Biorefinery: From Biomass to Chemicals and Fuels

Towards Circular Economy

Michele Aresta, Angela Dibenedetto, Franck Dumeignil, Michele Aresta, Angela Dibenedetto, Franck Dumeignil

• Publisher: De Gruyter
• Year: 2021
• eBook ISBN:
  9783110705416
• Topic: Physical Sciences
• Subtopic: Biochemistry

This updated edition presents topical knowledge and technologies for the thermal, chemo- and enzymatic-catalytic conversion of biomass into chemicals, materials and fuels. International experts from academia and industry cover the complete value chain from raw materials into final products. A new focus discusses feedstock, processes and products in potential concepts of future biorefining.

1 Transition from the linear to the circular economy. The role of biorefinery and catalysis

Michele Aresta

IC²R Ltd, Tecnopolis, Valenzano

Angela Dibenedetto

Department of Chemistry, University of Bari, Campus Universitario

Franck Dumeignil

Univ. Lille, UCCS, UMR CNRS

Abstract

The linear economy model is not sustainable for a long time yet, due to the finite natural resources and the negative impact of the gigantic production of waste, typical of the linear model, is producing on natural compartments (atmosphere, water and soil) and climate. The need of shifting to a circular economy closer to nature (use of renewable-C more than fossil-C) is becoming more and more urgent. Circular economy and bioeconomy share the basic concepts of C-recycling and waste reduction. The correct use of renewable carbon brings about the concepts of using biomass and industrial C-recycling. Biorefineries will play a key role in future circular economy.

1.1 The black spots of the linear economy and the disruptive circular economy

The linear economic model has been adopted by humans at increasing intensity since the end of 1700s, favored by the industrial development that has steadily pushed people away from the agriculture-based economy and nature. However, consumerism has dominated our world during the last six decades, based on the false belief that the Earth resources were inexhaustible and enough for all. In such a view, even the timespan of goods became an unnecessary attribute: short-living goods were privileged with respect to long-lasting ones. With the massive introduction of plastics, extraneous to nature, after 1940s, the use once and throw away attitude became more and more popular. After mid-1950, the use of plastics grew exponentially (today we use 360⁺ Mt/y of various plastics) and the throw-away attitude became global, reaching industries, collective services and individuals. With time, plastics have replaced metals, glass and wood, pushing people away from the circularity of nature (nature does not produce waste) and producing huge amounts of wastes that will impact soil, water and biosystems for decades as such materials are extraneous to natural cycles. If in an agriculture-based economy people were educated to thrift and re-use residues (landfilling was not an extended practice, fresh vegetable and garden residues were generally dispersed in soil, bringing back carbon and other nutrients to it, glass and metals were recovered and re-used, wood was used as energy source and ashes were used and finally added to soil), the industrial economy has changed such attitudes. Industry is more intensive than nature: consumption was, thus, encouraged, and maximizing profits at expenses of all other values has been the driver during the last decades.

However, the linear economy (Figure 1.1, top) has produced mountains of waste of all kinds (solid, liquid, gaseous) and damages to fragile ecosystems, even reducing biodiversity. The ever-growing emission of CO₂ is an example, and the carbon capture and disposal (CCS) technology, which was suggested for reducing its atmospheric level, is aligned with the linear economy model: fossil-C is extracted, and CO₂ is produced and disposed.

Figure 1.1: Linear vs circular-economy, and CCS vs CCU. Reprinted by permission from Springer [4] (2021).

1.1.1 Linear vs circular economy

The circular or cyclic economy (bottom part of Figure 1.1) makes more sustainable solutions and long-lasting products available, (Table 1.1) while by-products and residues are recovered and reused for manufacturing new goods. Such practice makes better use of natural resources, while reducing their up-take, and leaving them available for future generations.

Table 1.1:Comparison of linear and circular economy. The table can be read horizontally (through a row) and vertically (through a column).

Linear economy	Pros & cons	Circular economy	Pros cons
Natural resources are continuously extracted	They are used only one time; They are not replenished	Natural resources are extracted and used, but at the end of life, goods are recycled … →	… the extracted materials have several lives
Residues of processes are considered as waste	Goods have a single short life	Residues are recycled	Recycled residues are secondary raw materials
Waste is disposed	Disposal sites are scarce, and leaching of toxic substances pollutes the environment	Residues are not considered waste. Waste is reduced, or even not produced	A cascade of technologies can be exploited for stepwise downgrade use
For disposal, waste needs to be transported to the suited site	Transport of waste may generate a strong environmental impact	Residues may or may not need transportation	Reuse of secondary raw materials can be set up at the same industrial site where they are produced: clustering of processes can avoid long distance transport
Disposal of waste is a cost	In general, there is no benefit from disposal	Secondary raw materials have a value	There is a profit from recycling goods
Disposal sites may leach toxic compounds	Leaching may pollute water, soil and air, reaching plants, animals and humans	A final end-of-lives waste is anyway produced, in general, this can be inert	Finally a non-usable waste is produced. Disposal of such waste has a cost but the amount is much lower

The circular economy can even open the way to new manufacturing activities and generate new jobs. Interestingly, recycling is the extension of a production cycle in which the extraction of raw materials is replaced by the dismantling of the used goods, which in a sense is a kind of mining from a different environment than nature, that may even represent a higher level of complexity. As an example, let us consider recovering all single elements present in a hand phone, which can contain up to some 28 different elements: such matrix [1] is not at all simpler than a natural ore! Just to know, one billion hand phones contain, citing the most abundant, 15 000 t_Cu, 3 000 t_Al, 3 000 t_Fe, 2 000 t_Ni, 1 000 t_Sn, 100 t_Au and 20 t_Pd,In,Ta. As of today, on the Earth, there are more handphones than people. Figure 1.2 correlates value and timespan of goods in a linear or circular economy frame. Single use of natural resources, (A) produces a single time profit for a short-lived product.

Figure 1.2: Value and lifetime of raw materials according to the linear economy (A) and the circular economy (B and C represent the case of recycling to the same function or to lower quality products, respectively). Reprinted by permission from Springer [4] (2021).

Recycling can generate profit n times for the same natural resource that has several lifes (B) or for a cascade of products (C) of decreasing value. Case (B) is relevant to goods like metals that can play the same function n times. Case (C) is relevant to those goods that with recycling do not recover the original properties. This is the case of plastics or paper: plastics used for food packaging will not recover the required properties when recycled and will be used for making goods with lower purity requirements (e.g., packaging); recycled white document paper will be used for making common writing paper, or newspaper paper or cardboards because recycled fibers do not have the resistance and quality of the original material, neither the same whiteness. Water can, in principle, be recycled n times, but reaching the grade of drinking water requires ...

Table of contents

• Title Page
• Copyright
• Contents
• About the Editors
• Contributing Authors
• Abbreviations
• Introduction
• 1 Transition from the linear to the circular economy. The role of biorefinery and catalysis
• 2 Biorefineries of the future
• 3 Terrestrial biomass production
• 4 Production, uses and LCA assessment of aquatic biomass
• 5 Bioconversion and downstream processing in the context of biorefinery: Principles and process examples
• 6 Biomass pretreatment: Separation of cellulose, hemicellulose and lignin. Existing technologies and perspectives
• 7 Catalytic systems for the chemical conversion of lignocellulosic platform molecules into drop-in fuels for transport
• 8 From cellulose to lipids
• 9 New perspectives in lignin valorization: Lignin-derived nanostructures
• 10 Biomass gasification: Gas production and cleaning for diverse applications: CHP and chemical syntheses
• 11 From Syngas to fuels and chemicals: Chemical and biotechnological routes
• 12 Anaerobic digestion of wet biomass. Biogas and biomethane world potential: Opportunities and challenges
• 13 Homogeneously catalyzed conversion of sugars, sugar derivatives and oils to platform and specialty chemicals
• 14 Heterogeneous catalysis applied to the conversion of biogenic substances, platform molecules and oils
• 15 Hybrid catalysis: bridging two worlds for greener chemicals and energy production
• 16 Pickering emulsions and biomass
• 17 Case study on bioplastics
• 18 Assessing the suitability of biomass conversion processes by region: The economic, social and ecological context
• Index