Potential of hemp (Cannabis sativa L.) for paired phytoremediation and bioenergy production

• Published in: Global change biology. Bioenergy Vol. 13; no. 4; pp. 525 - 536
• Main Authors: Rheay, Hanah T., Omondi, Emmanuel C., Brewer, Catherine E.
• Format: Journal Article
• Language: English
• Published: Oxford John Wiley & Sons, Inc 01.04.2021; Wiley
• Subjects: Agricultural production; Alternative energy sources; Anaerobic digestion; biodiesel; bioethanol; biogas; Biomass; Cannabidiol; Cannabis; Cannabis sativa; combined heat and power; Contaminants; Costs; Crops; Fermentation; Fractionation; Functional foods & nutraceuticals; Genetics; Harvest; Heavy metals; Hemp; Literature reviews; Marijuana; Metabolomics; Nuclear power plants; Organic compounds; Organic contaminants; Personal grooming; phytoextraction; Phytoremediation; Radioisotopes; Renewable energy; Seeds; Soil contamination; Sorghum; Transesterification; United States > US
• ISSN: 1757-1693; 1757-1707
• DOI: 10.1111/gcbb.12782

Hemp (Cannabis sativa L.) is a multi‐use crop that has been investigated for its potential use in phytoremediation of heavy metals, radionuclides, and organic contaminants, and as a feedstock for bioenergy production. A review of research literature indicates that hemp is a suitable crop for phytoremediation, and a competitive option for bioenergy. Coupling phytoremediation and bioenergy production from a single hemp crop is a potential solution to overcoming the economic constraints of phytoremediation projects. The current challenge is ensuring that the extracted contaminants are not introduced into the consumer marketplace. After several decades of limited research on hemp in the United States, the purpose of this review is to identify the knowledge available for hemp applications in phytoremediation or in production of bioenergy, and if and how those two purposes have been combined. The literature shows that hemp growth has been demonstrated successfully at the field scale for phytoremediation and in several bioenergy conversion technologies. Little is known about the fate of contaminants during hemp growth or during post‐harvest processing, especially the relationships between hemp genetics, metabolomics, and contaminant partitioning. Complicating the understanding is the expectation that contaminant fate will be dependent on the contaminant type, the concentration in the material, and the processing methods. Before hemp from phytoremediation applications can be used for bioenergy, the fractionation of heavy metals, radionuclides, and/or organic compounds during transesterification, anaerobic digestion, fermentation, and/or combustion of hemp must be evaluated. Among the contaminants that hemp may uptake are heavy metals, radionuclides, and organics; little is known about the fate of those contaminants in the end‐use products (biofuels, materials, and chemicals) from different parts of the hemp plant.