Cheng Gege, Li Wenwen, Li Long, Lei Fuhou, Liu Xiuyu, Huang Qin
School of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning 530006, China.
Key Laboratory of Chemistry and Engineering of Forest Products, State Ethnic Affairs Commission, Nanning 530006, China.
Polymers (Basel). 2022 Jun 14;14(12):2397. doi: 10.3390/polym14122397.
Mineral ions (mainly calcium ions) from sugarcane juice can be trapped inside the heating tubes of evaporators and vacuum boiling pans, and calcium ions are precipitated. Consequently, sugar productivity and yield are negatively affected. Calcium ions can be removed from sugarcane juice using adsorption. This paper described the experimental condition for the batch adsorption performance of rosin-based macroporous cationic resins (RMCRs) for calcium ions. The kinetics of adsorption was defined by the pseudo-first-order model, and the isotherms of calcium ions followed the Freundlich isotherm model. The maximal monolayer adsorption capacity of calcium ions was 37.05 mg·g at a resin dosage of 4 g·L, pH of 7.0, temperature of 75 °C, and contact time of 10 h. It appeared that the adsorption was spontaneous and endothermic based on the thermodynamic parameters. The removal rate of calcium ions in remelt syrup by RMCRs was 90.71%. Calcium ions were effectively removed from loaded RMCRs by 0.1 mol·L of HCl, and the RMCRs could be recycled. The dynamic saturated adsorption capacity of RMCRs for calcium ions in remelt syrup was 37.90 mg·g. These results suggest that RMCRs are inexpensive and efficient adsorbents and have potential applications for removing calcium ions in remelt syrup.
甘蔗汁中的矿物离子（主要是钙离子）会被困在蒸发器和真空煮锅中的加热管内，钙离子会沉淀下来。因此，蔗糖的生产率和产量会受到负面影响。可以通过吸附从甘蔗汁中去除钙离子。本文描述了松香基大孔阳离子树脂（RMCRs）对钙离子的间歇吸附性能的实验条件。吸附动力学由拟一级模型定义，钙离子的等温线遵循Freundlich等温线模型。在树脂用量为4 g·L、pH为7.0、温度为75℃、接触时间为10 h的条件下，钙离子的最大单层吸附容量为37.05 mg·g。根据热力学参数，吸附似乎是自发的且吸热的。RMCRs对重熔糖浆中钙离子的去除率为90.71%。用0.1 mol·L的HCl可有效去除负载RMCRs上的钙离子，RMCRs可循环使用。RMCRs对重熔糖浆中钙离子的动态饱和吸附容量为37.90 mg·g。这些结果表明，RMCRs是廉价且高效的吸附剂，在去除重熔糖浆中的钙离子方面具有潜在应用价值。
