Sustainable Development Goal 7: Biofuel Production from Biomass Conversion

Dear Colleagues,

It is our pleasure to announce a new Special Issue, ‘Sustainable Development Goal 7: Biofuel Production From Biomass Conversion’, for the journal Sustainability. Biomasses are among the biogenic resources with the greatest potential to contribute to energy transition, but they also constitute a highly heterogeneous set of materials that require transformations and standardizations to become biofuels that can be used in common energy valorization processes. This Special Issue focuses precisely on the aspects of the processes, uses, and sustainability of the transformation of raw and uninteresting biomasses into homogeneous and energetically valid biofuels.

According to the most up-to-date statistics, the share of fossil fuels in the energy consumption mix is predominant in all countries in the world apart from Sweden, Brazil, and Norway (which have 53.89%, 50.33%, and 72.09% of renewables used as a portion of their primary energy consumption, respectively). Although on a global scale, and much more evidently on a European scale, energy policies are pushing towards a reduction in the consumption of fossil fuels, the set goals are still far away. A pivotal role in reversing energy consumption patterns can be assumed by the biomasses and the biofuels derived from them. Biomass and biofuels are considered to be crucial for energy, but also for environmental policies, given their ability to avoid the consumption of fossil fuels, reduce greenhouse gas emissions, and increase (for some conversion systems) carbon storage capacity. The term “biomass” can be used to identify different meanings, from ecological (or, more correctly, living biomass) to specifically energetic significance. Thus, a biomass is any product, residue, or waste of a biogenic nature that derives directly or indirectly from the photosynthetic phenomena of carbon dioxide organization due to solar radiation. By their nature, biomasses have both negative and positive characteristics due to their relevant heterogeneity, variable moisture content, and consequent low energy density. However, they are also considered pervasive and readily accessible, offering a multitude of applications and valorizations. Being a biogenic resource, they are included in a neutral carbon balance (if there is no change in land use). In the course of modern history, numerous approaches have been developed to derive energy from biomass in the form of heat and electricity. More recently, attention has been paid to the formation of biofuels from biomass, whether solid, liquid or gaseous. From a technical perspective, there are four practicable paths to create standardized biofuels from heterogeneous biomass with little energy density: physical–mechanical, thermochemical, biochemical, and chemical–physical processes. The former have the specific purpose of generating solid biofuels such as pellets, wood chips, and briquettes, and largely respond to the standardization protocols established by ISO 17225. Among the notable thermochemical processes, pyrolysis and gasification are used to generate solid (charcoal), liquid (bio-oils), and gaseous (syngas) biofuels. Biochemical processes based on the use of organisms, microorganisms, and enzymes are applied to generate liquidous and gaseous biofuels. Finally, chemical–physical processes are mainly used to produce liquid biofuels such as biodiesel, green diesel, and drop-in type HVO.

The aim of this Special Issue is to encourage the publication of experimental, computational, and theoretical research related to the sustainability of biomass conversion systems and the production of biofuels for energy use. We welcome original scientific articles, case studies, systematic reviews, critical reviews, overviews, and meta-analyses. Subject areas of interest for submission are as follows:

• Environmental sustainability assessments on the renewable energy and biofuels sector.
• LCA applied to biofuel generation and use.
• Chemical, physical, and energetic evaluation of biofuels and biomass.
• Physical, chemical, biochemical, and thermal processes for biomass exploitation.
• Biomass and biofuel production.

The aim of the Special Issue can be directly related to several of the subject areas of the journal Sustainability, such as those related to energy, the measurement of environmental sustainability, the impact of products and production systems, and the calculation of carbon and environmental footprints, but also indirectly to aspects of economic and social sustainability that are always linked to the value chains of biofuel production.

We invite original research articles, critical reviews, and the other forms of scientific literature mentioned above on topics related (but not limited) to the following:

• Applications of thermochemical processes (pyrolysis, gasification, carbonization, and hydrothermal carbonization).
• Applications of biochemical processes (anaerobic digestion, fermentation, and enzymes).
• Applications of chemical–physical processes (transesterification, hydrogenation, hydrocracking, etc.).
• NIRS applied to non-destructive characterization.
• Biomasses and biofuel quality parameter assessments.
• Solid, liquid, and gaseous biofuels’ sustainable production and utilization.
• Environmental impact assessments of biofuels along the whole production chain.

Prof. Dr. Alessio Ilari
Dr. Elena Leoni
Guest Editors

Manuscript Submission Information

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• biofuel
• biomasses
• renewable sources
• energy conversion
• life cycle assessment
• sustainability
• environmental impact
• near-infrared spectroscopy
• thermochemical processes
• biochemical processes
• chemical–physical processes
• novel fuels
• drop-in biofuels