磁性Fe3O4@PANI复合材料吸附剂的制备及其对Ho(III)离子的吸附行为

稀土是我国不可或缺的重要战略资源,广泛应用于航空航天、军事国防以及新型稀土材料等高科技领域。但是稀土资源在开采和使用过程中不可避免产生大量低浓度稀土废水,在污染水体的同时造成稀土资源的浪费。针对此问题,将磁性纳米Fe3O4与聚苯胺（PANI）相结合制备了磁性复合吸附剂Fe3O4@PANI,通过吸附法对低浓度稀土离子进行富集回收。研究结果表明,外层的聚苯胺有效包裹了内部Fe3O4磁芯,并为其在较低pH的环境下提供了有效保护,使得Fe3O4@PANI相较于Fe3O4对Ho(Ⅲ)离子吸附性能具有显著提升,Fe3O4@PANI的饱和吸附量可达145.48 mg/g,并且吸附过程符合Freundlich模型,三次循环使用后吸附率仍达82.77%。该材料在富集稀土离子方面具有良好的潜力。     

改性生物质吸附剂对水中磷酸盐的去除和回收研究进展

综述了壳聚糖、木质素、生物炭、黏土、单宁和淀粉等改性生物质吸附剂在去除和回收磷酸盐方面的最新研究进展,分析了对生物质材料进行改性以增加其表面官能团、提高比表面积和零点电荷的多种途径;讨论了改性生物质吸附剂对磷酸盐的吸附机制、影响吸附量的各种因素以及磷酸盐的回收方法。与未改性的吸附剂相比,改性后的生物质吸附剂对磷酸盐的吸附能力显著提高;未来应重点研究如何进一步提高生物质材料对磷酸盐的吸附量、吸附剂的可重复利用性以及水环境适用性。     

生物炭/凹凸棒土的制备及对磺胺嘧啶的吸附

利用凹凸棒土（ATP）和碱性木质素（AL）慢速限氧热解制备生物炭/凹凸棒土（BC/ATP）吸附水中的磺胺嘧啶（SDZ）,研究原料比例和热解温度对产品组分含量和吸附效果的影响,并探讨初始pH、BC/ATP投加量、吸附时间和SDZ初始浓度等因素对去除率的影响。分别采用拟一级、拟二级和颗粒内扩散方程拟合吸附过程动力学,用Langmuir和Freundlich方程拟合等温吸附线。通过扫描电镜、傅里叶红外光谱、X射线衍射、拉曼光谱和比表面积测定分析BC/ATP的表面形貌、孔结构和官能团。结果表明ATP能有效促进热解过程中挥发性中间产物二次热解,提高BC得率,改善BC/ATP吸附性能,并通过ATP的金属离子作用扩宽BC/ATP的pH敏感度。吸附动力学均符合拟二级动力学模型,且由颗粒内扩散模型拟合说明该扩散行为不是限制吸附速率的唯一因素,等温吸附线更符合Langmuir等温吸附模型,0＜R_L＜1,为优惠吸附,说明吸附过程易于进行,最大吸附量为109.53mg/g。不同pH条件下吸附机理可分为两部分：①在酸性和中性条件下,主要依靠BC/ATP的上BC表面负电荷与SDZ静电作用;②碱性条件下主要依靠ATP表面金属离子与SDZ氢键的金属阳离子桥接作用。     

新型除氟吸附材料的研究进展

半导体、稀土开采等行业所排放的氟废水所引发氟中毒现象备受关注。吸附法是去除废水中氟离子的有效方法之一,但传统吸附剂存在吸附容量低、选择性差等缺点,亟需研发具有高吸附容量、可再生且无二次污染的吸附材料。本文归纳了一些新型吸附材料,如高分子材料吸附剂、生物炭、层状双氢氧化物、工业废弃物、纳米材料及其改性材料在含氟废水中的研究应用;总结了这些改性材料的制备过程,介绍了这些材料吸附除氟的能力,分析了新型吸附材料吸附除氟的机理以及共存离子干扰、pH适用范围等影响因素,并指出了材料制备存在的问题,提出了制备对氟离子具有高选择性能的改性吸附材料的发展方向和材料循环利用所需解决的重要问题。     

磁性壳聚糖微球吸附剂的研究进展

随着现代工业的迅速发展,生产过程中排出的有害重金属离子废水、印染废水等日益增加,寻找更为高效的水处理材料成为环境保护中亟待解决的问题。磁性壳聚糖微球是一种新兴的水处理吸附剂,对多种污染物都具有优良的吸附效果,再加上可回收重复利用的特点,受到了广泛关注。对磁性壳聚糖微球进行改性,可赋予它不同的功能特性。综述了不同交联剂制备磁性壳聚糖微球的研究现状,分别介绍了对壳聚糖外壳和Fe₃O₄磁核的改性方法、机理及其应用,并对磁性壳聚糖微球未来的研究趋势进行了展望。     

几种氯酚类污染物吸附剂的研究现状与展望

文章综述了氯酚类废水污染治理中几种吸附材料的研究现状,主要对活性炭、壳聚糖及改性壳聚糖、碳纳米管、微生物类吸附剂及分子印迹吸附剂等在含氯酚类废水中的突出特点和应用进行了分析和论述,指出开发低成本、无污染、选择性高、易分离的高效吸附剂是未来的发展方向。     

Highly dealuminated Y zeolite as efficient adsorbent for the hydrophobic fraction from wastewater treatment plants effluents

In this work we report that highly dealuminated zeolite Y is a hydrophobic material that is able to remove selectively fatty acids and hydrocarbon compounds from the effluent of an urban wastewater treatment plant (UWTP). This adsorbent capability of zeolite Y could lead to an improved quality of UWTP effluents. Typical domestic wastewaters contain detergents, soaps and surfactants that are only partially removed in conventional UWTP. In the present work using an effluent from a UWTP located at Ribarroja del Turia (Valencia, Spain) containing 10 ppm of total organic carbon, we have been able to retain by adsorption on the dealuminated Y zeolite up to 16 and 60% of the organic matter of the effluent at pH values 7.2 and 4, respectively. Characterization of the adsorbed organic matter by Fourier transformed infrared (FT-IR), ¹H NMR and GC–MS after derivatization has shown that the zeolite adsorbs selectively the hydrophobic compounds of the effluent.     

Nitrogen adsorption on carbonaceous materials: A comparison between static and dynamic methods

The purpose of this study was to investigate the influence of the method of adsorption of N₂ at − 196 °C on the isotherm obtained for, and hence derived textural parameters of, a wide series of carbonaceous materials (CM). Two pyrolyzed products, six activated carbons and two carbon blacks were used. The carbonized products were prepared by pyrolysis of cherry stones at 600 or 900 °C in nitrogen atmosphere (P-600, P-900). Three activated carbons were made by activation of P-600 at 275 °C in air and of P-900 at 850 °C in carbon dioxide or steam, whereas the remaining CM were commercial products. The adsorption isotherms for N₂ at − 196 °C were determined by static and dynamic methods in Quantachrome equipments. The CM were further characterized texturally by means of mercury porosimetry and helium and mercury density measurements. Because of the presence of helium in the adsorptive gas stream, the adsorption of nitrogen noticeably decreases for the CM containing micropores obstructed with tarry products (i.e. P-600 and the activated carbon prepared from it by air activation). For the rest of the activated carbons the adsorption increases, as they must possess narrow micropores having easier access to N₂ at − 196 °C. Helium causes a decrease in the degree of interaction between the nitrogen molecules in the gas stream and as a result the diffusion of nitrogen in pores of the adsorbent increases. For the carbon blacks, however, helium hardly affects the adsorption of nitrogen, except for at high relative pressures of this gas. Helium also influences the capillary condensation phenomenon occurring in mesopores. The variation percentages in the micro- and mesopore volumes are as high as 20 and 50, respectively. Such percentages as a rule are higher for the activated carbons.