Abstract:

This study aimed to prepare a high-performance adsorbent (highly active coal gasification slag, HCGS) to adsorb sulfadiazine (SDZ) from industrial wastewater. HCGS was synthesized through the hydrothermal modification of solid waste coal gasification slag (CGS). This study analyzed and explored the physicochemical properties, adsorption performance and mechanisms. The modification of CGS under different acid concentrations and temperature conditions was conducted, with Pearson correlation analysis performed on the leaching of oxides, Si−OH content, and adsorption performance under various modification conditions. The adsorption conditions were explored, and the materials were characterized using XRD, FT-IR, SEM, BET, and XPS. The results demonstrated that the optimal modification temperature was 80 ℃ and the mass fraction of hydrochloric acid was 16%. The specific surface area of HCGS reached 326 m²∙g⁻¹, and its adsorption capacity for SDZ reached 24.8 mg∙g⁻¹. The modification mechanism was primarily attributed to the formation of silanol groups and the protonation of hydroxyl groups. The optimal adsorption conditions included 180 min contact time, initial SDZ concentration of 20 mg∙L⁻¹, pH of 8, and adsorbent dosage of 30 mg. The adsorption kinetics followed a quasi-second-order kinetic model, indicating a heterogeneous diffusion process dominated by chemical adsorption. The intra-particle diffusion model suggested that the adsorption process was influenced by additional factors beyond intra-particle diffusion. The adsorption mechanism was related to hydrogen bonding and electrostatic interactions. This study converted CGS into high-performance and low-cost adsorbent materials, achieving the dual goals of solid waste resource utilization and antibiotic pollution control, and providing a theoretical basis and technical support for the treatment of antibiotic industrial wastewater.

Key words: sulfadazine, coal gasification slag, modification, adsorption, aquatic environment

摘要：

为了吸附工业废水中的磺胺嘧啶（SDZ），该研究旨在将固体废弃物煤气化渣（CGS）进行水热改性，制备出吸附性能良好的吸附剂——改性煤气化渣（HCGS），并分析和探索其物理化学特性、吸附性能及机理。通过对CGS进行不同酸浓度和温度条件下的改性处理，对不同改性条件下氧化物浸出量、硅羟基（Si−OH）含量和吸附性能的皮尔逊相关性进行分析，对吸附条件进行探究，结合XRD、FT-IR、SEM、BET、XPS等表征分析，结果表明，最佳改性温度为80 ℃、盐酸质量分数为16%；HCGS比表面积可达326 m²∙g⁻¹、对SDZ的吸附量可达24.8 mg∙g⁻¹；改性机制主要与硅羟基的生成和羟基质子化有关；最佳吸附时间为180 min，SDZ的初始质量浓度为20 mg∙L⁻¹，pH为8，吸附剂投加量为30 mg；吸附过程符合准二级动力学模型，是以化学吸附为主的非均相扩散过程；颗粒内扩散模型表明吸附过程除内扩散之外还受到其他因素的影响；吸附机理与氢键和静电作用有关。该研究将CGS转化为高性能低成本的吸附材料，实现固废资源化与抗生素污染治理的双重目标，为抗生素工业废水治理提供了理论基础与技术支持。

关键词: 磺胺嘧啶, 煤气化渣, 改性, 吸附, 水环境