Cellulose Nanocrystals from Sugar Cane Bagasse Using Organic and/or Inorganic Acids: Techno-Economic Analysis and Life Cycle Assessment

Abstract

The isolation of cellulose nanocrystals (CNCs) by organic acid hydrolysis can contribute to reducing the extensive use of mineral acids, but aspects related to performance, cost effectiveness, and sustainability still need to be addressed. Here, techno-economic analysis (TEA) and life cycle assessment (LCA) were performed to evaluate the production of CNCs using organic and/or inorganic acid hydrolysis, in the context of a sugar cane biorefinery. CNCs were extracted from sugar cane bagasse using sulfuric acid (S-CNC), citric acid (Cit-CNC), and their combination (Cit-S-CNC). The nanodimensional structures were highly dependent on the type of acid used, but all the conditions resulted in nanostructures with CNC characteristics. The minimum product selling price values calculated by TEA for Cit-CNC and Cit-S-CNC were 34.0% and 37.2% higher, respectively, compared to S-CNC, mainly due to the high cost of citric acid recovery. The citric acid hydrolysis and recovery steps had substantial environmental impacts, accounting for up to ∼58% of the gobal warming potential values for Cit-CNC and Cit-S-CNC, which were more than 2fold higher than for S-CNC. These findings showed the importance of using TEA and LCA tools to support decision making in the selection of nanocellulose isolation routes in future biorefineries.

Citrated cellulose nanocrystals from post-consumer cotton textiles

“…Concerning CitCNC extraction (S3), the hydrolysis step was the most dominant contributor (Figure 7b) due to the usage of citric acid, whose production contributes to all 16 impact categories. A similar finding is reported by Bondancia et al 29 . A contribution analysis of S1 and S2 can be found in SI (Figure S7-S8).…”

“…7b) due to the usage of citric acid, whose production contributes to all 16 impact categories. A similar nding is reported by Bondancia et al 29 A contribution analysis of S1 and S2 can be found in ESI (Fig. S7 and S8 †).…”

“…Despite the high uncertainty of laboratory data, implementing LCA studies in the early stages can assist in identifying hotspots 24 which can facilitate future scale-up. Multiple studies have been done assessing the environmental impact of the production and/or applications of cellulose nanofibrils [25][26][27] and CNCs [28][29][30] . For example, Bondancia and colleagues 29 assessed the environmental performance of the extraction of CNCs from sugar cane bagasse through organic and/or inorganic acid hydrolysis and showed the environmental burden of using citric acid as hydrolysis media.…”

Nanocellulose-Based Nanocomposites for Sustainable Applications: A Review

“…Research studies have looked into the idea of employing different mineral or organic acids as an alternative to the conventional sulfuric acid approach to producing CNC. Techno-economic analysis (TEA) by Bondancia et al [277] revealed that the cost of the citric acid applied in the hydrolysis had a significant effect on the minimum selling price (MSP) of CNC, which was relatively higher at USD 16,460 per dry ton. The capital cost of CNC production via citric acid hydrolysis was USD 7,000,000, which was comparatively lower.…”

Citric Acid Recovery and Methanol Production from a Waste Food Fruit Sample by Thermal Decomposition of a Reusable Zinc Citrate Complex

“…Despite the fact that ion-exchange resin adsorption yields high selectivity and efficiency, the resins need to be continually replaced and regenerated, which results in the generation of a substantial volume of solid and liquid waste . Furthermore, membrane separation techniques such as ultrafiltration, electrodialysis, electrodeionization, and perstraction are considered as potential ways for recovering CA from fermentation broth. − In their works, CA recovery has been dominated by the electrodialysis method using bipolar membranes, which relies on the electromigration of ions across ion exchange membranes for the separation of impurities and organic acid concentration from an aqueous solution. However, these techniques still have limitations that restrict them from being used in large-scale production, including the stability and cost of the membranes, use of harmful chemicals, and high-power consumption.…”