Team:MADRID UCM/Description

Description - 4C_FUELS

As human beings, we have always looked at our surroundings. We are permanently devising new ways to make our reality a better place. We have the ability to realize what is wrong in our world, and aspire to change it for better. Within this page you will find what problems prompted us to work on a project like 4C_Fuels.

INSPIRATION: Our world needs a change!

Never before has humankind had so much control over its environment. In the old days we struggled to survive in a threatening nature, later we learned how to tame it and use it for our own benefit. However, since the industrial revolution, mankind has acquired the ability to dominate over nature. Fueled by the exuberance of new technologies we become capable of harnessing the real power of energy sources like coal or oil.

With this abundant supply of energy, our society rapidly disconnected from the natural course of the world. Combustion fueled our world and we became capable of things never seen before. This way, our economy evolved towards a linear model, where the smart utilization of the resources nature has provided us for centuries, became into the rampant exploitation of any available resource, anywhere and anyway.

However… all of this abundancy was not going to be free. To date, more and more people realize that the way we relate with our environment is not sustainable. We are a society used to extract, use and throw away. Our economic model believes in permanent growth, while the resources we have are limited. In less than a century, we have realized how our newly acquired abilities to cover all of our needs exploiting the environment has actually become one of the biggest threats to our own survival. Emerging global problems like climate change, environmental pollution, or resource depletion are warning us of what we can expect in the future if we don't change the way we relate with the environment.

The problem with linear economy

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Against the way life has always worked, our economy just works in one direction: Forward. We are exploiting resources that eventually become unusable waste.

This system is not sustainable. The accumulation of this waste is generating endless problems: from climate change to the contamination of air and water. What is more, since waste cannot be reused we are forced to permanently extract new resources till their exhaustion.

What will we do one the last droplet of oil has been used? Will we be there to see it or other threats will end this madness before?

Circular economy. The change towards sustainability

We need a change from this linear model to a green and circular economy, and we need it now. We need a society capable of reinventing itself. We need a society capable of readapting to the environment. We need an economy capable of recycling waste back intro products. Luckily this change is possible and it is called Circular economy. This is an ambitious concept that proposes an alternative way of covering our society's needs, while avoiding the problems that the current economic system has. To do so, the circular economy aims to rely on sustainable resources while upgrading waste back into products. The good news is that we have already started working on this.

Renewable energies

During the last decades we have striven to develop more sustainable technologies. Among all of them, renewable energies are the key pillar around which we are building the future for a sustainable world. As we have seen, energy is crucial for our society. The bigger our energy supply is, the faster our society can transform. However renewable energies are still struggling with some problems.

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Great, but not a solution for all sectors

Nowadays the production cost of renewables technologies has become more competitive than fossil energy production. However, their major drawback is the high variability during its generation, forcing us to look for new storage and smart energy distribution technologies.

Despite its rapid evolution, applications with high power consumption and the need of a reliable and constant supply of power usually can not be fully driven by renewable energies.

As an example, global logistics, controlled by ships and planes, still rely on the usage of fuels as energy carriers, since there are no storage technologies with enough efficiency to provide a reliable supply of renewable energy during their operation.

They mostly provide electricity

Renewable energies are great for electricity generation. An outstanding evolution has been seen in terms of efficiency in environmental energy harvesting and conversion.

These results depict a future where it is likely that we could cover all of our energy needs from 100% renewable sources. However they just provide that: energy, and mostly in the form of electricity.

Nowadays only 23% of the global energy consumption is electricity. Then important changes in industrial and public infrastructure have to be achieved for the transition towards a world powered by 100% renewable and clean energy.

We think that renewable energies are great and definitely will have a crucial role in our future, however there is still a long road to drive. What is most important… they can provide us with energy, but… What is about the materials we need to produce physical things?

The Challenge of Sustainable Manufacturing

Our lifestyle requires the production of any kind of goods. Clothing, food, building materials, cosmetics, drugs, devices… The list of products we constantly interact with during our daily life is endless and all of them have to be produced by the industry.

The production of anything requires huge amounts of energy and resources, then it should not come as a surprise that the industry is responsible for almost half of our energy consumption and the main consumer of natural resources.

We all use detergents, fabric, medicines, dissolvents, paints and a loong list of materials that are industrially manufactured. And this will not change in the future.

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Since industry will continue requiring not only energy but also resources and feedstocks to convert into useful products… Could we design a solution that could make it truly sustainable?

The concept of circular economy has been embraced by scientists and engineers from all of the fields, leading to the creation of concepts such as bioeconomy and biorefinery. These are trends that propose alternative ways to exploit the features of the already existing industrial technologies and entangle them with novel biological approaches to achieve an industry that could work under the circular economy principles.

IDEA: Inspired by nature for a sustainable change

A new way of industrial manufacturing

Within our team we have been worried about all the challenges our society is simultaneously facing. However instead of falling into despair we see an opportunity to work on a better world for all. Inspired by the already developed solutions and stimulated by the new sustainable alternatives that year by year are proposed, we want to contribute with our own grain of sand.

After carefully analyzing the global situation, we decided to take a holistic approach in order to achieve a real sustainable way to produce the goods our world needs. With our background in chemical engineering, chemistry and biology, we identified chemical manufacturing as one of the fields where we can generate useful solutions.

We have decided to focus on industrial manufacturing as one of the most relevant participants within the global sustainability paradigm. Since industry will not disappear in the future, we need to look for integrated solutions that could reduce its energy usage, minimize the required resources and reduce the waste generation.

4C_FUELS black and white logo

To do so, in 4C_fuels we have embraced the ideas of circular bioeconomy, studying the natural processes and applying their design for the production of industrial chemical products. Nature has been around for millions of years, mastering the ability to live by the cyclic usage of resources. For nature, nothing is wasted, resources are only transformed from one form into another. This outstanding capacity of nature to thrive almost out of any material and energy source has provided us the inspiration for the development of a truly sustainable chemical manufacturing technology.

How to develop a sustainable solar biomanufacturing technology

The next questions to answer were... How can we minimize energy and resources consumption required during chemical manufacturing? What tools has biolog already evolved to simultaneously achieve these goals?

Photosynthesis is the key process that sustains life on earth. Almost any living being relies directly or indirectly in the fixation of light energy into chemical bonds that creates all the molecules of which living beings are made off. Inspired by nature, 4C_Fuels technology relies on the utilization of the sun as an energy source, while carbon dioxide present in the air is used as feedstock. The higher our ability to directly harness both energy and feedstocks from our environment the more sustainable our process will be. With this approach we could virtually produce almost any carbon-based material out of just air, water and sunlight.

Furthermore, carbon dioxide is the most important greenhouse gas, and can be considered the end-cycle waste of most of the current industrial processes. Our technology aims to upgrade this environmental pollutant back into useful products, helping to bring the carbon cycle back to its natural equilibrium.

We aim to develop a truly sustainable manufacturing platform. To do so, our process must be circular, where manufactured products could become a feedstock after their utilization. This circular process is the key for sustainability and the core of our technology.

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In order to make this cycle move, we will use the most efficient photosynthetic organisms: Cyanobacteria.

These tiny microorganisms have been using the sun's energy for more than 2.8 billion years. Even today, they are responsible for more than 30% of the oxygen we breathe every day. Their high photosynthetic efficiency, together with the knowledge and biotechnological tools currently available for their manipulation, make cyanobacteria perfect candidates for their utilization as a sustainable production platform.

Our Product: n-butanol

n-Butanol is a medium chain alcohol widely used in industry for many different applications. It can be used as an intermediate chemical in the manufacturing of pharmaceuticals, artificial leather, textiles, safety glass, rubbers, cement or perfumes among many others.

Recently n-butanol has been considered as a promising biofuel, since it overcomes the main limitations of bioethanol and biodiesel. First, its energy density is closer to gasoline reaching a 91% when compared to the 60% of ethanol. Secondly, it can be directly used in conventional gasoline engines without the need of further modification. In addition, n-butanol is not hygroscopic, this means that in opposition to ethanol or biodiesel, its tendency to absorb water is low, reducing the corrosion problems associated with other conventional biofuels.

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What’s more, n-butanol can also be used in blends for aviation fuel, since its freezing point is considerably lower (-89 ºC) than standard jet fuel blends. It can also be chemically upgraded via different simple processes towards other compounds that could also be directly used as aviation or even ship fuels.

Would it work?

In order to achieve such an ambitious goal we are not starting from scratch. Actually there is a vast research background in all of the fields we are planning to work in. For decades, the scientific community has been fascinated by the possibility of harnessing the power of biology to solve real world problems. In recent years, photosynthetic microorganisms research has peaked, and nowadays there is a huge collection of strategies and already proven concepts to expand and engineer the native biological features of these organisms.

Then, we are not seeking to discover anything unknown, but to use the available tools and combine all the already existing pieces of knowledge in order to create a real technology never tried before.

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The biorefinery concept is currently fueling a real transformation in the way we produce things. The highly developed technologies and infrastructures that once were utilized for the conversion of fossil resources can be readapted and employed for the obtention and transformation of new bio-based feedstocks.

Biorefinery is a consolidated reality that can support with technical knowledge and a vast range of strategies the development of a truly bio-based industry.

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Synthetic and systems biology provides us with the right tools to adequately understand how living beings work and how to engineer them.

During the last decade advances in bioinformatics and genome edition tools have opened the doors for a complete new age of biological engineering, where almost everything is up to be done.

In addition, despite being almost unexplored during the early beginnings of synthetic biology, phototrophs synthetic biology has developed by leaps and bounds in the last year, expanding the already available toolbox we count with.

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Researchers have been investigating the mechanisms that rule the behavior of microorganisms.

During the last century we have gathered enough information about what kind of organism we should use, what kind of modifications we will require or what kind of strategies we should follow in order to achieve a certain goal.

All of this research has led to important discoveries that demonstrate the feasibility of most of the strategies we are planning to utilize.

Our biggest challenge is simultaneously applying all of them and making them work synchronously.

Committed for a change

After a detailed analysis of the current chemical industry, we have decided to start developing this technology for biofuel production. Then we will start developing a n-Butanol production process.

n-Butanol is a gasoline-like biofuel that can be directly used into any conventional engine without further modification. In addition it overcomes the disadvantages of conventional biofuels such ethanol or biodiesel. It has almost the same energy density as gasoline (91%), it does not require the modification of existing engines and it can be distributed and transported in already existing infrastructure. What’s more, n-butanol is a commodity chemical currently produce from oil that can be used for the production of plastics, lubricants, dissolvents or rubbers among others.

Taking into account all of the above, we can conclude that we have the tools for the development of sustainable solar-driven chemical manufacturing technology with zero-carbon emissions. We will use engineered cyanobacteria to achieve this goal. And this way is how the 4C_Fuels project is born.

4C stands for the acronym of Cyanobacterial Carbon Capture, while Fuels refers to the product we will start producing as a technology proof of concept.

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Inspired by nature, we want to be part of the sustainable change.

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The 4C_Fuels Project

In order to achieve our ambitious goal, our project has structured around 3 main pillars. Metabolic Engineering, Biohybrid nanomaterials and Bioprocesses. Likewise, we have also considered the importance of people to change any aspect of our society.

Metabollic Engineering

The first step for making our technology a reality is the creation of a modified cyanobacteria capable of producing n-butanol and secreting it to the media. In order to achieve this we have firstly performed a deep literature review. After that, we have identified several strategies that we could implement in order to obtain our desired n-butanol super producing strain. These strategies can be grouped into three main aspects: product biosynthesis, enhanced carbon utilization, and product secretion and tolerance improvement. To know more about this, visit our Metabolic Engineering Page. Also, if you want to know about the cloning and procedures we have performed, check the SynBio-Design page.

Likewise, we have decided to overcome the limitations of traditional laboratory strains. In order to develop an industrial process, our strain should be adapted to the industrial needs. Our chassis should be robust and resilient to the harsh conditions usually found in industry. Then, we have decided to work with a newly discovered fast-growing cyanobacteria strain: Synechococcus PCC11801. To know more about, you can visit the Phototrophs SynBio Page.

Bioprocesses. The challenge of industrial scale-up

Major limitations of current phototrophic based processes are derived from the current idea of how microorganisms are used. They are mostly seen as a resource “crop” to grow. MIcroorganisms are just cultured, harvested and transformed through complex industrial processes.

Current phototrophic-based industry is biomass-centered, and that limits its potential. The production of biomass often takes a long time and resources. However, the harvesting and processing steps are the most expensive part, accounting for even 85% of the total production costs.

In 4C_Fuels we want to provide the tools for a paradigm change. What if instead of seeing microorganisms as mere biomass to exploit, we start looking at them as powerful tools that can directly catalyze the reactions we want?

We believe in the possibility of engineering our microorganisms in a way that they behave like living catalysts. This way, the goal of a process would not be to produce as much biomass as possible, but to keep the microorganism converting a desired substrate into an useful product that is secreted.We believe in the possibility of engineering our microorganisms in a way that they behave like living catalysts. This way, the goal of a process would not be to produce as much biomass as possible, but to keep the microorganism converting a desired substrate into an useful product that is secreted.

This way, biomass does not have to necessarily be harvested, and the product can be directly recovered from the culture media, eliminating the need for expensive harvesting processes and even complex biomass reforming steps.

The only costs of the process will be the “maintenance” of the photobiocatalyst and the downstream purification of the final product.

Then, biomass harvesting and processing costs could be eliminated from the equation and a huge amount of resources, energy and money can be saved up in a plea for efficiency. In addition we have engineered our microorganism in order to efficiently work under this idea, but also still being usable under any other kind of conventional industrial process.

However not everything is so easy. We are aware about the challenges that industrial scale up involves. Then we have explored how our technology could be implemented in the real world. To know more, visit our Implementation page.

Photobiocatalyst Development

Another strategy to improve the industrial potential of our technology is to overcome some of the limitations that working with living cells pose. To do so, we have explored the possibility of creating a true photobiocatalytic material, where cells reside secured within a biohybrid material that could be used as a conventional catalyst.

Encapsulating cyanobacteria within a material will not only protect them from threats like pathogens or grazers. But also provide extra advantages.

Has been shown that encapsulated cells can increase their metabolic performance since cell division is limited and carbon is efficiently routed towards metabolite synthesis. Also, encapsulated cells require smaller reactors, as higher biomass concentrations can be achieved without growth inhibition problems. Eventually, encapsulation serves as a biocontainment method to prevent release risks, which are actually one of the biggest concerns when genetically modified organisms are used.

We have explored different strategies for the development of photobiocatalytic materials with promising results. To know more about them, visit our encapsulation page.

Human Practices

From 4C_Fuels we believe in the need to not only be able to develop technology, but also to consider the opinion of society and make it participate in the relevance of our activities. Because of this, our objectives extend beyond biotechnology innovation and development. We believe that sustainability is only possible through a comprehensive change in our relationship with the environment. For this we must take a holistic perspective and involve both the scientific community and industry, as well as society.

To know more about the importance we give to society, scientific communication and social awareness, you can visit our Human Practices page.


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