【作者】 王悦；

【导师】 贺诗欣（Shin-Hsin Ho）；

【作者基本信息】 哈尔滨工业大学 ， 环境科学与工程， 2021， 硕士

【摘要】 近年来,抗生素被广泛的应用于改善人类以及动物的健康,以及治疗感染等病症。抗生素的不完全代谢会导致微生物抗生素抗性基因的进化,进而干扰微生物的功能,最后导致病原体更容易传播,对公众的健康构成巨大的威胁。因此,从污水中去除残留的抗生素对于人类健康和水生环境都具有重要意义,寻找以及开发高效的去除抗生素的方法迫在眉睫。吸附因具有操作过程简单,去除效率高,成本低,以及不产生有毒性的中间体等独特的优势而被广泛的应用于水处理。生物炭也因为其高比表面积、高吸水性、对人体无害和发达的孔结构等优点而受到科研工作者的广泛关注。研究了以提取藻蓝蛋白后的藻渣作为生物质,通过化学活化的方法,采用碳酸钠和氢氧化钾作为活化剂和造孔剂,来制备多孔改性藻渣生物炭。将获得的生物炭用于污水中磺胺噻唑的吸附,吸附结果发现,碳酸钠和氢氧化钾改性的生物炭均能在60 min内将磺胺噻唑去除,去除率可达100%。改性后的生物炭的吸附量大幅度提高,且氢氧化钾的最大吸附量由于碳酸钠的,最高可达213.3 mg/g。除此之外,还探究了生物炭投加量、热解温度、造孔剂的浓度、p H、初始污染物的浓度和无机盐离子等因素对吸附体系的影响,结果表明改性后的生物炭吸附磺胺噻唑所受以上因素影响较低。将所有的吸附试验数据进行横纵对比可知,最佳的改性生物炭制备方案为:热解温度800℃,Na₂CO₃:C=1:1、KOH:C=1:1。实验采取了多种表征手段对改性前后的生物炭的表面化学、结构和官能团进行了分析,结果显示碳酸钠和氢氧化钾改性的藻渣生物炭的碳含量均显著升高,可在75%～87%之间,碳含量和芳香化的程度更高,且生物炭内的N元素会发生流失,藻渣生物炭由原来的团块状结构变成了多孔的蜂窝状结构。改性后的生物炭拥有了显著提升的比表面积和孔容,SSAS的变大伴随着平均孔径的降低,改性后生物炭的平均孔径在3～5 nm之间,微孔和介孔比例显著增加,同时KOH的造孔能力优于碳酸钠。除此之外,改性后的生物炭,结晶度显著降低,表面的氧元素的含量大幅降低,含氧官能团减少,石墨化程度升高。通过吸附动力学、吸附等温线和热力学分析探究了吸附体系的吸附机理,结果表明,经过碳酸钠和氢氧化钾改性后的的生物炭吸附磺胺噻唑的过程,均适配于拟一级动力学方程,吸附过程以物理吸附为主;吸附等温线适合Freundlich模型,说明是通过多分子层来进行吸附的,并且随着水中污染物浓度的升高,生物炭的吸附能力也会随之升高,吸附反应较易进行。该过程是放热的,过程为熵减。更多还原

【Abstract】 In recent years,antibiotics have been widely used to improve the health of humans and animals,and to treat infections and other diseases.The incomplete metabolism of antibiotics will lead to the evolution of microbial antibiotic resistance genes,which will interfere with the function of microorganisms,and finally cause pathogens to spread more easily,posing a huge threat to public health.Low-concentration antibiotics are more harmful to human health and the ecological environment than high-concentration antibiotics.Therefore,the removal of residual antibiotics from sewage is of great significance to human health and the aquatic environment,and it is urgent to find and develop efficient methods to remove antibiotics.Adsorption is widely used in water treatment because of its unique advantages such as simple operation process,high removal efficiency,low cost,and no toxic intermediates.Biochar has also received extensive attention from scientific researchers because of its high specific surface area,high water absorption,harmlessness to the human body,and developed pore structure.Researched the use of algae residue after p Hycocyanin extraction as biomass,chemical activation method,using sodium carbonate and potassium hydroxide as activator and pore former to prepare porous modified algae residue biochar.The obtained biochar was used for the adsorption of sulfathiazole in sewage.The adsorption results found that both sodium carbonate and potassium hydroxide modified biochar can remove sulfathiazole within 60 minutes,and the removal rate can reach 100%.The adsorption capacity of the modified biochar is greatly increased,and the maximum adsorption capacity of potassium hydroxide due to sodium carbonate is up to 213.3mg/g.In addition,the effects of biochar dosage,pyrolysis temperature,pore former concentration,p H,initial pollutant concentration and inorganic salt ion on the adsorption system were also explored.The results showed that the modified biochar The carbon adsorption of sulfathiazole is less affected by the above factors.Comparing all the adsorption test data horizontally and vertically,it can be seen that the best modified biochar preparation plan is: pyrolysis temperature 800℃,activator: C=1:1.The experiment adopted a variety of characterization methods to analyze the surface chemistry,structure and functional groups of the biochar before and after the modification.The results showed that the carbon content of the algae residue biochar modified by sodium carbonate and potassium hydroxide was significantly increased,which can be found in Between 75% and 87%,the carbon content and the degree of aromatization are higher,and the N element in the biochar will be lost.The algae residue biochar has changed from the original clumpy structure to a porous honeycomb structure.The modified biochar has a significantly increased specific surface area and pore volume.The increase in SSAS is accompanied by a decrease in the average pore size.The average pore size of the modified biochar is between 3 and 5,and the ratio of micropores and mesopores is significant.At the same time,the pore-forming ability of KOH is better than that of sodium carbonate.In addition,the crystallinity of the modified biochar is significantly reduced,the content of oxygen on the surface is greatly reduced,the oxygen-containing functional groups are reduced,and the degree of grap Hitization is increased.The adsorption mechanism of the adsorption system was explored through adsorption kinetics,adsorption isotherm and thermodynamic analysis.The results showed that the adsorption process of sulfathiazole on the biochar modified by sodium carbonate and potassium hydroxide was all adapted to the pseudo first-order kinetics.According to the equation,the adsorption process is mainly p Hysical adsorption;the adsorption isotherm is suitable for the Freundlich model,indicating that adsorption is carried out through multi-molecular layers,and as the concentration of pollutants in water increases,the adsorption capacity and adsorption capacity of biochar will also be As it rises,the adsorption reaction is easier to proceed.The process is exothermic,and the process is entropy reduction.更多还原