Recycling of Mixed Plastics, Foam to Graphene - Rice University

将废弃的汽车塑料废物覆盖成石墨烯

Flash Joule heating process recycles plastic from end-of-life Ford trucks into high-value graphene for new vehicles
一辆变成石墨烯的旧车的一部分可能是新车的更好部分。

赖斯大学的化学家和研究人员一起工作at the Ford Motor Company are turning plastic parts from “end-of-life” vehicles into graphene via the university’s flash Joule heating process.

The average SUV contains up to 350 kilograms (771 pounds) of plastic

The goal of the project led by Rice chemist James Tour and graduate student and lead author Kevin Wyss was to reuse that graphene to make enhanced polyurethane foam for new vehicles. Tests showed the graphene-infused foam had a 34% increase in tensile strength and a 25% increase in low-frequency noise absorption. That’s with only 0.1% by weight or less of graphene.

And when that new car is old, the foam can be flashed into graphene again.

“Ford sent us 10 pounds of mixed plastic waste from a vehicle shredding facility,” Tour said. “It was muddy and wet. We flashed it, we sent the graphene back to Ford, they put it into new foam composites and it did everything it was supposed to do.

他说：“然后他们向我们发送了新的复合材料，我们将它们闪烁，并将它们变成石墨烯。”“这是循环回收的一个很好的例子。”

数百种不同组合的塑料树脂，填充物和车辆上的增援使这些材料非常难以分离。FlashJoule加热以制造石墨烯，由Tour Lab于2020年推出，包装混合地面塑料和可乐添加剂（用于电导率）在管中，用高电压爆炸。突然，强烈的热量 - 华氏度近5,000度 - 使其他元素蒸发，并将其叶子留在易于溶解的涡轮质石墨烯。

Flash heating offers significant environmental benefits, as the process does not require solvents and uses a minimum of energy to produce graphene.

To test whether end-of-life, mixed plastic could be transformed, the Rice lab ground the shredder “fluff” made of plastic bumpers, gaskets, carpets, mats, seating and door casings from end-of-life F-150 pickup trucks to a fine powder without washing or pre-sorting the components.

The lab flashed the powder in two steps, first under low current and then high current in a heater Wyss custom designed for the experiment.

在低电流中，粉末在10到16秒之间加热，产生了高度碳化的塑料，约占初始体积的30％。其他70％的蜡和富含碳氢化合物的蜡和WYS建议的油也可以回收。

The carbonized plastic was then subjected to high-current flashing, converting 85% of it into graphene while outgassing hydrogen, oxygen, chlorine, silicon and trace metal impurities.

The Life Cycle Analysis involved comparing graphene from flashed car parts to that produced by other methods, and evaluating recycling efficiency. Their results showed flash Joule heating produced graphene with a substantial reduction in energy, greenhouse gas emissions, and water use when compared to other methods, even including the energy required to reduce the plastic shredder fluff to powder.

石墨烯在福特有未来。该公司首先将其引入各种其他下层组件，并在2020年增加了石墨烯增强的发动机盖。Kiziltas表示，该公司希望使用它来增强硬塑料。

Source: Rice University