Two-response surface design optimization of carboxylated CNCs with super high thermal stability and dye removal capability
writer：Bowen Jia, Xiang Chen, Yunfei Shen, Zilu Li, Xue Ma, Hou-Yong Yu
keywords：Carboxylated cellulose nanocrystals, Response surface, Dye adsorption, Thermal stability, Yield , Dynamics and thermodynamics
source：期刊
Issue time：2024年
Discharging wastewater from industrial dyeing and printing processes poses a significant environmental threat, necessitating green and efficient adsorbents. Cellulose nanocrystals (CNCs) have emerged as a promising option for dye adsorbing. However, the industrial production and commercialization of CNCs still faced low yield, time-consuming, and uneco-friendly. In this study, we proposed a facile hydrochloric/maleicacid (HCl/C4H4O4) hydrolysis method to synthesize carboxylated CNCs using Box-Behnken design and dual response surface design, which can systematically investigate the effect of experimental factors (temperature, time and HCl/C4H4O volume ratio) on the final products. The rod-liked carboxylated CNCs gave the highest yield of 90.50%, maximum carboxyl content of 1.29 mmol/g, and efficient dye removal ratio of 91.5%. Furthermore, compared to CNCs obtained by commonly sulfuric acid hydrolysis way(CNCs-S) with a Tmax of 242.6 °C, the CNCs extracted at 5 h exhibited significantly improved thermal stability with Tmax reaching 351.2 °C. The enriched carboxyl content and excellent thermal stability show potential wastewater treatment applications under harsh conditions