三维超浸润多孔材料在油水分离中的研究进展

受自然界超浸润现象的启发,三维超浸润多孔材料因其具有独特的油水分离优势受到科研工作者的广泛关注。本文首先分析了三维超浸润多孔油水分离材料的表面浸润性基础模型,包括Young模型、Wenzel模型和Cassie-Baxter模型;随后指出设计三维超浸润多孔材料的关键是调控材料的表面能和纳微结构,总结了三维超浸润多孔材料存在的独特优势,包括空隙率高、密度小、质地轻、比表面积大等特性;揭示了常见的三维超浸润多孔材料的油水分离原理,包括表面介质或基团对油滴/水滴的吸附效应以及不同亲疏性的选择效应。基于此,概括了不同种类三维超浸润多孔材料在油水分离领域中的研究进展,包括三维超浸润多孔海绵、三维超浸润多孔泡沫、三维超浸润多孔气凝胶,并针对不同类型三维超浸润多孔材料在油水分离过程中存在的独特优势和缺陷进行了总结,指出三维超浸润多孔材料在实际应用中存在的问题和挑战,并对研究出机械性能稳定、回弹性好、具备持久分离效果的三维超浸润多孔材料进行了展望。     

宁波材料所制备出高效油水分离用纤维素海绵

<正>近年来,超疏油-超亲水材料由于其特殊的润湿性在油水分离方面备受青睐。由于"油"的表面张力远小于水,故超疏油-超亲水表面较难制备而且超疏油表面大多超疏水,这就限制了其在油水分离方面的应用。此外,表面活性剂稳定的乳化油油滴粒径小(10μm)、稳定性高,需要复杂的破乳过程才能实现油水分离。所以,亟需一种简单、高效、环境友好的油水分离材料来实现含油污水的净化处理。中国科学院宁波材料技术与工程研究所科研人员曾志翔、王刚、贺怡等通过纤维素的溶解再生及成孔剂     

疏水性油水分离膜及其过程研究进展

油水分离是治理含油废水和含水油液的重要工业过程。本文概括了疏水性油水分离膜的类型与制备方法,包括常规分离膜和高度疏水/超亲油分离膜。前者为常规微滤、超滤及纳滤过程用膜;后者由构筑高度疏水（水滴接触角≥120°）表面方法得到,形式有金属网膜、纤维膜、滤纸、复合膜及不对称膜,其为制备耐污染的疏水性油水分离膜提供了新思路。指出了疏水性膜用于油水分离的过程原理及应用现状：含油废水除油中,疏水性膜可实现O/W乳液的破乳、粗粒化油滴、滤除油滴及吸附油分子几方面的功能;含水油液除水中,膜被用来截留水滴,可直接得到净化的油品。最后,指出了其过程规模化应用前尚需解决的重要问题,特别是高度疏水/超亲油分离膜的制备、相关过程研究的深入及其规模化试验等方面需着力加强。     

特殊润湿性吸附材料的油水分离研究进展

综述了超润湿性吸附材料在油水分离中的应用,分析了超疏水超亲油材料、超亲水水下超疏油材料或超亲水超疏油材料及转换润湿性的智能吸附材料的优缺点。经过对油水分离的操作方式、分离效率等方面的多方对比,提出了特殊润湿性吸附材料在油水分离方面存在的不足、改进方向和展望。     

超疏水材料在油水分离中的研究进展

石油工业产生的采出水对环境是一个重大的问题,也是对水资源的一种浪费。油田采出水中存在大量的油,为了保护环境和节约水资源,我们可以对其进行回收再利用。受到大自然的启发,仿生超疏水材料应用到了油水分离领域。在这篇综述中,主要关注在油水分离应用中超疏水材料的研究进展。基本上都是通过对表面化学成分和表面形貌之间的协同作用实现基材的超疏水特性。将超疏水材料根据其除油方式的不同分为超疏水过滤材料和超疏水吸附材料两大类,并分别展开详细的介绍了超疏水过滤材料的各种基材包括金属网、纺织物、聚合物膜等,超疏水吸附材料的各种基材如粉末颗粒、海绵泡沫、气凝胶等,简单的介绍了材料的制备方式,油水分离的效率以及各种材料的优势、劣势。最后总结了过滤材料和吸附材料在油水分离领域中存在的一些挑战,并对未来发展方向进行了展望。     

纳米材料在油水分离应用方面的研究进展

油水分离是当前处理处置各类含水工业废油,修复环境水体油液污染的关键技术;而纳米技术的快速发展已经在各个领域,包括能源、环境及医学等领域发挥着巨大的作用。利用纳米材料的特殊性质结合传统材料的特点制作超疏水-超亲油性、超亲水-超疏油材料用于油水分离是目前的研究热点之一,具有广阔的应用前景。综述了近几年来纳米材料在油水分离应用方面的研究进展,主要介绍了超疏水、超亲水、磁性等几种主要的纳米材料的制备,油水分离的效率,适用范围等。综述有望为开发高效的油水分离技术和设计新型分离材料提供技术参考。     

纳米材料在油水分离应用方面的研究进展

油水分离是当前处理处置各类含水工业废油,修复环境水体油液污染的关键技术;而纳米技术的快速发展已经在各个领域,包括能源、环境及医学等领域发挥着巨大的作用。利用纳米材料的特殊性质结合传统材料的特点制作超疏水-超亲油性、超亲水-超疏油材料用于油水分离是目前的研究热点之一,具有广阔的应用前景。综述了近几年来纳米材料在油水分离应用方面的研究进展,主要介绍了超疏水、超亲水、磁性等几种主要的纳米材料的制备,油水分离的效率,适用范围等。综述有望为开发高效的油水分离技术和设计新型分离材料提供技术参考。     

特殊润湿性表面的油水分离研究进展

以油水分离的材料表面润湿性为主线,介绍了特殊润湿性表面的制备机理,分析了超疏水超亲油、超亲水超亲油、超亲水超疏油、可转换润湿性的智能表面的优缺点,提出了特殊润湿性材料在油水分离方面的改进方向。未来特殊润湿性材料表面必定向环保、低廉、多功能的方向发展。     

超疏水多孔材料的研究进展

多孔材料如金属有机框架材料(MOFs)、共价有机框架材料(COFs)、有机多孔聚合物(POPs)等由于构筑单元的多样性、可设计性,孔道的可调控性和功能化,已经被广泛用于分离、催化、气体储存以及药物释放等领域。尽管如此,这些多孔材料固有的结构特征让它们普遍对水气非常敏感,最严重时多孔结构在水溶液环境下会坍塌。为解决此类问题,制备疏水的多孔材料是一个非常好的策略。然而,设计超疏水多孔材料具有一定的挑战。介绍了具有(超)疏水性能的MOFs、COFs和POPs的发展现状,对超疏水多孔材料合成思路和结构特点进行了分析,对这类材料在催化、油水分离、气体吸附和分离等方面的应用进行了总结,并进一步探讨了此类材料存在的问题和发展方向。     

纳米膜材料在井下油水分离中的研究

近年来,由于油井产出水逐年增多,举升、处理及环保等问题日益严重,为了解决上述问题,技术人员开发出井下油水分离技术.虽然机械旋流分离的方式可实现回注水含油率指标1000μg·g-1,但在恶劣工况下可能达到3000μg·g-1,不能满足回注水指标要求.研究发现,基于特殊润湿性材料对油和水的选择性作用,制造出亲水膜和亲油膜材料,通过控制表面的形貌结构和化学性质来调控表面润湿性,实现油和水的分离.通过研究,利用泡沫镍疏水改性成功制备出超亲油疏水材料,通过室内实验与数值模拟,分离效果和机械性能满足井下环境要求.采用井下机械旋流分离与超亲水、疏水材料相结合的井下纳米油水分离更大幅度地降低回注水中含油率,成为井下油水高效分离的新方向.     

仿生超疏水金属材料制备技术及在化工领域应用进展

超疏水表面是材料研究热点,而超疏水金属材料在化工领域应用前景广阔。本文对超疏水金属表面材料在制备方法和实际应用的最新进展进行了综述,在浸润模型基础上,重点概括了针对金属构建微纳粗糙结构用于超疏水表面制备的方法,并对包括自清洁、流动减阻、强化换热、抗结冰、金属防腐、油水分离等常见化工领域应用以及新开发的如防垢、滚动造粒、蒸发结晶等新应用方向的最新相关研究成果进行了总结,并提出了规模化绿色廉价快速一步制备稳定高效超疏水金属表面是未来研究趋势。     

Robust graphene/poly(vinyl alcohol) aerogel for high-flux and high-purity separation of water-in-oil emulsion and its computational fluid dynamic simulation

Due to the trade-off between purity and flux, the development of high-purity, high-flux oil–water separation materials is still an arduous challenge. Herein, to achieve emulsion separation with high purity and high permeability, fluorinated graphene/poly(vinyl alcohol) aerogel (FGPA) with strong honeycomb was obtained via a facile freeze-drying method, and the separation mechanism was investigated via computational fluid dynamics (CFDs) simulation. The as-prepared FGPA exhibited superhydrophobicity-superoleophobicity and cyclic compression stability. Under the complex pore and superhydrophobicity, FGPA could separate water-in-oil emulsions with droplet sizes several times smaller than their own aperture only under gravity with ultrahigh flux (3255 L m⁻² h⁻¹) and ultrahigh purity (99.9%). Also, the separation process as visualized using simulations revealed that the vortex accelerates the demulsification behavior and promotes the gathering of water droplets rebounding on the superhydrophobic surface, so that the water droplets are intercepted. Therefore, FGPA has broad practical application potential in high-flux and high-purity oil–water emulsion separation.     

Facile and Eco-Friendly Fabrication of Multifunctional Melamine Sponge for Labeled Cr(VI) Removal and Highly Efficient Oil/Water Separation

Fabrication of multifunctional adsorbent of single-phase material is quite challenging and meaningful for water treatment. In this work, a polyaminosiloxane functionalized melamine sponge is used to remove both heavy metal ions and oil from water. Benefiting from its porous structure, superhydrophobic surface, and abundant amino groups on the surface, the sponge shows excellent performance in Cr(VI) removal and oil/water separation. Notably, the sponge exhibits fluorescent detection function for Cr(VI) owing to the packing of Schiff-base bonds, facilitating the adsorption process to be monitored in real time. The maximum adsorption capacity of Cr(VI) is 252.82 mg g⁻¹ with good selectivity. In addition to the excellent Cr(VI) removal performance, its superhydrophobic nature allows it to adsorb 92.42 times the weight of oil and realize 99.97% oil/water separation efficiency. This trifunctional cost-effective adsorption material shows great potential for large-scale water purification application.     

Application of magnetic nanoparticles as demulsifiers for surfactant-enhanced oil recovery

Nonionic surfactants are increasingly being applied in oil recovery processes due to their stability and low adsorption onto mineral surfaces. However, these surfactants lead to the production of emulsified oil that is extremely stable and difficult to separate by conventional methods. This research characterizes the stability of crude oil mixed with a nonionic surfactant, L24–22, in a brine solution. When subjected to gravity separation, a middle oil-rich and bottom water-rich emulsion are generated for various water–oil ratios. Thermal treatments can effectively break oil-rich emulsions, but the bottom water layer remains contaminated with micron-sized crude oil droplets. A magnetic nanoparticle treatment is shown to demulsify the crude oil emulsions, dropping the total organic carbon (TOC) in the water layer from 1470 to 30 ppm.     

超疏水抗菌表面的研究进展

超疏水抗菌表面将疏水材料的特殊浸润性能与抗菌材料的优异杀菌性能结合,通过"双重保险"实现建筑、器械、织物等多种材料表面的长久抗菌,对保护人们身体健康及延长材料使用具有重要的作用.该文介绍了无机、有机、无机-有机三类超疏水抗菌表面的制备方法,综述了其在油水分离、涂层防污、医疗卫生应用领域的研究进展,最后对超疏水抗菌表面的发展进行了展望.     

二甲苯吸附剂及其在泄漏事故水域的适用性评述

二甲苯是泄漏事故频率较高的一种典型危险化学品。在化学品泄漏响应中，吸附材料可以作为一种资源用于水中化学品的回收。为了选择一种优秀的吸附材料清除水面泄漏二甲苯，本文在介绍5类吸附剂（矿物类、生物质、纳米材料、有机合成化合物和超疏水材料）的结构特点、吸附原理、吸附性能基础上，评述了各类吸附剂应用于泄漏事故水域二甲苯分离去除的优缺点，介绍了各类材料吸附分离二甲苯的最新进展。分析表明，超疏水三维多孔材料（超疏水海绵、超疏水纤维等）和超疏水网膜材料由于具有较高的亲油疏水性和二甲苯吸附容量，且机械强度大、耐磨性强、再生方法简单，使其适于作为大面积二甲苯污染水域的分离材料。本文对改进超疏水材料应用效果提出了建议。     

The performance of superhydrophobic and superoleophilic carbon nanotube meshes in water–oil filtration

Vertically-aligned multi-walled carbon nanotubes (CNTs) were grown on stainless steel (SS) mesh by thermal chemical vapor deposition with a diffusion barrier of Al₂O₃ film. These three-dimensional porous structures (SS-CNT meshes) were found to be superhydrophobic and superoleophilic. Water advancing contact angles of 145–150° were determined for these SS-CNT meshes in air and oil (gasoline, isooctane). Oil, on the other hand, completely wet the SS-CNT meshes. This combined superhydrophobic and superoleophilic property repelled water while allowed the permeation of oil. Filtration tests demonstrated efficiencies better than 80% of these SS-CNT meshes as the filtration membranes of the water-in-oil emulsions. We have conducted quantitative analysis on the diameters of the oil droplets in both the feed emulsion and the filtrate. Then, we have evaluated the issue of water blockage and possible way to improve the filtration efficiency. Finally, the filtration and blockage mechanisms are proposed.     

Under‐Oil Superhydrophilic Poly(vinyl alcohol)/Silica Hybrid Nanofibrous Aerogel for Gravity‐Driven Separation of Surfactant‐Stabilized Water‐in‐Oil Emulsions

For efficient and green separation of surfactant‐stabilized water‐in‐oil (W/O) emulsions, under‐oil superhydrophilic poly(vinyl alcohol) (PVA)/silica hybrid nanofibrous aerogel is fabricated by freeze‐drying the dispersion of shortened PVA/tetraethyl orthosilicate composite electrospun nanofibers in t‐butanol, followed by heat‐treatment. Its hierarchical porous structure, observed by scanning electron microscope, consists of major and minor pores with an average diameter of 15.9 and 1.0 µm, respectively. The silica‐based crosslinking structure inside the nanofibers and the chemical linkage between them, evidenced by infrared spectroscopy, endows the nanofibrous aerogel with desirable stability in water and compression recoverability. When it is used for gravity‐driven separation of Span80 stabilized water‐in‐n‐hexane emulsion, the flux is 2083 L m^?2 h^?1 and the purity of the separated n‐hexane reaches 99.997%, corresponding to the separation efficiency of 99.79%. The nanofibrous aerogel after use is readily recycled by rinsing and freeze‐drying, without using any organic solvent, as it possesses under‐oil superhydrophilicity and prominent oil antifouling property. Differing from the previously reported separation materials, PVA/silica hybrid nanofibrous aerogel simultaneously acts as gravity‐driven filtration material and adsorption material to both absorb their coalesced water droplets and allow the separated oil to penetrate in the separation process.