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Since fuel is made up of different molecule chains, my question is what is the reason we cannot create the same molecule structure and be able to reproduce the same structure in a lab so we don't have to run out?

I understand there's way more to this and it's not as simple as I make it seem but that's why I am asking: what are the challenges in doing something like this? Can we not make the same structure?

Also as a side note, do fuels have oxygen molecules already inside the chain or do they not receive these molecules until the mixing of the oxygen using valves?

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    Does this belong here or the chemistry board?
    – race fever
    Apr 23, 2016 at 2:50
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    Oil can be produced using varying methods, that's not the problem. The problem is that making it in a lab would cost much more than drilling it up from the ground, especially in the quantities we are using.
    – vsz
    Apr 23, 2016 at 19:34
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    The energy, technically. Apr 24, 2016 at 8:59
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    Create it from what? Thin air? Apr 24, 2016 at 17:01
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    Energy is the most important bit. It's also a cheap source of hydrogen. It's quite easy to make oil from coal, but that's only useful in limited scenarios. It would be technically possible to capture carbon dioxide and use water to manufacture synthetic oil, but that's 1) a huge net energy loss and 2) much more expensive than just drilling the stuff. But don't worry, when oil starts to run out (not going to happen any time soon), as it gets more expensive alternatives will spring up rather fast :)
    – Luaan
    Apr 24, 2016 at 21:51

11 Answers 11

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Oil as it comes out of the ground is a mixture of hydrocarbon compounds that are the remains of deposits of algae and microscopic animals, also called phytoplankton and zooplankton.

Scientists have already created synthetic fossil fuels.

The efforts

1. There is currently a $300 million dollar (actually much larger) effort in San Diego, California by a company called Synthetic Genomics and Exxon Mobil to use algae to make oil. The lipids, a form of fat, in the algae are a major component of crude oil.

Excerpt from: http://www.sandiegouniontribune.com/news/2009/jul/15/1n15algae001356-deal-blooms-algae-biofuel-research/?uniontrib

A San Diego biotechnology company led by genomics pioneer J. Craig Venter has landed a deal with Exxon Mobil that could include more than $300 million in funding to develop biofuels from algae.

Venter, best known for his role in sequencing the human genome, said yesterday that his company Synthetic Genomics is planning a local greenhouse and test facility to study thousands of strains of algae from around the globe.

The eventual aim is to engineer algae that would use energy from the sun to convert carbon dioxide into oils and hydrocarbons in large quantities – a feat that would be prohibitively expensive with naturally occurring algae.

As of now the above project has failed and is back to the drawing board.

Excerpt from: https://www.technologyreview.com/s/515041/exxon-takes-algae-fuel-back-to-the-drawing-board/

Those efforts don’t seem to have cracked the code for cheap algae fuels. In a new agreement between the companies, Exxon is sending Synthetic Genomics back to the lab to do more basic science. It will focus now on its namesake technology–synthetic genomics, a relatively new science that involves making large changes to genomes, even to the point of building whole new ones. The goal remains the same: “to develop strains which reproduce quickly, produce a high proportion of lipids and effectively withstand environmental and operational conditions.”

2. Chevron has a joint effort with a company called Catchlight Energy to use algae as a raw material for making petroleum. Chevron has also partnered with Weyerhaueser Co, one of the worlds largest forest-products companies to begin using wood waste. Ligno-cellulose found in wood is also a component of petroleum.

Excerpt from: http://investor.chevron.com/phoenix.zhtml?c=130102&p=irol-newsArticle&ID=984280&highlight=

Chevron Corporation (NYSE: CVX) and Weyerhaeuser Company (NYSE: WY) today announced a letter of intent (LOI) to jointly assess the feasibility of commercializing the production of biofuels from cellulose-based sources.

The companies will focus on researching and developing technology that can transform wood fiber and other nonfood sources of cellulose into economical, clean-burning biofuels for cars and trucks. Feedstock options include a wide range of materials from Weyerhaeuser's existing forest and mill system and cellulosic crops planted on Weyerhaeuser's managed forest plantations.

In nature, the only reason it takes millions of years for these organic materials to change to oil and natural gas is that it takes that long for it to be buried to a depth where the temperature and pressure are high enough to convert these materials to petroleum.

In reality, the time it takes to convert these from algae to oil may be less than a few hundred years, and that again is because of the slow change in temperature and pressure in a geologic setting.

Oil has been generated and found in sedimentary deposits as young as 1000 years old, so it does not require millions of years. In an industrial setting this all can be done in a matter of hours or days.

Challenge

In the lab, organic material can be heated (~320C) up in an inert atmosphere with water under pressure (~150 atm) to simulate the natural processes that take millions of years but take only a matter of days in the lab. This is due to simple thermodynamics, thousands of years at 100 C or a few days at 320C give similar products.

This technique is used to analyse whether immature rocks, if they had been buried more deeply, could produce crude oil. So it can be used as a tool to search for oil reservoirs.

It is not economically viable to do it on a large scale since so much energy has to be put into the system.

Side thing

As for this point,

The chemical composition of gasoline does have oxygen in it such as ethanol blended gasoline or methanol blended gasoline but it can't behave as oxygen. So it needs oxygen from outside, namely air. When these two components are ignited it combusts and releases energy. Basic chemistry.

Here is the reaction happening inside a cylinder during the combustion stroke.

2C8H18 + 25O2 → 16CO2 + 18H2O

Hope this helps!

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    This is really great. Good info and solid references. Well done.
    – JPhi1618
    Apr 23, 2016 at 3:38
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    Indeed. It's next level. +1 Apr 23, 2016 at 12:37
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    Impressive detail, but it really is just all about the energy. Given enough energy chemists can make anything.
    – nekomatic
    Apr 23, 2016 at 20:20
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    @LostPecti: You're mixing two things. One is making fuel out of dead organisms. This is how heat, pressure, and lack of oxygen have been generating fuel out of a large variety of organisms over the millenia. We can speed this up in the lab (more heat, more pressure), but we need a way to quickly mass-produce dead organisms to input in the process. The other is making live plants use photosynthesis to produce fuel instead of leaves and wood. Plants don't do that naturally, you'll have to genetically engineer them to change their biology. Apr 24, 2016 at 10:02
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    @saurabh64 Octane (like all alkanes) does not contain oxygen. The formula for octane is C8H18 (the only constituent elements are carbon and hydrogen). Gasoline is a blend of a variety of chemicals, including octane; some of those other chemicals do contain oxygen. Some gasoline blends include ethanol (ethyl alcohol). Alcohols include a hydroxyl radical (OH) which is oxygen and hydrogen. So, gasoline may contain oxygen, but it is contained in secondary components and additives, not the primary hydrocarbon components, which as their name suggests are compounds of just hydrogen and carbon.
    – Anthony X
    Apr 24, 2016 at 15:45
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What's in fossil fuel that we can't reproduce is energy.

We've been making synthetic fossil fuels in one form or another for about two centuries: town gas (a methane substitute), synthetic gasoline, biodiesel, and so on. With the exception of biodiesel, however, all of these take considerable energy to produce, whereas fossil fuels can simply be pumped out of the ground.

Because of this, synthetics have only been used when natural fossil fuels were unavailable. Town gas was used prior to the discovery of the North Sea oil fields and the development of techniques for transporting natural gas, while synthetic gasoline was used by Germany during World War II, when it didn't have access to the natural version.

Current efforts to make synthetic fuels are centered around using plants or algae, so that free energy from the sun can be used.

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    A minor nitpick: biodiesel also takes loads of energy to produce, but we can outsource most of that to the plants being grown to supply the raw materials - "cheap" solar power. Those plants are very inefficient in their conversion and quite demanding on land area (and soil quality, until we get those algae going :P), but they're quite simple to care for, and require little capital investment. Of course, depleting soil as a cure for depleting fossil fuels isn't exactly the brightest idea - at the very least, we'll need to get a lot better at recycling the waste products.
    – Luaan
    Apr 24, 2016 at 22:07
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The other answers are right, technically. As they say, what's in it is energy, or hydrocarbons, or whatever you want to call them. Burnable stuff. Unfortunately, the first two laws of thermodynamics tell us that artificially putting energy into a substance would take more energy than you'd get out, so it couldn't possibly be profitable [which, as an aside, is why hydrogen fuel cells are just batteries, not power sources].

But plants put energy into things for us, from the sun, for free, naturally. So people have made them into biofuels.

But most of us don't run our cars on biofuels. So that doesn't really answer the implied question, does it? Which is, why are we still getting it from the ground?

What's missing is volume.

A hundred years ago, there was enough molasses being manufactured in one vat of one factory in Boston to create a tidal wave large enough to kill 21 people:

Boston Molasses Disaster

Imagine how incredibly much more corn syrup there must be nowadays, now that it's in freaking everything.

Something similar happened at around the same time, with the London Beer Flood drowning eight people, and destroying two homes.

Imagine how much more we must drink nowadays! Unimaginable amounts. Add to that beer, all the tea, soda, bottled water, milk, etc.

Now imagine for a moment that these substances were not made almost entirely of water. That they were made only of their concentrated syrup, but in the same volume. Would it be possible to produce any of these artificially, in that volume? No. We're at about our production limits already.

Even with watering down, let's look at the prices. March 2016, average US prices for a gallon of:

$1.96 Unleaded regular.
$2.20 Kool-Aid, Lemonade from concentrate:
$2.37 Soda (2l/$1.25 budget deal)
$3.16 Milk
$3.60 Hot Chocolate from powder (am drinking this now!)
$10.50 Homebrew beer from a kit.

All of these things, even watered down about 90%, even with me cherry-picking the cheapest prices I could find in a quick search, are more expensive than our fuel.

And yet, gasoline production utterly dwarfs them, even all added together.

Obligatory XKCD image: Gasoline volumes are insane

[[Side note: a puddle the size of these pipes, about 1mm deep, is how much each person uses up each day on average.]]

Volume is the secret sauce. Volume is why petroleum/gasoline is the only liquid other than water that gets piped around the country rather than trucked. And volume is why we cannot produce car fuel artificially.

And while efforts are being made, these will mostly end up being used in power stations, generators, airline fuel, and home heating, as electric cars will make the internal combustion engine obsolete in a few years anyway.

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    Best response, formatting, look and feel....lol. Great answer. Thanks for contributing and welcome to the site! Cheers. Apr 23, 2016 at 20:27
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    Yes. People complain about gas prices, but I think few really appreciate just how cheap and compact a source of energy it really is. Apr 24, 2016 at 4:32
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They can

They have strung together various polymer chains in the lab and their even hydrocarbons. The University of California Berkeley is doing it now. It's not really a question of it being done. It's the cost of doing it. Right now, it's not financially feasible to be competitive in the current market. The other methods of pulling dead dinosaurs out of the ground is just cheaper.

Here is a link where UC Berkeley used the E. Coli bacteria to help produce a gasoline replacement.

Being excited about biofuels might be misplaced though. The Nobel Prize winning chemist Paul Crutzen published finding that stated nitrous oxide emissions created during the production of biofuels made them contribute more to global warming than current fuel solutions.

So, before we get all excited about lab produced fuels from biological waste we're going to have to find a better process to convert the biological matter or look elsewhere for the solution.

Currently, there are biofuels that are making it into the market and getting mixed in with our standard fuel. One of them, ethanol, is derived from corn. The unintended consequence with that one is that corn growers in central and South America are selling their corn to fuel producers and have driven up the price of corn so much that people are actually starving because their carbohydrate base they rely upon as a food source is more valuable in the gas tank of a car. So, there's that.

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    It isn't just South America where food prices have gone up, it's here in North America as well. Even though fuel prices have come down, food prices have not, which is a direct reflection on this. Apr 23, 2016 at 12:07
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Petroleum from the ground is a mix of different molecules, but have in common the fact that they were created with energy from the sun. So, knowing what the molecule(s) looks like, we can assemble the ingredients in the proper lab equipment, add heat (energy) and outcomes our gasoline. However, the energy cost of doing this (because of the laws of thermodynamics) exceeds the energy contained in the product, thereby making the process a net loss of energy. That's why we do not make our own fossil fuel.

It's exactly the same reason that the "hydrogen generators" marketed as an add-on to automobiles years ago to improve mileage, cannot do that. The energy required from the cars electrical system, however small, always exceeds the energy produced, even smaller.

And to add insult to injury, the energy released when we combine oxygen with our petroleum results in a re-arrangement of the different elements in the molecules. One of the byproducts is carbon dioxide. We are not fond of that either even though plants will eventually, with sunlight, turn it back into a carbon based product which we can then burn again, if we choose.

The quest for "renewable" energy is then a search to find some thing which will capture the sun's energy quickly (in a single day) and store it in a way that allows it to be extracted in a controlled way. We are asking for "overnight" oil. Photocells and turbines work well - when they work--not always when we need the energy.

Now you get the picture. We cannot make fuel - even the coveted Hydrogen - without expending more energy than we will produce.

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  • For bonus points, the most economical way of producing hydrogen today is... petroleum. Congratulations on replacing our petroleum dependency with a petroleum dependency with additional complications! :P That said, both synthetic gasoline and hydrogen might be interesting mediums for energy storage - provided we get the energy somewhere renewable. Or nuclear, whatever floats your boat.
    – Luaan
    Apr 24, 2016 at 22:14
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Nothing.

Everything in fossil fuels currently in use can be mass produced.

It would simply cost more than pumping it out of the ground.

Fossil fuels are merely a cheap, but inefficient, way to store energy.

If the world had cheap, efficient sources of energy, it would not likely waste any effort on storing that energy as petrochemicals. We'd have directly electrically powered vehicles, or something more efficient like hydrogen fuel cells.

So in the end, the answer to your question is.. Money.

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    Inefficient, eh? The energy density of gasoline is 46.4 MJ/kg. To compare, a lithium-ion battery is 1.8 (25 times less). Natural gas is a little better, at 55.5, but more dangerous to store. To get much better, you need to go nuclear - like Plutonium at 2.2 million MJ/kg, or Uranium (81 million). Now THAT is efficient. Apr 26, 2016 at 15:02
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While there are some great answers, the simplest chemistry-based answer is that it is almost impossible to efficiently form carbon-carbon bonds other than with biological systems. We can make H2 by electrolysis of water, and we can break down (crack) biological hydrocarbons or polymeric carbon (coal) to make pre-existing biofuels more useful, but as yet, photosynthesis can't be beat for moving carbon from CO2 to fuel.

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  • Yeah, we've only had a simple way of doing so since the 1913 or so :P World War II Germany run on synthetic gasoline and lubricants for quite a while. Plants are very inefficient in capturing solar energy in hydrocarbons - the only reason they're important at all is that there's just so many of them, and that they're so cheap to spread. Of course, the concentration of carbon dioxide in the atmosphere is tiny, which complicates the process - you can't concentrate production much. A better approach might be capturing the carbon dioxide after combustion, rather than letting it mix with air.
    – Luaan
    Apr 24, 2016 at 22:21
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There are some good answers here to the off-topic question. Some people refer to problems of "cost", some to problems of "energy". Pay attention though: these are the same thing really. You have to do some basic accounting to determine if the business is viable. The most basic accounting is the "energy-in" - "energy-out" balance. If you are making a hydrocarbon in the lab, there will always be a loss, due to the principle of conservation of energy, and the unfortunate fact that we can't make a device that is 100% efficient. You will never break even.

There might well be more efficient ways of storing and delivering your lab's energy source than in a hydrocarbon chain.

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Bear in mind that we use petrochemicals (carbon compounds extracted or released from the ground) for two distinctly different purposes: fuel and raw material for manufacture of all sorts of things. To remove our dependence on petrochemicals, we would have to address both uses.

To replace petrochemicals as an energy source, in some cases it would be better to find other ways to store and release energy - batteries recharged by wind turbines or solar arrays, for example. But most fossil fuel alternatives have issues with convenience, capacity (specific energy by weight or volume), power density (again by weight or volume), safety of handling/storage (think hydrogen), NIMBY (think wind farms), etc.. It's just so easy to fill a tank with gasoline, diesel, jet fuel, etc., fire up an engine and go.. not to mention relatively light weight and compact. So maybe for some applications like aircraft, it may be more feasible to continue powering them in the current manner (accepting all the drawbacks), but consider alternative sources than petroleum - hence biofuels.

To replace petrochemicals as a manufacturing raw material, you'd have to consider all the things our modern world derives from them. Plastics, solvents, dyes, lubricants, adhesives, and so on. All of the interesting molecules extracted from crude oil (and it can be a long list) would have to be produced by some other means.

In either case, these petrochemical equivalents would each have to be produced on a vast scale. We as a global community burn a lot of fuel just getting around, and we make all sorts of things (also on a vast scale) from petroleum. It comes down to three big things:

  1. Figure out how to make our substitute (say, octane or some other hydrocarbon) by chemical and/or biological processes from something we didn't extract from the ground (e.g. carbon dioxide and water). There is ongoing research into this with interesting results emerging all the time.

  2. Scale up the processes to a level which meets the demand. For one thing, it will take massive investment; who will put up the money? For another: if you're going to put carbon dioxide and water into a process and get hydrocarbons out, you're going to have to add energy, which has to come from somewhere. This may be a major sticking point for synthesizing petrochemical equivalents on any worthwhile scale. Do we build vast solar/wind farms? What will that do to the global landscape? Do we build more nuclear?

  3. Make it economically viable. People may be persuaded to pay a small premium for a non-petro-sourced fuel or consumer product, but there will be a limit. Can a non-petro process even come close to the economics of today's wells and refineries?

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  • Crude oil is just different length hydrocarbon chains. Practically any hydrocarbon can be produced from any other hydrocarbon in industrial processes utilizing hydrogen. Hydrogen can be obtained from natural gas or from electrolysis of water. The majority of oil is refined to gasoline, diesel, jet fuel, etc. Once you address the scales of transportation uses, you already have the scale needed for every single other use of oil. Plastic? Solvents? Dyes? Lubricants? Adhesives? No problem if you have the scale for transportation uses.
    – juhist
    Oct 21, 2018 at 17:34
  • @juhist Refinery processes are predominantly distillation and cracking; distillation to isolate specific chemicals e.g. octane from an input stock, and cracking - breaking longer chain molecules into shorter/smaller molecules. They don't "cook up" molecules like the heptane and octane used in cars or the hydrocarbons comprising diesel or jet fuel. To meet the current demand for such products would require huge investments in research to optimize the necessary processes for economy at industrial scale, as well as huge investments to actually implement them. And again: from where the energy?
    – Anthony X
    Oct 21, 2018 at 18:14
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Taking the real question to be 'Why don't we make fuel from scratch instead of pumping it out of the ground?', I'd have to say the core issue is energy - more specifically, conservation of energy. Fuels are NOT energy sources - they are energy storage mechanisms (like batteries). Whatever energy one gets out of fuel combustion, one must first gather to create the fuel in the first place. It is a zero-sum game. What makes fossil fuels different is that Nature spent hundreds of millions of years collecting solar energy into organic storage (i.e plants) and sequestering it in the ground for us to find.

And now we're consuming that resource a million times faster than it took to accumulate. We're living on borrowed time, people!

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We can mass-produce synthetic fuels. It has been done by Germany in World War 2 (albeit from fossil sources). What you need is carbon and hydrogen.

Unfortunately, carbon is typically in the nature in the form of carbon dioxide (and fossil fuels, but they were specifically excluded in the question) and hydrogen in the form of water. To separate hydrogen and carbon from these, you need energy. The carbon and hydrogen can trivially be combined into hydrocarbons in chemical reactions.

Fortunately, energy is a plentiful resource on planet Earth. There are two main ways to produce energy. One is to harvest the energy of the sun, either directly or indirectly. Indirect means include wind, hydropower, and even renewable biofuels and (god forbid!) fossil fuels. Direct means photovoltaics or concentrating solar-thermal power. The direct ways allow many many orders of magnitude greater energy use than what is used today, for billions of years.

The other main way to produce energy is nuclear, which is also a plentiful resource. There is enough U-238 in the seawater and ordinary granite rock that we can sustain the current energy usage levels for billions of years, until the sun will enlarge and destroy us.

The main issue is cost. The facilities to manufacture synthetic fuels are expensive, but in a pinch will work, as Germany during the World War 2 showed us. The facilities to electrolyse hydrogen from water aren't cheap either. Carbon dioxide extraction from atmosphere also costs some. Furthermore, energy production also has its costs, but however, the cost of solar is rapidly reducing and may be the energy production choice of tomorrow's cleaner world.

It isn't so far-away dream to produce synthetic fuels. Today, Neste produces NExBTL which is essentially diesel produced from bio-sources that is equivalent to regular diesel and requires absolutely no car modifications. Today, there is a plan to construct a biorefinery to produce biogasoline in Finland. So, certainly the conversion of carbon and hydrogen to synthetic fuels isn't the issue: both biodiesel and biogasoline can be produced.

The remaining issues are:

  • Cost of energy, which will be a non-issue in a few decades due to rapidly reducing solar cell costs. Energy already occasionally has a negative cost in Germany due to the large-scale intermittent renewable energy production. What we need to do is to extend the duration of time where energy has a negative cost by installing even more intermittent renewables.
  • Cost of capturing carbon dioxide. Initially, it will be captured from industrial and power production sources, but eventually, in the clean world of tomorrow, it has to be separated from air, because there will be no CO2 sources (except mobile sources, for which capture is difficult).
  • Cost of electrolysis of water. Today, it's cheaper to produce hydrogen from natural gas than to electrolyse it. However, tomorrow, the costs may be different, partially due to falling energy costs.
  • The big oilfields that haven't been depleted and that can be used to produce oil for decades to come at minimal marginal cost. The price of fossil oil will settle at the level where supply and demand are in balance. This means fossil oil will be used for a long long time, unless government forbids its use or places a tax on its use.

What remains to be seen is to what extent the synthetic fuels are needed. Electric car has certainly shown its viability, so it may be the case these synthetic fuels will be used by aviation, not by road transport.

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