Renewable and Sustainable Biorefinery: A Patent Review

Biorefineries can refer to forms of fuel production through renewable biomass derivatives, using different structures of lignocellulosic material, such as lignin, hemicellulose, and cellulose. From lignin, we can produce natural binders and adhesives, among other products. With hemicellulose, we can produce emulsifiers, resins, or lubricants, for example. Using cellulose, we can produce fuels, such as ethanol and biodiesel, or even solvents. Fuels from biorefineries can replace, totally or partially, non-renewable fuels that pollute the environment, such as oil. Considering the climate emergency, we are experiencing, the tendency to reduce the availability of oil, and the negative environmental impacts caused by it, fuels obtained through the processing of renewable plant materials present themselves as a good alternative to replacing fossil fuels. Firstgeneration ethanol (1G) can be obtained by fermenting, for example, sugar cane juice. Secondgeneration (2G) ethanol can be obtained by processing lignocellulosic waste. In this process, there must be pre-treatment and hydrolysis of the biomass before the fermentation and distillation processes. Third-generation ethanol (3G) can be obtained through the fermentation of substrate present in microalgae. Fourth-generation ethanol (4G), in turn, involves the integration of production processes from other generations, increasing the efficiency of 2G and 3G processes for ethanol production.

The objective of this study was to investigate the scenario of patent registrations filed both on the google patents platform and espacenet, which proposes the production of fuels from biorefineries, that are renewable and sustainable.

Although there are other lignocellulosic products originating from biorefineries, we will limit ourselves to patents aimed at the production of cellulosic ethanol. The search covered patents filed in the last 5 years (2019-2023). The 10 patents from each of the 3 biotechnological areas were selected, classified as agriculture, environment, and bioprocesses/bioengineering, totaling 30 patents to be analyzed. After selecting patents through the insertion of keywords and Boolean operators, the patents were selected by reading the title, its summary, and, finally, the full document to verify which were aligned with the study.

Analysis of the documents revealed that, in most cases, China leads the way in patent applications involving the use of fuels, such as cellulosic ethanol, which are environmentally renewable and sustainable. The main strategies for the production of renewable and sustainable fuels in the context of biorefineries explore mechanisms for reusing agricultural waste, pre-treatment of residual biomass, and reuse of biorefinery waste, among other technologies.

The future perspective is that the production of renewable and sustainable energy, such as that coming from biorefinery fuels, has solved its challenges and contributes to the growing global energy transition process. Analyzing and incorporating advances found through patent analysis into technological development provides mechanisms for better performance in the biorefinery sector. In addition to innovations, it is possible to analyze economic and environmental challenges, promoting integrated strategies that combine sustainability and commercial viability. Thus, the energy transition can be accelerated with solutions that increase the efficiency and technological innovation of biorefineries.