吸附材料再生方法的研究现状及发展趋势

再生是处理吸附材料的有效途径,具有重要的研究意义。对几种典型的再生方法,如热再生、湿式氧化再生、溶剂再生等的研究概况进行了综述。重点阐述了再生机理、再生方法的优缺点,并对吸附材料再生方法的发展趋势进行了展望。     

吸附材料电化学再生的研究进展

随着吸附材料用量的与日俱增,其后处理成为重要研究课题。作为一种新型的再生技术,电化学再生可有效地处理废吸附材料。本文阐述了电化学再生机理,探讨了影响电化学再生的主要因素。通过电化学再生与传统的热再生和溶剂再生的比较分析,总结了电化学再生技术的优劣势。最后对电化学再生技术的发展方向和趋势做了展望。     

吸附材料超声波再生的研究进展

超声波再生是处理吸附材料的有效途径之一。介绍了超声波再生技术的原理,分析了影响超声波再生吸附材料效率的主要因素。通过对超声波再生与传统的热再生的比较,探讨了超声波再生的优势与劣势,并对超生波再生技术的发展方向和趋势做了展望。     

石墨烯及其复合材料在重金属离子吸附方面的应用

重金属污染是目前最为严峻的环境污染问题之一,因此,寻找高效的纳米材料去除水中的重金属变的尤为重要。作为碳系家族的新成员,石墨烯已经成为万众瞩目的研究热点。由于具有超大的比表面积、较高的机械强度和稳定的化学性质等突出优势,石墨烯不仅在场效应晶体管、催化、药物输送等领域应用前景广阔,而且作为吸附材料在重金属离子处理方面的潜能也备受关注。综述了近年来有关石墨烯及其复合材料吸附水溶液中重金属离子的研究,系统介绍了石墨烯基材料对重金属离子的吸附效果、吸附机理、影响因素,及该材料的脱附再生性能。最后,对石墨烯及其复合材料研究过程中的挑战进行了评述,同时对它们在水处理过程中的应用前景做了深入探讨和展望。     

纳米纤维素材料在重金属废水治理中的应用

纤维素是自然界中来源最广泛的天然高分子材料,近年来引起了能源、环境和材料等领域研究者的广泛关注。结合可再生生物质材料与纳米科技制备的纳米纤维素基重金属吸附材料具有可降解、可再生、环境相容性好、吸附量大、可选择性吸附等优势,是重金属治理技术重要的研究方向。然而,天然纳米纤维素在水体中会存在大量由羟基形成的氢键,导致材料的吸附容量降低、特异性吸附能力削弱。为此,一方面可以在制备纳米纤维素吸附材料时通过化学改性、酶化处理等手段引入活性基团或金属氧化物,提高材料分散性、特异性吸附性能和吸附容量等。另一方面,可将纳米纤维素与天然矿物、有机材料、氧化石墨烯等复合,制备高性能复合材料。纳米纤维素材料的化学改性研究相对成熟,但是酶法处理研究仍然处于起步阶段,目前有限的研究主要关注特定酶处理的反应进程及产物,缺乏多重适应性和工程应用性分析。在实际应用中,纳米纤维素除了直接制备粉末吸附剂外,往往制备成凝胶材料、杂化或复合材料等,或者进一步加工成纳滤膜、滤纸和过滤器等净水材料。基于此,本文从制备技术、吸附机理、改性强化和应用形式等角度简要介绍纳米纤维素基重金属吸附材料的最新研究进展,重点讨论纳米纤维素吸附材...     

活性炭对VOCs的吸附研究进展

挥发性有机化合物(VOCs)是大气主要污染物之一,包括烃类化合物和芳香族化合物,如乙二醇和苯等.VOCs不仅导致温室效应,破坏臭氧层,而且当其浓度偏高时,会引起人体不适,严重时危及生命,因此如何有效地处理VOCs成为学术界和工业界的研究热点.目前,处理VOCs的技术众多,包括催化氧化等破坏性回收技术和吸附等可恢复性技术.相比于在回收过程中不可避免会产生有毒副产物的破坏性回收技术,吸附技术具有VOCs回收效率高、操作简单、能量消耗低等优点,因而被广泛应用.吸附技术的核心是吸附剂.活性炭因具有较高的比表面积、良好的孔道结构以及易于表面官能团改性等优点,被认为是一种具有潜力的VOCs吸附材料.但目前未经改性的活性炭通常比表面积小、表面官能团含量少、对VOCs的吸附能力和选择性较差且疏水能力差,极大地影响了其在潮湿环境中的应用.鉴于此,本文在介绍活性炭对VOCs吸附和脱附原理的基础上,从活性炭的物理结构和表面化学性质两个角度出发,重点介绍不同改性方法(物理改性、化学改性等)改性后的活性炭对VOCs吸附能力和选择性的影响,并对吸附饱和后活性炭的再生方法进行总结.本文旨在系统总结活性炭对VOCs的吸附、解吸和再生机理,以及活性炭改性技术的最新进展,为制备比表面积大、表面官能团丰富的工业化活性炭提供参考.     

微波技术在吸附分离中的应用研究进展

在吸附分离过程中,微波技术主要应用于吸附材料的合成和吸/脱附过程的强化。采用微波合成吸附材料可提高能量利用率、大幅度缩短反应时间、产物均匀且吸附性能更优异。在吸附过程中,微波场通过促使极性分子转动加速体系传质过程,加快吸附;在脱附再生过程中,被吸附物质在微波场中被加热而发生挥发或者分解。微波强化的作用机理以及微波场中体系温度的准确测量和控制有待进一步研究。     

金属-有机框架材料对废水中污染物的吸附研究进展

可用的清洁水资源缩减已成为全球面临的重要危机.引起该危机的主要原因是各种污染物因生产、生活或事故排入水体导致水体污染.因此,解决水资源危机的关键在于对污水处理和再生.多种污水处理和再生方法应运而生,其中吸附法因处理效率高、操作简便、成本低而被广泛应用到污水处理中.吸附法的关键在于吸附剂的选择和应用.应用于水处理的传统吸附剂,如活性炭、沸石、天然粘土、活性氧化铝等,在面对复杂水体环境和各种性质迥异的污染物时已不能符合水污染处理的更高标准.因此,新型吸附剂的开发与应用成为吸附领域研究热点.金属有机框架(Metal-organic frame,MOF)材料,一类金属离子或金属簇与有机配体之间自组装配位形成的化合物,具有高比表面积、高孔隙率和可控的孔结构,已成为吸附领域冉冉升起的新星.目前MOF材料作为水处理吸附剂的研究主要集中在:(1)各种MOF材料对不同污染物的吸附性能研究,以揭示相关吸附规律;(2)MOF材料自身功能化或MOF复合材料的制备,以改善自身稳定性,提高其吸附性能或实现选择性吸附;(3)MOF衍生碳吸附材料的研究,以应对恶劣水体环境或极端水处理条件.本文对单一MOF材料、功能化MOF材料、MOF衍生碳材料吸附去除水体中有机染料、其他有机污染物、重金属离子的相关研究进行了综述.概述了多种MOF材料对不同污染物的吸附性能,总结了针对吸附应用的多种MOF功能化方式及其吸附效果的改进,归纳了多种MOF衍生碳材料作为吸附剂在水处理中的应用,指出了目前MOF吸附材料在水处理中存在的主要问题,并提出了解决这些问题的思路.     

超声波法对吸附Ni(Ⅱ)吸附剂的再生

目前,有关超声波对有机改性凹凸棒黏土吸附剂的再生研究不多。研究了有机改性凹凸棒黏土吸附剂吸附Ni(Ⅱ)后,在超声波作用下再生后吸附Ni(Ⅱ)的效果及其与再生各因素的关系,分析了超声波对吸附剂的再生机理。结果表明:用超声波法对有机改性凹凸棒黏土吸附剂进行再生,在超声波频率40 Hz、功率500 W的条件下,最佳再生温度为45℃,最佳再生时间为1 min,最佳再生pH值为6,最佳再生固液比为7 g/L。吸附剂再生5次后,仍有较好的吸附效果。     

水热合成钛酸盐纳米材料吸附水中放射性核素研究进展

钛酸盐纳米材料因其原材料储量较多、来源广泛,合成方法较为简单,表面离子交换位点多等特点被用作水中放射性核素离子的吸附材料。综述了材料的水热合成方法与钛酸盐纳米管的形成机理,总结了材料对水中放射性核素的吸附效果、机理、影响因素等一系列研究进展。展望了材料的水热合成方法、改性方法在未来的研究发展方向与实际应用前景。     

石墨烯基吸附剂的特性、吸附原理、改性复合及 研究方法

石墨烯具有独特的结构和优异性能,适合用作水处理吸附材料。介绍了与吸附相关的石墨烯的结构及特性,石墨烯基材料对不同污染物的吸附原理;基于石墨烯的性质和结构特点,对石墨烯基材料的改性、复合方法及其研究方法作了较详细论述。鉴于石墨烯基材料再生性能的重要性,对磁性石墨烯及三维石墨烯吸附材料作了简单介绍,最后对石墨烯基吸附剂研究的发展方向作了展望。     

Progress in the Physisorption Characterization of Nanoporous Gas Storage Materials

Assessing the adsorption properties of nanoporous materials and determining their structural characterization is critical for progressing the use of such materials for many applications, including gas storage. Gas adsorption can be used for this characterization because it assesses a broad range of pore sizes, from micropore to mesopore. In the past 20 years, key developments have been achieved both in the knowledge of the adsorption and phase behavior of fluids in ordered nanoporous materials and in the creation and advancement of state-of-the-art approaches based on statistical mechanics, such as molecular simulation and density functional theory. Together with high-resolution experimental procedures for the adsorption of subcritical and supercritical fluids, this has led to significant advances in physical adsorption textural characterization. In this short, selective review paper, we discuss a few important and central features of the underlying adsorption mechanisms of fluids in a variety of nanoporous materials with well-defined pore structure. The significance of these features for advancing physical adsorption characterization and gas storage applications is also discussed.     

Assessment of adsorption-desorption characteristics of adsorbents for adsorptive desiccant cooling system

The performance of various dehumidification materials was assessed in terms of effective adsorption amount of water vapor based on the adsorption isotherms to find a suitable dehumidification element for an economical adsorptive desiccant cooling system being developed. The effective adsorption amount is an important factor for regeneration at lower temperatures. Three types of silica gels, S(a), S(b), and S(c), with different pore volumes and pore size distributions, and zeolite with various molar ratios of Si/Al, 5.6, 29, 47, 91, and 220, prepared from a Y-type zeolite treated with hydrochloric acid, an activated carbon with silica gel added to improve the hydrophobic surface, and MCM-41 were examined. Silica gels having effective adsorption amounts of 0.25 g/g, and activated carbon with silica gel added were assessed to be candidate desiccant materials.     

Mesoporous hydroxyapatite by hard templating of silica and carbon foams for protein release

Calcium phosphates, particularly hydroxyapatite Ca₁₀(PO₄)₆(OH)₂ (HA), are widely used for bone regeneration due to their biocompatibility and good resorption properties. However, their performance upon implantation is improved when they are associated with bioactive molecules such as growth factors. Using mesoporous HA leads to improved protein adsorption and release kinetics because the diameter of the mesopores (2–50 nm) is in the same range as their size. We prepared this type of material by the nanocasting method using three different templates: a silica foam and two carbon templates derived from it using propylene or sucrose as carbon source. We investigated the influence of the template, the calcination temperature and of the conditions during template removal. We obtained HA materials with a surface area of up to 90 m² g^?1 and with an intergranular mesopore volume of up to 0.4 cm³ g^?1. In this paper, we show for the first time that the synthesis of mesoporous HA from a mesoporous silica foam template allows eliminating the template at lower temperatures (in an alkaline medium), thus preventing the sintering of the HA. These materials have interesting properties for drug delivery applications. The protein adsorption and release capacities of these HAs were tested with two model proteins, bovine serum albumin (BSA), and Cytochrome C. These materials are an important milestone for future bone regeneration systems based on HA associated with human growth factor proteins.     

固定吸附床结构对再生和除湿效果的影响

介绍了一种在固定床内通入DN20水管的固定床结构。实验以硅胶为固体吸附材料,向水管中通入不同温度的水,对固定床进行三组实验,利用除湿量、吸附量、吸附能效三个评价指标分析了三组实验的再生能力和吸附效果。结果表明:实验1是再生和吸附效果最佳的一组实验,实验1的解析量是实验2的1.36倍,是实验3的1.12倍;实验1的除湿量是实验2的1.16倍,是实验3的1.17倍。     

体外模拟胶原纤维矿化的研究进展

矿化胶原纤维是天然骨的主要成分,掌握胶原纤维的生物矿化过程、原理和调控机制对于骨修复材料的设计及骨组织的再生修复发展有重要意义。综述了体外模拟胶原纤维矿化的研究进展,主要包括胶原纤维内矿化机理和非胶原蛋白对胶原生物矿化的调控作用,以期为胶原生物矿化机理的探讨及骨组织再生修复的研究提供借鉴。     

Organ regeneration: integration application of cell encapsulation and 3D bioprinting

3D bioprinting has shown great promise in the field of tissue engineering, which offers a vital and significant platform for organ regeneration. Therefore, an increasing focus on 3D bioprinting, coupled with a growing knowledge of cell–cell interaction and cell encapsulation, has driven researchers to discover the preferable biomaterials that enable the greatest possible to reconstruct artificial organs with the different cells and hydrogel. One important challenge is to adapt materials selected to improve the cell survival rate. In this paper, we firstly summarise the fundamentals and the latest application of biomaterials that have significant characteristics such as porous, biodegradability, biological compatibility, and adaptability, and further describe formation mechanisms of droplet under the different cell encapsulation technologies, and finally highlight integration application of cell encapsulation and 3D bioprinting.     

Surface-modified mesoporous silicas as recyclable adsorbents of an endocrine disrupter, bisphenol A

Surface-modified mesoporous silicas (MSs) were investigated for recyclable adsorption of an endocrine disrupter, bisphenol A (BPA). Surface-modified MSs were prepared by (i) post-synthesis surface modification of MSs using surface hydroxyl groups and organosilanes (m-MS) and by (ii) co-condensation of tetraethoxysilane and the corresponding organosilanes (d-MS). Infrared measurements indicated that organic groups mainly existed on the surface of m-MS, which resulted in a surface characterized by high hydrophobicity. Both organic groups and isolated hydroxyl groups existed on the surface of d-MS, resulting in both hydrophobicity and hydrophilicity on the surface. The amount of BPA adsorbed on surface-modified MSs per organic group was similar for m-MS and d-MS, however, the d-MS established equilibrium for BPA adsorption faster than m-MS, as measured by UV-vis spectra. A larger amount of BPA per surface area could be adsorbed on carbon materials than on the surface-modified MSs, however, the regeneration of carbon materials by washing could not be done easily. The surface-modified MSs retain adsorption capacity for BPA after several regeneration cycles, demonstrating that the surface-modified MSs are effective recyclable adsorbents of the endocrine disrupter, bisphenol A.     

金属基吸附剂及其复合材料吸附除氟研究进展

化工、冶炼、电池等行业所排放的氟废水引发的氟中毒现象备受关注,分析了沉淀、膜处理、离子交换、吸附等技术的优缺点,吸附法由于操作简单、经济高效被认为是极具前景的水体除氟方法。本文对铝基、铁基、稀土基、金属有机骨架吸附剂及其改性材料在含氟废水中的除氟性能进行了总结和评价,分析了其制备过程、脱氟机制以及外界影响因素。发现材料晶型可以决定吸附过程的吸附能,大的比表面积可以在吸附过程中提供更多的活性位点,良好的孔结构可以降低吸附传质阻力,提高吸附性能;材料表面官能团的强化、不同金属材料的复合协同作用可以提高吸附剂的脱氟效率,可为今后制备新型高效除氟材料提供参考。提出了目前吸附除氟领域亟待解决的问题并对金属基吸附剂在除氟领域的发展作出展望。