Techno-economic analysis and life cycle assessment of cellulose nanocrystals production from wood pulp

Cellulose nanocrystals (CNCs) are biobased materials with many desirable properties such as high aspect ratio, mechanical strength, crystalline nature, and biodegradability. This study developed a commercial-scale process model of CNC production from wood pulp using sulfuric acid treatment and evaluated its techno-economic and environmental performance with and without acid recovery. The results indicated that CNC produced with acid recovery process was financially more profitable with higher project net present values than without acid recovery process but required higher capital which resulted in a longer payback period and lower return on invested capital. The estimated minimum selling prices of CNC produced with and without acid recovery were $4.69/kg and $4.89/kg, respectively. The global warming (GW) impacts of 1 kg CNC production with and without acid recovery were 11.39 and 11.18 kgCO₂eq, respectively, showing that higher steam use and consequently more fossil fuels were needed in the acid recovery process.