超高交联吸附树脂的合成及其对水杨酸的吸附性能

以甲苯、苯甲醇和氯甲醚为基本原料, 一锅法合成了极性超高交联吸附树脂HH-1;利用树脂HH-1上残留的大量未反应完全的氯甲基, 加入苯胺对树脂HH-1进行了后交联反应, 得到比表面积更大的超高交联吸附树脂HH-2。并对两种树脂进行了分析表征, 分析结果表明, 树脂HH-1和树脂HH-2的比表面积分别为67.85m²/g和555.22m²/g, 平均孔径分别为1.882nm和1.105nm。以亲水性小分子水杨酸作为吸附对象, 研究了两种树脂对水杨酸的吸附行为。结果表明, 交联后树脂HH-2对水杨酸的吸附能力是交联前树脂HH-1的5倍。主要原因是二次交联后, 树脂的比表面积得到了大幅度提高。     

新型富氮噻咯超交联聚合物的合成及其气体吸附

有机微孔聚合物(MOPs)在气体存储、吸附分离和非均相催化等领域具有优良性质而广受关注。近年来,超交联微孔聚合物的研究成为MOPs领域中的热点。本文分别以双三苯胺基和双9-(4-甲苯)咔唑基取代的2,5位硅杂环戊二烯为基本构筑单元通过Friedel-Crafts反应,在外加交联剂FDA和无水催化剂FeCl_3催化下制备两种超交联微孔聚合物,研究了结构组成对制备聚合物孔道性能和气体吸附性能的影响。氮气吸附测试结果表明,聚合物的BET比表面积的范围在711～947 m~2·g~(-1)。由于骨架中含有富氮基团以及具有较大的比表面积,在273 K/113 k Pa条件下,PPMCz S的CO_2吸附能力为2.45 mmol·g~(-1)。此外,PPMTPAS和PPMCzS具有优良的选择性吸附性能,对CO_2/N_2的选择性吸附分别是49.7和52.02。     

含氧超高交联树脂的合成及其对苯酚的吸附性能

以苯甲醇和氯甲醚为原料,采用一锅法合成了一种新型含氧超高交联吸附树脂OCHR,并用红外、元素分析和BET法对其化学结构、比表面积及孔径分布进行了分析。结果表明：OCHR树脂比表面积可达525 m²/g,氧含量为6.50%。在相同条件下用XAD-4吸附树脂作对照,比较了它们对水溶液中苯酚的静态吸附能力,除此以外,对树脂OCHR对苯酚的吸附动力学也进行了研究。结果表明,在比表面积远小于XAD-4的情况下,OCHR对水溶液中苯酚的吸附量是XAD-4的2.22倍。树脂OCHR的优良吸附效果归因于树脂上含有的大量氧。     

离子交换纤维微观形貌特点及结构修饰研究

利用比表面积测试仪、扫描电子显微镜等物理化学方法对颗粒与纤维状离子交换剂的链间交联与微观形貌进行了研究,通过刚性交联剂对聚丙烯-苯乙烯-二乙烯基苯(PP-ST-DVB)离子交换纤维骨架结构进行了修饰改造。结果表明:离子交换纤维由于不能通过交联剂与致孔剂参与下的单体聚合构建具有丰富微孔的高分子骨架,所以不存在丰富孔结构和高比表面积特征,其内部为连续凝胶相结构;外比表面积大、传质距离短、交联键分布均匀是其反应动力学和渗透压稳定性能优异的主要原因;刚性交联剂在PP-ST-DVB纤维上的附加交联反应使其比表面积从原来的0.5 m~2/g提高到200 m~2/g以上,附加交联反应所形成的分子尺度微孔孔径分布窄,具有超高交联树脂的结构特点。     

β-环糊精修饰的乙烷桥键有序介孔有机硅材料的合成及应用

该文用“嫁接”的方法将β-环糊精（β-CD）修饰在乙烷桥键有序介孔有机硅材料（PMO）上,并以同样的方法合成了β-CD修饰的介孔材料SBA-15作为对比材料。通过傅里叶红外光谱（FTIR）、高分辨透射电镜（HRTEM）、X射线粉末衍射（XRD）、氮气吸附以及热分析（TGA）实验对修饰前后的PMO材料进行表征。考察了修饰前后PMO材料对于水中污染物苯胺和对苯二酚的吸附性能,由结果可知,β-CD修饰的乙烷桥键有序介孔有机硅材料（PMO-CD）对于苯胺的吸附量为1.54mg/g,相对于PMO材料而言,其吸附能力被极大的抑制,而其对于对苯二酚的吸附量为12.94mg/g,吸附性能得到了很大的提高。因此,PMO-CD在处理水中污染物领域具有潜在的应用价值。     

改性膨润土对苯胺与苯酚混合液的吸附性能

研究酸活化膨润土和有机改性膨润土对苯胺和苯酚混合溶液的吸附性能,结果表明,酸活化膨润土对苯胺的吸附效果明显优于苯酚,具有较强的吸附选择性;有机膨润土对苯胺和苯酚的吸附无明显差别。吸附动力学研究表明,酸活化膨润土与有机改性膨润土对苯胺的吸附均符合准二级吸附动力学模型,相关系数分别为R²=0.999 8和R²=0.997 9。酸活化膨润土对苯胺的吸附符合Freundlich等温线模型,有机膨润土对苯胺的吸附数据对Freundlich等温线模型与Langmuir等温线模型均有较好的拟合。     

褐煤气化半焦对地下水有机污染的模拟脱除

通过自制的煤炭地下气化模拟系统,采用富氧空气/水蒸气两阶段气化工艺,完成内蒙褐煤的地下气化模拟实验。利用傅里叶红外光谱、低温氮气物理吸附仪和扫描电镜对气化残留半焦的表面官能团、孔结构及表面形貌进行表征,进而考察了半焦对苯酚模拟废水中苯酚及煤气洗涤水中总有机碳（TOC）的脱除效果。实验结果表明：半焦孔径主要分布在1~4nm之间,表面有较丰富的含氧官能团及较多的孔洞和裂隙,其孔结构、含氧官能团及孔洞裂隙均有利于污染物在半焦内的迁移和吸附;气化半焦对苯酚的吸附符合Langmuir等温吸附模型,为单分子层吸附;实验条件下最大吸附率为97.95%,吸附量为2.44mg/g;气化半焦对煤气洗涤水中TOC的脱除随吸附时间的变化具有阶段性,脱除率可达88.1%。     

大孔超高交联聚苯乙烯树脂的硝化修饰及吸附性能研究

用大孔超高交联聚苯乙烯树脂(简称HPS树脂)进行硝化反应,得到了硝化修饰的大孔超高交联聚苯乙烯树脂(简称HPS-NO_2树脂)。红外分析、元素分析测定了HPS-NO_2树脂的硝化程度;通过交换量测定确定了HPS-NO_2树脂因氧化反应引入羧基的量。采用氮气吸-脱附法测定了HPS、HPS-NO_2树脂的比表面积和孔结构参数。并考察了HPS、HPS-NO_2树脂对水溶剂、环己烷溶剂中苯酚和苯胺吸附机理及性能。     

甲苯分子在铝基金属-有机骨架材料上的吸附特性

应用巨正则系综蒙特卡罗模拟（GCMC）方法研究了298K下甲苯在4种铝基金属-有机骨架材料（Al-MOF）上的吸附特征。通过对比模拟与实验结果,发现Dreiding力场能够较好地描述甲苯在Al-MOF上的吸附行为。由于4种Al-MOF材料均具有丰富的微孔结构,使得其甲苯吸附量（取1.5kPa时吸附量值比较）均高于传统吸附剂的吸附量（一般小于400mg/g）,分别为1375mg/g （MIL-101）、866mg/g（CYCU-3）、807mg/g（MOF-519）、504mg/g（CAU-3-BDC）。通过Snapshot图和密度分布曲线分析了甲苯在Al-MOF中的吸附位,结果表明,在低压（低负载量）时,甲苯优先吸附在骨架中的小孔道内,随压力（负载量）的增大,甲苯分子逐渐填充到大孔道。此外,甲苯与有机配体的相互作用强于与金属簇的相互作用,说明有机配体处为优先吸附位。将298K、1.5kPa条件下甲苯吸附量与MOF的物理性质相关联,结果发现甲苯吸附量的大小与吸附剂的比表面积、孔容积成线性正相关,而与骨架密度成反比关系。     

枸杞杆制活性炭对亚甲基蓝的吸附研究

以宁夏农业废弃物枸杞杆为原料,用不同的活化剂分别制备磷酸-活性炭（P-AC）、氢氧化钾-活性炭（K-AC）、磷酸-氢氧化钾-活性炭（P-K-AC）,利用比表面积测试（BET）、X射线衍射（XRD）、红外光谱（FT-IR）、扫描电镜（SEM）解析活性炭的孔结构和表面特性,并探究活性炭对水溶液中亚甲基蓝（MB）的去除效果。研究结果表明：P-K-AC比P-AC、K-AC具有更大的比表面积（1 519.84 m²/g）和总孔体积（0.81 cm³/g）,P-AC、K-AC、P-K-AC的平均孔径分别为5.28、2.58、1.99 nm,P-K-AC以微孔为主,K-AC、P-AC均为介孔。3种活性炭表面均分布着丰富的含氧官能团和大量的无定型碳,为吸附MB提供了活性位点。在25 ℃条件下,将10 mg的P-AC、K-AC、P-K-AC分别加入50 mL质量浓度为100 mg/L的MB溶液中用于吸附MB实验。结果表明：P-K-AC的吸附效果最好,吸附率达到95%、吸附量为480.81 mg/g;其次是K-AC,吸附量为352.26 mg/g;P-AC吸附量最小,为225.01 mg/g。P-AC,K-AC、P-K-AC对MB的吸附过程都符合伪二级动力学模型、颗粒内扩散模型和Langmuir等温吸附模型。     

Importance of Surface Area and Pore Size Distribution of Resin for Organic Toxicants Adsorption

Adsorption of benzoic acid and reactive brilliant blue 4 (RBB4) by hypercrosslinked resins and macroporous resins was examined. Micropore areas were much higher in the hypercrosslinked resins than macroporous resins while the pore volume and average pore diameter of macroporous resins were superior to the hypercrosslinked resins. The investigation showed that the pore size distributions of the resins significantly influenced the adsorption capacity of adsorbents. Adsorption of benzoic acid was dominated by BET surface area and the micropore area while the adsorption of RBB4 shifted to a pore-size-dominant process. The maximum mol adsorption capacities of benzoic acid were all higher than those of RBB4 by the resins, showing the influence of the molecular dimension on adsorption. The adsorption thermodynamic parameters were calculated and it revealed that the adsorption was an exothermic, spontaneous, and more ordered process. Adsorption kinetics and elution processes were also investigated for establishing the appropriate adsorption conditions for purifying wastewater containing benzoic acid or RBB4.     

超高交联树脂对水溶液中山梨酸的吸附研究

研究了NDA-150超高交联吸附树脂对水溶液中山梨酸的静态吸附行为,探讨了pH值、温度、盐度以及乙醇的含量等因素对山梨酸在NDA-150树脂上吸附的影响。实验结果表明,该树脂对山梨酸的吸附能力明显优于CHA-111和XAD-4树脂,树脂的表面极性和微孔结构在吸附过程中起决定作用。吸附的最佳pH值为3,降低温度有利于吸附,NaCl的存在有利于吸附,乙醇的质量分数大于1%时,吸附量会显著降低。     

层状双金属氢氧化物吸附剂的功能化改性策略

层状双金属氢氧化物（LDHs）是一类阴离子交换能力强、可调性好、热稳定性高、活性位点丰富的纳米吸附材料,在水中污染物的吸附去除方面呈现出巨大潜力。然而,官能团和结构组分的缺陷严重限制了原始LDHs的吸附性能和应用范围。利用不同改性策略对LDHs进行功能化处理,能显著增强LDHs的污染物吸附容量、选择性、稳定性、可回收性以及适用范围。该文从LDHs吸附水中污染物性能的优化出发,重点综述了当前常用的插层、表面修饰、煅烧、复合组装、包埋、制膜等LDHs功能化改性策略,总结了其与水中各种污染物（无机非金属阴离子、重金属离子、染料以及抗生素）之间的作用机理。此外,还阐述了相应的再生手段。最后,简要提出了功能化LDHs吸附剂的优势以及后期研究可能面临的障碍,并对其广阔的应用前景进行了展望。     

Effective adsorption of phenolic compounds by functional group modified resins: behavior and mechanism

A series of functional hyper-crosslinked resins were successfully synthesized by incorporating amino, hydroxyl, and complex functional groups into post-crosslinked polymer. Possessing high specific surface area and effective functional groups, the newly synthesized resins showed excellent adsorption capacity toward various phenolic compounds. HC-IT displayed huge advantage over the others. Its adsorption capacity for salicylic acid was up to 336 mg/g, which was 3.01–6.64 times higher than that of the commercial resins and 2.33 times higher than its non-functionalized precursor HCLR (144 mg/g). The improved adsorption capacity was attributed to its high specific surface area, good polarity, and proper pore structure.     

Evaluating Adsorptive Separation of Aniline from Aqueous Solution by an Aminated Hypercrosslinked Polymer

In the present work, a modified hypercrosslinked polymeric resin (AH-1) with tertiary amino groups was adopted for adsorbing aniline from aqueous solution, and a traditional hypercrosslinked polymeric adsorbent NDA-100 was selected for comparison. Favorable aniline adsorption was observed at higher solution pH in the range of 5–11, and a further decrease of solution pH resulted in a marked decrease of adsorption capacity. The fact that AH-1 had higher adsorption capacity than NDA-100, would be attributed to the enhanced adsorbent-adsorbate interaction for tertiary amino group introduced on the polymeric matrix. The adsorption process was found to be exothermic and data conformed to the Freundlich equation. In addition, the adsorption kinetic study testified that a pseudo-second kinetic mechanism for the adsorption system, and the rate constant of AH-1 was larger than that of NDA-100. More favorable adsorption of aniline onto AH-1 than NDA-100 was further demonstrated by column adsorption runs which indicated that aniline could be effectively removed from aqueous solution by AH-1. Moreover, AH-1 exhibited a better desorption performance than NDA-100, nearly 100% regeneration efficiency for the spent AH-1 was achieved by 5% hydrochloric acid for its repeated use, implying its potential application in associated wastewater treatment.     

金属-有机骨架材料用于水中痕量药物污染物的吸附脱除

由于其结构复杂、多态性和多个电离位点等特点，水中的药物污染物很难达到完全脱除。因此，寻找一种高效的吸附剂，对降低此类污染物对人体和环境的影响是至关重要的。金属-有机骨架材料（metal-organic frameworks，MOFs）具有超高比表面积/孔隙率、高度化学/结构可调性以及可设计性等优点，在液相吸附分离中表现出优异的性能。本文简述了近年来MOFs材料、功能化MOFs材料以及MOFs衍生碳材料用于水中痕量抗生素和其他类药物污染物脱除的研究进展。针对特定的药物分子，通过引入特定的官能团及其他物质（如多壁碳纳米管、磁性Fe₃O₄等）可以有效提高吸附能力。此外，通过分析MOFs与药物分子之间的相互作用力，包括静电作用、氢键、π-π相互作用等，并结合本文作者课题组的研究内容，认为今后的研究重点是利用先进的理论计算方法定向筛选或设计高效吸附材料，并充分考虑动力学吸附，以实现水中痕量药物污染物的高效脱除。     

Supermacroporous polydivinylbenzene cryogels with high surface area: Synthesis by solvothermal postcrosslinking and their adsorption behaviors for carbon dioxide and aniline

Cryogels are supermacroporous but restricted by lack of surface area in utilization to date. We here propose a method for fabrication of supermacroporous polydivinylbenzene (PDVB) cryogels with high surface area by redox-initiated cryopolymerization combined with solvothermal postcrosslinking technique. The PDVB precursor cryogels are prepared by redox-initiated cryopolymerization, followed by postcrosslinking of residual double bonds to form hypercrosslinked cryogels under solvothermal conditions. The hypercrosslinked cryogels maintain the original supermacroporosity and display very high surface area up to 1462 m² g⁻¹. We demonstrate the utilization of the resultant cryogel in uptake of carbon dioxide (7.9 wt % at 1 bar and 62.2 wt % at 25 bar, respectively) and uptake of aniline (333.3 mg g⁻¹ at room temperature) from aqueous solutions. The adsorption behaviors of aniline on the hypercrosslinked cryogels are found to follow Langmuir model as well as Freundlich model in equilibrium adsorption and to follow pseudo-second-order model in kinetic adsorption, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47716.     

Separation of gibberellic acid (GA3) by macroporous adsorption resins

The adsorption effects of several macroporous adsorption resins for gibberellic acid (GA3) were investigated. The dynamic adsorption capacity is 58.38 mg/g dry beads for resin R4 and 96.46 mg/g dry beads for resin R5 which is consistent with the surface area. Aqueous methanol (50%, V/V) is a good eluent and the yield of GA3 is above 95%. The concentration of GA3 could increase five-fold after an adsorption-elution cycle and this is important when considering further crystallization of GA3 in an industrial process.