Techno-Economic and Environmental Assessment of Phenolic Resins Production Using Lignin Byproducts from Biorefineries - a Case Study of 100% Phenol Replacement

Phenol formaldehyde (PF) resin is widely used in wood panel industry as an adhesive (more than 3 million metric tons per year globally), due to its unique properties (resistance to water and temperature, chemical durability, and bonding strength). Environmental impacts, health concern, and oil price fluctuations have motivated using renewable materials in PF resin production. Lignin, as the main byproduct from the paper industry and 2-G bioethanol biorefineries, is a promising candidate for petroleum-based phenol substitution in PF resin production for its exceptional phenyl propane units. Currently, less than 5% of the lignin is marketed for formulations of chemicals such as surfactants, adhesives, and anti-oxidants, and the remaining is utilized to generate energy through co-generation systems. Thus, the use of lignin by-product for value-added products such as lignin-formaldehyde (LF) resin can be substantial in promoting the economic and environmental benefits for biorefineries. In this study, we conducted a comparative techno-economic and environmental assessment on the developed LF resins, where lignin replaces 100% of phenol, and a commercially formulated phenol resorcinol formaldehyde (PRF). Industrial-scale process simulation was performed in Aspen Plus based on experimental data, while life cycle burdens were modeled using the TRACI 2.1 impact assessment method in SimaPro. The comparison showed an overall reduction in most environmental impacts for the lignin route, yet the process economics revealed higher cost for this bio-based resin compared to petroleum-based resin. Additionally, the alternative pathways of lignin utilization such as combustion, fast pyrolysis and depolymerization were discussed for economic impacts on the biorefineries.