Abenghal Lahbib, Ratier Adrien, Lamoudan Hamid, Belosinschi Dan, Brouillette François
Innovation Institute in Ecomaterials, Ecoprodcuts and Ecoenergies, Biomass-Based (I2E3), Biochemistry, Chemistry, Physics and Forensic Science Department, Université du Québec à Trois-Rivières, 3351 boul. des Forges, Trois-Rivières, QC G9A 5H7, Canada.
CTT Group, 3000 Av. Boullé, Saint-Hyacinthe, QC J2S 1H9, Canada.
Polymers (Basel). 2025 Jul 24;17(15):2022. doi: 10.3390/polym17152022.
Phosphorylated cellulose is proposed as a bio-resin for the removal of heavy metals, as a substitute for synthetic polymer-based materials. Phosphorylation is carried out using kraft pulp fibers as the cellulose source, with phosphate esters and urea as reactants to prevent significant fiber degradation. Herein, phosphorylated fibers, with three types of counterions (sodium, ammonium, or hydrogen), are used in adsorption trials involving four individual metals: nickel, copper, cadmium, and lead. The Langmuir isotherm model is applied to determine the maximum adsorption capacities at four different temperatures (10, 20, 30, and 50 °C), enabling the calculation of the Gibbs free energy (), entropy (), and enthalpy () of adsorption. The results show that the adsorption capacity of phosphorylated fibers is equal or even higher than that of commercially available resins (1.7-2.9 vs. 2.4-2.6 mmol/g). However, the nature of the phosphate counterion plays an important role in the adsorption capacity, with the alkaline form showing a superior ion exchange capacity than the hybrid form and acid form (2.7-2.9 vs. 2.3-2.7 vs. 1.7-2.5 mmol/g). The thermodynamic analysis indicates the spontaneous ( = (-)16-(-)30 kJ/mol) and endothermic nature of the adsorption process with positive changes in enthalpy (0.45-15.47 kJ/mol) and entropy (0.07-0.14 kJ/mol·K). These results confirm the high potential of phosphorylated lignocellulosic fibers for ion exchange applications, such as the removal of heavy metals from process or wastewaters.
磷酸化纤维素被提议作为一种用于去除重金属的生物树脂，以替代合成聚合物基材料。磷酸化过程以硫酸盐浆纤维作为纤维素来源，使用磷酸酯和尿素作为反应物以防止纤维显著降解。在此，具有三种抗衡离子（钠、铵或氢）的磷酸化纤维被用于涉及四种单一金属（镍、铜、镉和铅）的吸附试验。应用朗缪尔等温线模型来确定在四个不同温度（10、20、30和50℃）下的最大吸附容量，从而能够计算吸附的吉布斯自由能（）、熵（）和焓（）。结果表明，磷酸化纤维的吸附容量等于甚至高于市售树脂（1.7 - 2.9对2.4 - 2.6 mmol/g）。然而，磷酸抗衡离子的性质在吸附容量中起着重要作用，碱性形式显示出比混合形式和酸性形式更高的离子交换容量（2.7 - 2.9对2.3 - 2.7对1.7 - 2.5 mmol/g）。热力学分析表明吸附过程是自发的（ = (-)16 - (-)30 kJ/mol）且是吸热的，焓（0.45 - 15.47 kJ/mol）和熵（0.07 - 0.14 kJ/mol·K）有正向变化。这些结果证实了磷酸化木质纤维素纤维在离子交换应用方面的高潜力，例如从工艺或废水中去除重金属。
