Yang Xinru, Li Xiaoyu, Hou Lining, Liu Ruxue, Zhao Yongsheng
Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, People's Republic of China.
Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, People's Republic of China.
Environ Technol. 2025 Aug;46(20):4123-4134. doi: 10.1080/09593330.2025.2485362. Epub 2025 Mar 31.
Industrial molasses has garnered significant attention in the fields of food, fermentation and environmental remediation due to its abundant nutrients and antioxidant substances. Cr (VI) can be rapidly reduced by molasses in an acidic environment. In this study, the reducing activity of molasses was systematically analyzed. At pH = 2, the reduction of Cr(VI) by molasses followed a second-order kinetic model. As the molasses concentration increased from 5 g/L to 10 g/L, the reaction rate constant rose from 0.43 to 5.21 mM h, and 56 mg/L Cr(VI) was completely eliminated in both systems. The change in polyphenol content in molasses exhibited a consistent trend with the Cr(VI) concentration. Then multiple Cr(VI) spiking experiments demonstrated that molasses contains a variety of substances with different reactivity. The rate constant for the third spike with 10 g/L molasses was 0.18 mM h, significantly lower than that of the initial molasses concentration of 5 g/L (0.43 mM h) under similar polyphenol levels. Moreover, the amount of polyphenols consumed to reduce the same amount of Cr(VI) varied at different spiking stages. UV-Vis, FTIR and 2DCOS revealed that the phenolic hydroxyl groups were the primary active substances involved in the reduction reaction with Cr(VI), and the molar ratio of total polyphenols to Cr(VI) ranged between 0.1 and 0.2. This study provides valuable insights into the dosage of molasses and other parameters for the effective removal of Cr(VI) pollution.
工业糖蜜因其丰富的营养成分和抗氧化物质，在食品、发酵和环境修复领域受到了广泛关注。在酸性环境中，糖蜜能够快速还原六价铬（Cr(VI)）。本研究对糖蜜的还原活性进行了系统分析。在pH = 2时，糖蜜对Cr(VI)的还原遵循二级动力学模型。随着糖蜜浓度从5 g/L增加到10 g/L，反应速率常数从0.43升高至5.21 mM/h，且在两个体系中56 mg/L的Cr(VI)均被完全去除。糖蜜中多酚含量的变化与Cr(VI)浓度呈现出一致的趋势。随后的多次Cr(VI)加标实验表明，糖蜜中含有多种具有不同反应活性的物质。在相似的多酚水平下，10 g/L糖蜜第三次加标的反应速率常数为0.18 mM/h，显著低于初始糖蜜浓度5 g/L时的反应速率常数（0.43 mM/h）。此外，在不同加标阶段，还原等量Cr(VI)所消耗的多酚量也有所不同。紫外可见光谱（UV-Vis）、傅里叶变换红外光谱（FTIR）和二维相关光谱（2DCOS）分析表明，酚羟基是与Cr(VI)发生还原反应的主要活性物质，总多酚与Cr(VI)的摩尔比在0.1至0.2之间。本研究为有效去除Cr(VI)污染时糖蜜的用量及其他参数提供了有价值的见解。
