Researchers have discovered that using electrolyzed water in the pretreatment of ethanol waste products can create a clean and effective acetone-butanol-ethanol fuel mix.
Previously a similar method aimed at deriving biofuel from ethanol waste products required the use of harsh chemicals like sulfuric acid, which aside from being a pollutant also had ill-effects that made the method impractical. But because electrolyzed water is nontoxic, biofuel can be derived effectively and efficiently from byproducts previously labeled as waste.
When ethanol is made, distiller’s dried grain with solubles (DDGS) is produced as a byproduct. The DDGS has precious sugars which could be fermented to create a biofuel mix, but the sugars in DDGS are locked up in a thick cellulosic corn fiber that has to be broken up. In order to get that sugar out, harsh chemicals like sulfuric acid or a strong lime base must be used.
The problem is that when those chemicals are used in the process, unwanted compounds are generated which kill the microorganisms like the Baker’s yeast used to make ethanol in the first place. Thus, until now the DDGS has been thrown out and used as animal feed instead.
Enter Hao Feng, University of Illinois food scientist. Feng has been experimenting with electrolyzed water as a way to kill bacteria on fresh fruits and vegetables. “We have a machine with two electrodes. Water is neutral, but we use electricity to split the water into two portions with different properties – one is acidic and one is alkaline,” said Feng. He realized that this process shared similar properties to that of using sulfuric acid in the pretreatment of DDGS.
“With the traditional acid method they have to remove the toxicity. With electrolyzed water, there is no need for this detoxification, so this process should be more economical as well. The other advantage of this method is that the traditional method produces a large quantity of solid waste that needs to be handled, and some sugars get consumed in the process as well. We want to maximize the sugar yield so we can maximize the ethanol yield.”
So far this new process has only been performed at the small level of Feng’s laboratory, so its practicality at a largescale level has yet to be tested. But it does bring some excitement in the biofuel world– the fewer byproducts in the biofuel-making process, the more efficient it becomes to utilize biofuel as a replacement to fossil fuels.
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