Microalgae May Create the Green Roads of the Future

Microalgae may be the fuel of the future. Scientists have found that microalgae offer a highly promising alternative to petroleum products without competing for resources used in the food industry.

Microalgae have long been known for their use in applications such as cosmetic dyes and food supplements. In more recent years, it's also been suggested that microalgae could be refined and, in theory, produce biofuels. Now they're being recognized as a promising alternative to petroleum.

As part of the "Algoroute" program, researchers have produced bioasphalt from microalgae residues by extracting hydrosoluble proteins for the cosmetics industries. The scientists used a hydrothermal liquefaction process (whichis pressurized water in a subcritical state) in order to transform microalgae waste into a black, viscous hydrophobic substance that closely resembles petroleum-derived asphalt. The current process achieves a conversion efficiency of 55 percent.

Even though the chemical composition of bioasphalt is completely different from its petroleum-derived counterpart, they have similarities, including their black color and rheological properties. The bioasphalt can be used to coat mineral aggregates and can also ensure the cohesion of the granular structure while supporting mechanical loads and relaxing stress.

Currently, trials are underway to analyze the material's behavior over time, as well as its cost-effectiveness.

The new material could be huge for the road building industry in the future. Although this industry is entirely dependent on petroleum today, the new bioasphalt may provide an alternative in the future.

The findings are published in the journal ACS Sustainable Chemistry & Engineering.

For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).