【作者】 张帅；

【导师】 赵义平；

【作者基本信息】 天津工业大学 ， 材料科学与工程， 2025， 硕士

【摘要】 工业的快速发展加剧了含油废水的污染问题,生物质气凝胶以其环保性和生物相容性著称,在油水分离领域有广阔前景。但部分生物质气凝胶还存在机械性能差、分离效率低等问题,因此本研究旨在开发具有卓越油水分离及有机污染物去除性能的新型气凝胶材料,并拓展其在卷烟滤嘴领域的应用。首先运用顺序交联法,以壳聚糖（CTS）和纤维素（CE）为原料制备气凝胶,优化了原料配比。采用发散合成法合成了不同代数的聚酰胺-胺（PAMAM）改性壳聚糖（CTS-Gn PAMAM）,借助顺序交联与定向冷冻技术,成功制备了CTS-Gn PAMAM/CE气凝胶。随后,利用甲基三甲氧基硅烷（MTMS）化学气相沉积对其改性,使其具备疏水性。该方法赋予了气凝胶优异的机械性能,包括低密度（0.06-0.11 g/cm³）下的高强度和80%应变下的各向异性,以及高比表面积（1.93-12.56 m²/g）和疏水性（WCA=139.5°）。气凝胶对四氯化碳/水混合物(5501.85L·m^-2·h^-1)和油包水乳剂(4198.60 L·m^-2·h^-1,96.67%)具有出色的分离效率,对阳离子染料Rh B的去除率为61.24%。进一步研究了基于树枝状PAMAM聚合物和疏水基团的“破乳-吸附-分离”协同分离机制,研究发现随着PAMAM代数“n”的增加,油水分离效率先上升后下降。为进一步提升气凝胶的吸附分离性能,以壳聚糖和羧甲基纤维素（CMC）为原料,通过半溶解-酸化法制备了CTS-Gn PAMAM/CMC复合聚电解质物理交联气凝胶,构建了双网络互穿凝胶网络。其中CTS-G2 PAMAM/CMC（M-CG₂MA）气凝胶的油水分离能力出色,密度低至0.039 g/cm³,比表面积提升至10.09 m²/g,表面呈超疏水性（WCA=150.80°）,对各类油的吸附能力大幅提升（11.72-26.39g/g）,油水乳液分离效率高达99.18%。在上述研究基础上,将M-CG₂MA气凝胶与醋酸纤维素滤棒通过分段式组合成复合气凝胶卷烟滤嘴,并进行模拟抽吸测试。结果表明,在实验室与工厂测试条件下,均能有效降低卷烟烟气中总挥发性有机物（Total Volatile Organic Compounds,TVOC）、总粒相物、焦油、烟碱、CO的释放量,且对烟碱降低幅度小,不影响香烟口感。本研究提出了基于树枝状PAMAM聚合物和疏水基团的“破乳-吸附-分离”协同分离机制,揭示了随着PAMAM代数增加,油水分离效率先升高后降低的规律,制备的气凝胶及复合滤嘴在环境修复与烟草减害领域具有很广阔的应用前景。更多还原

【Abstract】 The rapid industrialization has exacerbated oil-contaminated wastewater issues.Biomass aerogels,renowned for their environmental friendliness and biocompatibility,hold significant promise in oil-water separation.However,challenges such as poor mechanical properties and low separation efficiency in some biomass aerogels necessitate the development of novel aerogel materials with superior performance.This study aimed to fabricate advanced aerogels for efficient oil-water separation and organic pollutant removal,and to explore their application in cigarette filters.Firstly,chitosan（CTS）and cellulose（CE）were used as raw materials for the preparation of aerogels using sequential cross-linking method,and the raw material ratios were optimized.Different generations of polyamide-amine（PAMAM）-modified chitosan（CTS-Gn PAMAM）were synthesized by divergent synthesis,and CTS-Gn PAMAM/CE aerogels were successfully prepared with the help of sequential cross-linking and directional freezing techniques.Subsequently,it was modified by chemical vapor deposition of methyltrimethoxysilane（MTMS）to possess hydrophobicity.This method yielded aerogels with outstanding mechanical properties,including high strength at low density（0.06-0.11 g/cm³）and anisotropy under 80%strain,alongside high specific surface area（1.93-12.56 m²/g）and hydrophobicity（WCA=139.5°）.The aerogels demonstrated excellent separation efficiencies for carbon tetrachloride/water mixtures(5501.85 L·m^-2·h^-1)and oil-in-water emulsions(4198.60 L·m^-2·h^-1,96.67%),and achieved a 61.24%removal rate for the cationic dye Rh B.A“demulsification-adsorption-separation”synergistic mechanism based on dendritic PAMAM polymers and hydrophobic groups was proposed,revealing that oil-water separation efficiency first increased and then decreased with increasing PAMAM generation.To further enhance the adsorption and separation performance of aerogels,CTS-Gn PAMAM/CMC composite polyelectrolyte physically crosslinked aerogels were prepared by semi-solvation-acidification method using chitosan and carboxymethyl cellulose（CMC）as raw materials to construct a dual-network interpenetrating gel network.The CTS-G2 PAMAM/CMC（M-CG₂MA）aerogel exhibited exceptional oil-water separation capabilities,with a density as low as 0.039 g/cm³,a specific surface area of 10.09 m²/g,superhydrophobicity（WCA=150.80°）,and significantly improved oil adsorption capacities（11.72-26.39 g/g）,achieving a 99.18%separation efficiency for oil-in-water emulsions.Based on the aforementioned research,M-CG₂MA aerogel was combined with cellulose acetate filter rods through a segmented process to form composite aerogel cigarette filters,which were then subjected to simulated smoking tests.The results showed that under both laboratory and factory testing conditions,the composite material effectively reduced the release of total volatile organic compounds（TVOC）,total particulate matter,tar,nicotine,and CO in cigarette smoke.Notably,the reduction in nicotine was minimal,ensuring that the cigarette’s flavor profile remained unaffected.This study proposes a synergistic separation mechanism based on dendritic PAMAM polymers and hydrophobic groups,revealing that as the PAMAM degree of substitution increases,the oil-water separation efficiency first increases and then decreases.The prepared aerogels and composite filter tips have broad application prospects in environmental remediation and tobacco harm reduction.更多还原