James Tour 0:03
Okay, so my name is James Tour. And I'm going to be talking to you a little bit about, in this climate action section, about carbon and beyond. And so what we've been able to do is we prepare something called Flash Graphene. And what that involves is we take any carbon source that is a solid, any carbon source, we put it between two electrodes, and we put a voltage and run a current through it, it's not a plasma, it's got a real current going through it. And everything in here will heat up. And it heats to over 3,000 Kelvin, and in less than five milliseconds, and then it cools very rapidly. So it’s at about 105 Kelvin per second, cools it about 104 Kelvin per second, such that after this, this little reaction that's in here, so this is just a quartz tube, after this little reaction, the quartz tube is only mildly warm to the touch and that's because all of the energy goes into this material. It breaks all the carbon bonds and reassembles as the most thermodynamically most stable material, which is graphene, and the hetero atoms come subliming out, because most of them will have a sublimation point way below that of carbon. Carbon doesn't sublime until about 3800 Kelvin, whereas aluminum, silicon, they all sublime around 26-2800 Kelvin. And there's a big flash of light that accompanies this. And you can see very nice graphene results. The inventor of this is not me is Duy Luang. And he just did a tremendous, tremendous job. We automated the process because we had to deliver a proposal. In two years we had to deliver, go from, you know, doing, the biggest we have ever done was one gram to delivering one kilogram in a day of bottom up graphene made by this flash joule heating method. And so during the COVID shutdown, we were out of our labs for two and a half months. I bought a bunch of 3D printers, sent them home with the students to design and built this system, which picks up a pixel cartridge and flashes it and then here's what the flash looks like. And then it drops out. And we could get 90% starting from something like metallurgical Coke or calcium Coke, where you get over 90% processing yield. And 100% of that is graphene. So we do Raman map over the entire area. And this was during the COVID closure period, but our production rate doubled every nine weeks. You've heard of Moore's law, well this is Dewey's law, the student would do a doubling production rate every nine weeks. So we were able to deliver the DoE goal so that when it finally came time to deliver, we were able to do 10 kilograms in a day. And so now that is further scaling industrially, but what are the advantages of flash graphene?
James Tour 3:20
Well, first of all, graphene is non toxic. It's used in several medical applications. It's naturally occurring in the environment, it's agglomerate to the natural mineral graphite, it's naturally occurring in that you find it if you have graphite and riverbed, some will shear off and you have graphene floating around. It's a terminal natural sink for carbon, since microbial decomposition is really slow. So it's very slow to enter the CO2 cycle again, most carbon assets that you bring up from under the ground are going to end up with CO2 at some point. It can be used in composites of all types, including plastics, which can be reflashed at the end of their lifecycle. So there's this extreme energy savings. That flash process requires no solvent, no water, no purification, self purifying because it gets so hot. Other things sublime out, the cost for us is $35 per metric ton. So we can just put in $35 worth of electricity and convert one tonne of coal into graphene. At the current price of graphene of 60 to 200k per tonne, that's just a big upcycle. So how is this an energy effort? Well, where's the energy going to come from in 20 years? Right now what we do is we take what people do is we take methane, react it with oxygen, combust it to make CO2 and water 800 kilojoules per mole of energy is put out.
James Tour 3:20
I think what will be done in the future is to take these carbon assets, convert them to carbon solid and two moles of hydrogen. Take that hydrogen and put it with oxygen in a fuel cell and just get water. These two reactions combined put out 400 kilojoules per mole. So you get half the energy out, but you end up getting it back because combustion is 25 to 40% efficient because a lot just goes out as heat. This reaction, stripping hydrogens off of carbon, can be 90% efficient, it's actually developed in the 1950s, it was called carbon black, they just didn't know what to do with this, if you just throw this out in the environment becomes fertilizer, plants will take it up, the plants will die, it'll eventually become CO2 again. But it can be very efficient. And there's much more efficient ways of doing this. Now, you put it through molten salts, for example. And then this reaction is 80%. efficient. So you get it back on efficiency, thermodynamically here's the numbers, but you get it back on efficiency. And so what are you going to do with 30 billion tonnes of CO2? What would people do right now is we just throw it out into the atmosphere. So if you strip off these hydrogens, I'm sorry, these oxygens, you'd get 8 billion tons of carbon, what could you do with 8 billion tons of carbon? Turn it into flash graphene. And where can you put that? Well you can put 8 billion tons of carbon in 44 billion tons of concrete that's already made. So you could put it today, in a certain place if you wanted to, but it's going to go into composites of all kinds. How is this an environmental effort? Well, waste food 30 to 40% of all food is discarded in every country because it goes bad. And this forms not just met not just CO2, but also methane in landfills, there is plastic waste, as you know, is a bad problem, rubber tires US has done pretty well. but many other countries have trouble with this. We can take plastic and convert it into graphene. The big problem in waste plastic recycling is separating it into all the different types. We can mix all of these different types together, flash it, and we get beautiful graphene. We can do it with food and all sorts of other things. If it's carbon, we can turn it into graphene. And so this is what we can do with plastics. We can even use engineering plastics, nylons, construction plastics, no problem, flash it, turn it into graphene. You can take a plastic that has been what's called recycled plastic in the sense that they heat plastics up there's lots of these plants around the world that end up getting light metals or heavy metals and you're left with about 10 to 20% of a carbon residue, we take that boom, we turned it into flash graphene, we can take rubber tires or rubber tire char turn it into flash graphene.
James Tour 7:31
Here are some of the advantages of doing it this way with waste plastic: $35 per ton of plastic electricity costs we put into this, so very little electricity because all the energy goes into the sample we're not heating a bit big furnace, and it's only for 10 to 100 milliseconds. There's no sorting mix, it works on mixed waste plastic, there's no pre-washing because we're not affected by organics that are left in there or plasticizers or dyes, adhesives, food waste, doesn't matter inorganics aren’t come flying out. No solvents are needed, no subsequent purification, no low value ash is leftover. This company started Universal Matter. They will be at a tonne per day production by Q2 2022. Here's the CEO and Duy has gone to be with that company. And they should be 100 tons per day in Q2 of 2023. So that's how fast it's scaling, you can go to UniversalMatter.com and watch a little video on the process. So this is going to concrete, we can greatly strengthen concrete, we have shown that you can triple the life of an asphalt road by adding 1%. Now the economics work because you can drive down the price and go into paints, wood composites and metals, steel, aluminum, we will have a GMP line for biological systems. And then we can move this flash technique beyond graphene. We just published this paper on urban mining by flash joule heating. That's a heating printed circuit board. So what do we do with electronic waste right now? It's a big problem, it's the fastest growing waste in the world. 8.8% increase every year.
James Tour 9:08
So we throw away all our electronic devices. And so only 20% of it is recycled. And the recycling is mainly done overseas, we don't deal with it here. Well, you can just take these printed circuit boards or they're ground up mechanically in these machines and then you just flash them and you can get the materials out. You get silver out very well, these others don't come out as easily and so what we do is we add salts if you add sodium fluoride, you can add just Teflon, this is waste Teflon, you can add sodium chloride, you can add CPVC pipe, so there's a lot of halogen in there or sodium iodide and those halogens all within that 100 milliseconds will react with the metals and now they come volatilizing out because the metal highlights have a much higher vapor pressure than the elemental metals. So we use the hair light additives we can get rhodium palladium, silver, gold at over 80% yield. Now this line right here is what you get out if you just use very concentrated acids, and try to leech these things out. So you can see how much more we can get out by our flashing methods, when we get higher than this dotted line, that's our recovery yield, higher than just washing with acids. Because these are encased in different layers it is very hard for the acids to get through that even though you're using 12 molar acids, mineral acids, can we get out the rare earth elements from E waste. So we can take the E waste. And so all of these elements are already around us, it's called urban mining. So this is what we can do and there's a great advantage in doing it this way. We can simultaneously remove the heavy metals in E waste, we can remove the heavy metals such that one flash gets out the mercury to the safe content level. Three flashes because cadmium has such strict standards on cadmium, you see this is less than .006, this is about .005. So you have an order of magnitude harder with cadmium. So we give three flashes, 1,2,3 flashes, each flash is under a second, that lowers the cadmium such that what is remaining is clean enough to be used according to WHO standards as agricultural soil, so we can remove the heavy metals from this. That's how this is again, an environmental play using this flashtool heating. So our work has been funded by the Air Force, Office of Scientific Research Department of Energy and a recent grant from the US Army Corps of Engineers as we scale this up and move it on. So this is our current research group. A lot of the plastic flashing was done by Wala, and Bing Dang, did the flashing for the other metals and also Kevin has done a lot of the flash joule heating for carbon as well. And also, Paul, and then Jacob has done a lot of the machine learning because we're just training these flash systems to adjust themselves in real time. And with that, I'm just going to wrap this up and then stop sharing and just say thank you again for this invitation to be able to share and to be able to be with you. And I hope that these methods continue to go forth and we continue to develop these great methods that are low, unsalted, low on water and where we can do this tremendous upcycling. Thank you!