Abstract:
In this study, cow dung biomass was converted into biochar (BC). BC900 was obtained through one-step pyrolysis at 900 °C, while BC700-900 and BC900-700 were obtained via two-step pyrolysis at temperature ranges of 700-900 °C and 900-700 °C, respectively. The primary objective was to investigate the adsorption performance and application value of BCs for tetracycline (TC) in water. The samples underwent characterization using scanning electron microscopy and mapping analysis, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. Subsequently, the effects of reaction time, adsorbent dosage, temperature, pH, and ionic strength were analyzed. Based on the fitting results of adsorption kinetics, the pyrolytic BCs exhibited a better fit with the pseudo-secondary kinetic model. The adsorption isotherm indicated monolayer adsorption on the surface of the adsorbents, with maximum adsorption capacities of 158.93 mg/g for BC900-700, 150.15 mg/g for BC700-900, and 142.56 mg/g for BC900, respectively. Furthermore, results from simulated wastewater and regeneration experiments demonstrated that BC900-700 exhibited not only excellent adsorption performance in wastewater but also remarkable regeneration capabilities. The two-step pyrolysis BCs in this study displayed a higher adsorption capacity compared to the one-step pyrolysis BCs in practical applications. These findings provide insights for further exploring the adsorption mechanism and optimizing the process.
摘要:
在这项研究中,牛粪生物质转化为生物炭(BC)。通过在900°C下一步热解获得BC900,而BC700-900和BC900-700是通过在700-900°C和900-700°C的温度范围内的两步热解获得的,分别。研究BCs对水中四环素(TC)的吸附性能及应用价值。使用扫描电子显微镜和作图分析对样品进行了表征,傅里叶变换红外光谱,X射线衍射,和热重分析。随后,反应时间的影响,吸附剂用量,温度,pH值,并对离子强度进行了分析。根据吸附动力学的拟合结果,热解BCs表现出与伪二次动力学模型更好的拟合。吸附等温线表明单层吸附在吸附剂表面,BC900-700的最大吸附容量分别为158.93mg/g,BC700-900的最大吸附容量为150.15mg/g,BC900的最大吸附容量为142.56mg/g。此外,模拟废水和再生实验结果表明,BC900-700不仅在废水中具有优异的吸附性能,而且具有显着的再生能力。与实际应用中的一步热解BCs相比,本研究中的两步热解BCs具有更高的吸附能力。这些发现为进一步探索吸附机理和优化工艺提供了见解。