may have highly varying profiles. Except for a few well-known FD (furan, furfural, furfuryl alcohol, hydroxymethylfurfural etc), others have been paid much less attention so far, with no specific information on their hazardous profile in internationally derived haz-mat classification systems such as GHS (CLP in the EU) and the UN TDG Model Regulations for transport of dangerous goods. Haz-mat classifications are one of the preliminary requirements for all chemicals for their appropriate classification, labelling, packaging and safe transportation. However, these classifications do not necessarily provide information about the extent of risk involved when the chemical is used in any specific application. The risk involved may also depend on thermal stability of the compound, speed of combustion, chemical incompatibility issues, type of surrounding environment, conventional methods of storage and disposal, safety training to the employees, etc., These are some of the governing factors that are out of the scope of any haz-mat classification system and they can only be addressed by application based testing. Therefore, to address these existing discrepancies and to meet the new market requirements, the current study as part of the HUGS project focuses on examining the safety profile of existing and some newly synthesized FD, and their byproducts such as humins & levulinic acid. Specific focus is given on learning their thermal stability, flammability or combustion behavior during fire scenarios via various testing procedures. Thus, the study aims at defining specific trends of physico-chemical properties for the family of FD for the selection of best-suitable compound based on its functionality and applications.

The European Union?s approach of replacing progressively fossil sources by other renewable sources to support the transportation fuel and production of commodity polymers is one significant driver of the bio-economy. Today?s research is focusing more on faster and effective sustainable biomass conversion techniques with successful attempts resulting in producing new versatile carbon-based building blocks from lignocellulosic biomass residues. Chemicals such as 5-hydroxymethylfurfural (HMF) and furfural can be produced by the dehydration of cellulosic and hemicellulosic fractions to extract C5 and C6 sugars which can be further converted into various furanic derivatives (FD) such as 2,5-furandicarboxylic acid (FDCA) or furfuryl alcohol (FA), which are well-known precursors of bio-based polymers [1]?[3]. Owing to the wide variety of phys-chem properties, and wide diversity of existing and potential FD structures (fig.1), one can anticipate risk profiles may be triggered and can highly vary during their synthesis and targeted applications. First order about hazards pertaining to marketed chemicals can be obtained from various haz-mat classification systems as those derived internationally from the (GHS) (like CLP regulation in the EU) and from the UN TDG Model Regulations for the transport of dangerous goods [4], [5]. However, except for a few well known FD (such as furan, furfural, furfuryl alcohol, hydroxymethylfurfural etc), these regulations have limited interest as in most cases, no harmonized classification or UN number have been given to FD. Moreover, access to Material Safety Data Sheets (MSDS) where hazard rating must be done as a duty of the supplier are only available when the FD of interest has already been put on the market. Besides, use of conventions in those haz-mat classifications leads very often to misleading messages when the threshold value for a given hazard is not reached. For instance, qualifying a compound as ?non-flammable? is misleading to some extent. Similar to most ionic liquids, many FD (furfural FP 60 0C) does not enter the class of flammable liquids, due to their flash point (FP) position compared to limits defined by regulatory frameworks (eg. flammable substances have a flash point ?60 °C in the CLP) [6]. Depending on the context of use, compounds that are not identified as ?dangerous? may still induce flammable, corrosive, oxidative, toxic and eco-toxic issues [7], meaning that these classifications are set by pure convention (fig.2). In addition, thermal stability, speed of combustion, type of surrounding environment, conventional methods of storage and disposal, safety training to the employees, etc., are some of the governing factors that have to be considered in further evaluation of risk at use beyond haz-mat classification. Growing research, innovation in the field of biomass conversion processes is leading to synthesis of brand new FD which raise the need of providing holistic safety assessment. To meet the new market requirements and to resolve some of the above mentioned discrepancies, there is a need for careful examination of the potential risks associated in the family of FD. The current study is part of the HUGS project [8] and focuses on examining the safety profile of existing and some newly synthesized FD, while safety aspects of humins & and other derivatives like levulenic acid will also be taken into account. Specific focus is given on learning their thermal stability, flammability, or combustion behavior during fire scenarios, via fire propagation apparatus & flash point tests. The study aims at identifying and defining specific trends of physico-chemical properties of the family of FD thus developing knowledge to choose the best-suitable compound based on its functionality and applications while integrating economics and sustainability.