Rice University and Ford Collaborate to Recycle Graphene from Automotive Plastics Using Flash Heating Process

Researchers at Rice University and Ford have teamed up to turn plastic parts in end-of-life vehicles into graphene using the school's flash Joule heating process,media reported
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(Image credit: Rice University)

An average of 350Kg of plastic is contained in a sports utility vehicle (SUV)
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If not recycled, these plastics could end up in landfills for years and years
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The project, led by Rice chemist James Tour and graduate student and lead author Kevin Wyss, aims to reuse graphene to create reinforced polyurethane foam for new vehicles
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Tests have shown that graphene-added foams (containing only 0.
1% or less of graphene) have a 34% increase in tensile strength and a 25% increase in low frequency noise absorption
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When the new car is scrapped, these foams can be turned into graphene again
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"Ford sent the lab 10 pounds of mixed plastic waste," Tour said
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The material had been shredded through a car shredding facility and was mushy and damp
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The lab flash-heated it and sent the resulting graphene back.
Ford
Inc.
The company added graphene to new foam composites and it worked as expected
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Then Ford sent in the new composites and the lab flash-heated them back to graphene
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It's a good example of recycling
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According to previous studies, the use of plastics in cars has increased by 75% in the past six years alone, in order to reduce weight and improve fuel economy
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Therefore, sorting and recycling mixed plastic waste is one of the long-term problems facing the automotive industry
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At the same time, the issue has become even more critical as environmental regulations are gradually tightened
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"In Europe, automakers have to recycle 95 percent of their end-of-life materials, which is very difficult to do,
" Tour said.

There are hundreds of different combinations of plastic resins, fillers and reinforcements on vehicles that are difficult to separate, and ultimately most of the mixed plastic is incinerated
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"These are not recyclable materials like plastic bottles that cannot be melted and reshaped," Tour said.
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So the Ford researchers turned to Rice's flash-joule heating process
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In 2020, Tour's lab proposed using a "flash Joule heating" method to make graphene, encapsulating a mixture of ground plastic and coke additives (to conduct electricity) between electrodes in a tube, which is then detonated at high pressure
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The sudden high temperature (up to nearly 5,000 degrees Fahrenheit) vaporized other elements and left behind easily soluble mixed-layer graphene
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The process does not require solvents and can substantially reduce energy consumption, thereby significantly improving environmental benefits
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To test whether it is possible to convert waste mixed plastics, the lab uses plastic bumpers, gaskets, floor mats, seats and door shells from end-of-life F-150 pickups without washing or pre-sorting components, which will be The pulverized substance from which the components are made is ground into a fine powder
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During the experiment, the researchers flash heated the powder in two steps
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In specially designed heaters, a small current is passed first, followed by a high current
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Heating these powders for 10-16 seconds at a small current produces a highly carbonized plastic, about 30% of the original volume
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The other 70% is vented as a gas, or recovered as hydrocarbon-rich waxes and oils (which the researchers believe could also be recovered)
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Then, high-current flash heating of the carbonized plastic converts 85% of the plastic into graphene, while releasing hydrogen, oxygen, chlorine, silicon and trace metal impurities
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Combined with life cycle analysis (LCA), the project compares graphene from automotive flash heating components with graphene produced by other methods and evaluates recycling efficiency
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The results show that using flash Joule heating to make graphene can significantly reduce energy consumption, greenhouse gas emissions and water use compared to other methods
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Since 2018, Ford has used up to 60 pounds of urethane foam in its vehicles, about 2 pounds of which are graphene-enhanced urethane foam, said Alper Kiziltas, a Ford Research Center technologist focused on sustainability and emerging materials.

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"Once the graphene was taken from Rice, it was added to the foam in very small quantities and a significant improvement in material properties was seen
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This provided superior mechanical and physical properties for Ford applications beyond expectations
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Ford is clearly serious about using graphene
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The company is introducing graphene into various other under-hood components for the first time, with a graphene-enhanced hood in 2020
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The company is also said to want to use graphene to strengthen hard plastics
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Mielewski said: "As Ford transitions to electric vehicles, the discovery of the partnership with Rice will play an important role
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When the internal combustion engine is no longer noisy, the sound inside and outside the car can be heard more clearly
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Noise reduction is very important, and BMW urgently needs to be able to Better sound-absorbing and vibration-damping foam
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With only a small amount of graphene, you can have good noise mitigation, and that's what it's all about
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