Removal of disperse dye from alcoholysis products of waste PET fabrics by nitric acid-modified activated carbon as an adsorbent: Kinetic and thermodynamic studies
Removal of disperse dye from alcoholysis products of waste PET fabrics by nitric acid-modified activated carbon as an adsorbent: Kinetic and thermodynamic studies
复制标题
硝酸改性活性炭作为吸附剂去除废旧PET织物醇解产物中分散染料的动力学和热力学研究
DOI：
10.1177/0040517520909510
复制
发表时间：
2020-03-04
影响因子：
2.3
通讯作者：
Li, Yonggui
中科院分区：
文献类型：
--
作者：
Li, Mengjuan;Lu, Jing;Li, Yonggui
脱色技术是废聚对苯二甲酸乙二醇酯(PET)纺织品高质量化学回收利用的关键问题。为解决这一问题，采用硝酸改性活性碳(AC-HNO3)作为吸附剂，脱除涤纶废布糖酵解产物中的C.I.分散红60(DR60)。糖酵解产物为对苯二甲酸二(2-羟乙基)酯(BHET)。用氮气吸附、差热分析(DTG)和元素分析(EA)对AC和AC-HNO3样品的孔结构和表面性质进行了表征。硝酸改性使活性碳的含氧量从12.3%增加到18.0%，增强了染料分子与活性碳之间的静电引力。DR60在AC-HNO_3上的平均脱色率为97.6 ± 0.5%，优于在生炭上的平均脱色率(85.0 ± 1.6%)。BHET的相对白度从40.3 ± 0.9%提高到98.3 ± 1.1%。用准一级和准二级模型研究了DR60在AC-HNO_3上的吸附动力学，并与拟二级模型(R2 = ，0.9999)进行了比较。用Freundlich和Langmuir模型考察了吸附平衡行为。结果表明，朗缪尔模型具有较好的相关性(qmax = 为163.9 mg/g)。用不同温度下的吸附等温线测定热力学参数。根据ΔG0、ΔH0和Ea数据，该吸附过程为物理吸附。
Decolorization technology is a critical problem of high-quality chemical recycling and recovery of waste poly(ethylene terephthalate) (PET) textiles. In order to deal with this problem, nitric acid-modified activated carbon (AC-HNO3) was utilized as an adsorbent for removal of C.I. Disperse Red 60 (DR60) from the glycolysis products of waste PET fabrics. The glycolysis product was bis(2-hydroxyethyl) terephthalate (BHET). The pore structure and surface properties of AC and AC-HNO3 samples were characterized by N2 adsorption, differential thermogravimetric analysis (DTG) and elemental analyses (EA). Modification with nitric acid increased the amount of oxygen groups of the activated carbon from 12.3% to 18.0% and enhanced the electrostatic attraction between dye molecules and activated carbon. The average color removal ratio of DR60 on AC-HNO3 increased into 97.6 ± 0.5%, which is better than that on raw AC (85.0 ± 1.6%). Relative whiteness of BHET increased from 40.3 ± 0.9% to 98.3 ± 1.1%. The adsorption kinetics for DR60 on the AC-HNO3 were studied using pseudo-first order and pseudo-second order models and fitted to the latter well (R2 = 0.9999). To investigate the adsorption equilibrium behavior, Freundlich and Langmuir models were examined. The results showed that the Langmuir model provided better correlation (qmax = 163.9 mg/g). The adsorption isotherms at different temperatures were used for the determination of thermodynamic parameters. Based on the data of ΔG0, ΔH0 and Ea, the adsorption process was physisorption.