吸附材料吸附分离天然气中二氧化碳的研究进展

列举了目前分离天然气中的二氧化碳的3种典型研究方法,包括吸附法、吸收法和膜分离法,认为吸附分离法具有能耗低、稳定性强、再生性能好、操作弹性大、无腐蚀、不产生二次污染且分离效果好等优点,在脱除天然气中二氧化碳领域有着广泛应用。对几种不同类型的吸附材料进行了详细的介绍,综述了活性炭、硅胶、介孔材料、金属有机骨架材料(MOF)和沸石分子筛等几种常用吸附剂的国内外研究进展,并对其吸附二氧化碳的效果进行分析,同时指出开发高效廉价、物理化学性质稳定、吸附能力强、选择性好的吸附剂是今后研究的主要方向。     

胺功能化介孔二氧化硅捕集CO2的研究进展

胺功能化介孔二氧化硅因其高选择性、高吸附容量、快速的吸附动力学、良好的再生性能和循环稳定性受到广泛关注,在二氧化碳捕集技术中具有优良的应用前景。本文比较了胺改性的M41S、SBA-n、KIT-n、介孔二氧化硅泡沫、介孔二氧化硅纳米球和六方介孔二氧化硅的吸附性能,总结了MCM-41和SBA-15的结构特点。介绍了胺化合物的负载方式——湿法浸渍、化学接枝和原位聚合的胺负载原理。分析了硅源、载体内部性质、气体选择性和不同添加剂对胺功能化介孔二氧化硅材料吸附二氧化碳能力的影响。最后,点明了吸附剂未来的发展目标,对胺功能化介孔二氧化硅材料的研究方向进行了展望。指出未来可关注介孔二氧化硅微观结构和温度对胺与二氧化碳相互作用的影响,增强胺功能化介孔二氧化硅的稳定性,推进其在实际环境下的应用。     

用于二氧化碳捕集的固体吸附材料研究进展

过量的二氧化碳气体排放造成了全球变暖,二氧化碳的捕集与封存(CCS)势在必行。与传统的液体胺吸附技术相比,固体吸附材料有吸附量高、再生能耗小、循环稳定性好等优点。本文主要介绍了一些典型的二氧化碳多孔吸附材料,如碳基材料、沸石、介孔二氧化硅、MOFs、胺基负载材料等的结构特点及研究进展。     

液化天然气脱水过程中固体吸附剂的选择

在一定压力与温度下,天然气中的饱和水汽一般无法通过分离器脱除。因此,必须采用适当的脱水工艺,液化天然气的常用脱水方法主要包括冷却分离法、溶剂吸收脱水法、固体吸附脱水法与膜法脱水法。其中固体吸附脱水法是较常用的方法,常用的固体吸附剂有硅胶、活性氧化铝、4A和5A分子筛。分析几种固体吸附剂的性能,建议采用分子筛进行脱水。     

无机固体吸附剂在二氧化碳捕集应用中的研究进展

随着全球气候变暖,二氧化碳的捕集、利用和封存（CCUS）逐渐成为科学界和工业界的研究热点。CCUS的关键是选择性地从气体混合物中捕集二氧化碳。目前二氧化碳捕集技术包括化学吸收、膜分离、吸附和低温分离等。吸附法是利用吸附剂对不同气体的吸附能力差异来进行二氧化碳捕集。综述了分子筛、介孔二氧化硅、黏土及多孔碳等无机固体吸附剂在二氧化碳捕集应用中的研究进展。对比了不同改性方法对吸附剂吸附二氧化碳性能的影响。从应用角度来看,分子筛、介孔二氧化硅、黏土具有潜在的成本效益,但仍需在工程设计开发方面得以进一步发展,以适用于不同应用需求的二氧化碳捕集。     

HYSYS动态减压模块在天然气分子筛脱水塔升降压孔板计算中的应用

天然气脱水是天然气净化过程中必不可少的环节,选择合适的脱水技术和工艺是非常必要的。固体吸附法是天然气深度脱水工艺中最常用的一种工艺。天然气分子筛塔的再生操作中,升降压孔板流量的选取直接决定了分子筛床层的稳定和安全。使用HYSYS动态减压模块模拟计算天然气分子筛塔升降压孔板的流量。并对升降压孔板流量的稳态和动态计算结果进行了对比。     

介孔金属有机框架材料吸附水中重金属离子研究进展

介孔金属有机框架材料（介孔MOFs）相较于传统吸附剂具有孔径大、孔隙率可调、比表面积大、官能团丰富,便于功能化改性修饰等优点,可高效地吸附水体中重金属污染物。本文介绍介孔MOFs的特性、合成策略及四种合成介孔MOFs的方法,重点分析四种方法的介孔形成机理及其所面临的问题,并将四种合成方法的优劣进行了比较。详述介孔MOFs吸附去除水中重金属离子、类重金属阴离子以及放射性金属离子的研究进展;介绍了介孔MOFs在吸附去除重金属离子方面的可重复利用性;阐述介孔MOFs吸附去除水中重金属污染物的作用机理。对介孔MOFs成本高昂、合成条件苛刻、回收利用难等问题提出了优化方向,指出提高介孔MOFs的水稳定性、易回收利用、简便绿色合成技术以及痕量去除将是未来的研究方向。     

有机胺改性多孔材料制备固体胺二氧化碳吸附剂的研究进展

人类社会排放的温室气体逐年增多,全球变暖问题日益严重,二氧化碳减排已迫在眉睫。有机胺改性多孔材料制备的固体胺吸附剂,二氧化碳吸附性能十分优越,具有良好的工业应用前景。本文综述了介孔分子筛、硅胶、多孔炭材料等多种多孔材料载体负载有机胺制备固体胺吸附剂的方法,分析了其二氧化碳吸附性能,讨论了多孔材料的孔结构对吸附剂吸附性能的影响。     

车用燃料油固体脱硫吸附剂的研究进展

吸附脱硫的优势是投资成本低、操作条件温和,其技术关键在于研发吸附硫容量大、选择性高和再生性能好的固体吸附剂。本文综述了车用燃料油固体脱硫吸附剂的研究进展,包括常规的分子筛、活性炭、金属氧化物吸附剂以及一种新型金属-有机骨架（MOFs）材料脱硫吸附剂。从吸附机理、制备方法、脱硫效果等方面分析了上述吸附剂的优缺点和改进方向。提出今后的固体脱硫吸附剂可从吸附机理出发在分子尺度上设计和组装新材料的观点。     

金属有机框架材料在天然气纯化和存储领域的应用

金属有机框架材料（Metal-organic frameworks,MOFs）因其优异的孔道特性和灵活的结构可调性，作为新型吸附材料受到气体分离和存储领域的广泛关注。然而，在天然气的纯化和存储领域的使用需要对MOFs固体吸附剂进行系统的设计，简要论述了MOFs在天然气纯化过程中对二氧化碳和硫化氢两大杂质的分离，以期提高天然气的纯度，为高效的存储奠定基础，接下来，从吸附和解吸两个角度出发，论述利用MOFs进行天然气存储的考量因素。最后，总结了在天然气纯化和存储领域MOFs的设计合成思路以及MOFs吸附剂在稳定性、多功能性等方面所面临的挑战，以此提高MOFs吸附剂在未来推广使用的可能性。     

CO2 capture by amine-functionalized nanoporous materials: A review

Amine-functionalized nanoporous materials can be prepared by the incorporation of diverse organic amine moieties into the pore structures of a range of support materials, such as mesoporous silica and alumina, zeolite, carbon and metal organic frameworks (MOFs), either by direct functionalization or post-synthesis through physical impregnation or grafting. These hybrid materials have great potential for practical applications, such as dry adsorbents for post-combustion CO₂ capture, owing to their high CO₂ capture capacity, high capture selectivity towards CO₂ compared to other gases, and excellent stability. This paper summarizes the preparation methods and CO₂ capture performance based on the equilibrium CO₂ uptake of a range of amine-functionalized nanoporous materials.     

Rapid adsorption of alcohol biofuels by high surface area mesoporous carbons

Surfactant templated mesoporous carbons were evaluated as biofuel adsorbents through characterization of equilibrium and kinetic behavior for both ethanol and n-butanol. Variations in synthetic conditions enabled facile tuning of specific surface area (500-1300 m²/g) and pore morphology (hexagonally packed cylindrical or BCC spherical pores). n-Butanol was more effectively adsorbed than ethanol for all mesoporous carbons, suggesting a mechanism of hydrophobic adsorption. The adsorbed alcohol capacity increased with elevated specific surface area of the adsorbents, irrespective of pore morphology. While adsorption capacity of these mesoporous carbons is comparable to commercially-available, hydrophobic polymer adsorbents of similar surface area, the pore morphology and structure of mesoporous carbons greatly influenced adsorption rates, enhancing them by up to 1-2 orders of magnitude over commercial polymer adsorbents. Multiple cycles of adsorbent regeneration did not impact the adsorption equilibrium or kinetics. The high chemical and thermal stability of mesoporous carbons provide potential significant advantages over other commonly examined biofuel adsorbents, such as polymers and zeolites.     

Adsorption behaviors of organic vapors using mesoporous silica particles made by evaporation induced self-assembly method

Spherical mesoporous silica materials with controllable surface area and uniform pore size were synthesized via evaporation induced self-assembly (EISA) method in this study. Both well-ordered and less-ordered mesoporous silica particle (MSP) adsorbents were made via adjusting the surfactant/silica precursor molar ratio. And the relationships between the physical characteristics of MSP adsorbents and the acetone adsorption behaviors were examined for the first time. The results indicated that an increase in the specific surface area results in an increase in the acetone adsorption capacity. But if a further increase in the surface area causes a less structured adsorbent then the acetone adsorption capacity could become less even though the specific surface area is of the highest value of . The acetone adsorption capacity of well-ordered MSP adsorbent is more than twice of that of the commercial ZSM-5 zeolite adsorbent due to its relatively higher surface area and uniform pores. The well-ordered structure of MSP also leads to higher acetone adsorption efficiency and a sharper breakthrough curve due to fast pore diffusion.     

α-Amylase immobilization capacities of mesoporous silicas with different morphologies and surface properties

α-Amylase was encapsulated in several mesoporous materials (folded sheet mesoporous silica (FSM), cubic mesoporous silica (KIT-6), and two-dimensional hexagonal mesoporous silica (SBA-15)) that differed morphologically in terms of particle shape, pore size, and pore structure. The encapsulation capacity and thermal stability of encapsulated α-amylase were examined. The amount of α-amylase encapsulated increased with increasing pore size in the following order: SBA-15 < KIT-6 < FSM. Nitrogen adsorption experiments were performed before and after α-amylase encapsulation in mesoporous silicas with pore sizes larger than the size of α-amylase, confirming that α-amylase was encapsulated in the pores. Among mesoporous silicas with similar pore sizes, FSM was found to have the highest capacity for α-amylase encapsulation both per weight and per surface area of silica. Furthermore, α-amylase encapsulated in FSM demonstrated high thermal stability at 90 °C relative to the thermal stability of free α-amylase or free α-amylase encapsulated in other mesoporous silicas. Zeta potential measurements showed that the FSM surface had an isoelectric point that was lower than that of other mesoporous silicas, and hydrophilicity measurements showed that its surface was more hydrophilic. The surface properties of FSM contributed to the high thermal stability of the α-amylase encapsulated within the pores.     

Al-MCM-41介孔分子筛吸附喹啉的性能

在碱性条件下,采用水热晶化法,以偏硅酸钠为硅源,铝酸钠为铝源,CTAB为结构模板剂,成功合成出了含铝介孔分子筛Al-MCM-41。采用XRD、BET等手段对合成的Al-MCM-41进行表征,对柴油中的氮化物喹啉进行了吸附实验,考察了Al-MCM-41介孔分子筛对氮化物喹啉的吸附能力,探究了硅铝比为60的Al-MCM-41分子筛对喹啉溶液吸附的热力学和动力学行为,测得353.15～393.15 K 温度范围内的吸附等温线数据,用Langmuir、Freundlich方程对此进行拟合,并根据热力学原理计算得到吸附过程中的ΔH、ΔG、ΔS值和吸附表观活化能。结果表明, 硅铝比为60的Al-MCM-41具有较大的孔容、比表面积和较窄的孔径分布,结晶度和有序性高。等温吸附平衡符合Freundlich 等温线模型,其ΔH -0.7682 kJ·mol^-1,ΔG -28.1215 kJ·mol^-1, ΔS 73.2434 J·mol^-1·K^-1,吸附动力学符合Pseudo拟二级方程,E_a为2.8575 kJ·mol^-1。     

用于燃烧后CO2捕集系统的胺基固态吸附材料研究进展

随着工业化的发展和大量化石燃料的消耗,大量的CO₂气体排放到大气中并引发了一系列严重的环境问题,而采用燃烧后CO₂捕集技术可以有效地应对这一问题。寻找一种高效吸附、稳定、价格低廉的固态吸附材料对于开展燃烧后CO₂捕集系统的研究具有重要的实际意义。近年来,胺基固态吸附材料因其高CO₂吸附能力和高吸附选择性成为研究的热点。本文综述了近年来国内外学者对不同胺基固态吸附材料在合成方法、载体材料选择以及性能测试等方面进行的研究,重点讨论了以沸石分子筛、介孔硅分子筛、多孔碳和金属有机骨架为载体的胺基固态吸附材料对CO₂的吸附行为,并指出多孔载体材料的结构改进及有机胺和促进剂的合理选择将会成为未来胺基固态吸附材料的重点研究方向。     

Thermally robust chelating adsorbents for the capture of gaseous mercury: Fixed-bed behavior

Thermally robust chelating adsorbents for the capture of vapor-phase mercuric chloride (HgCl₂) have been developed, to address the issue of mercury removal from flue gases from coal-fired power plants. The adsorbents are mesoporous silica substrates functionalized with a chelating agent and coated with an ionizing surface nano-layer. This architecture enables selective, multi-dentate adsorption of mercury directly from the gas phase with high capacity. The capture efficiency of the adsorbents was evaluated in the fixed-bed mode for oxidized mercury at 160 °C. Two chelating adsorbents, one functionalized with 3-mercaptopropyltrimethoxysilane (MPTS) and the other with 2-mercaptobenzothialzole (MBT), were studied. For both adsorbents a high mercury uptake capacity was observed, several times higher than that of commercial activated carbon. The mechanism for mercury uptake in the two adsorbents is different. The effect of pore size on uptake was also evaluated. It was found that pore size does not have a significant effect on the mercury adsorption, and mercury diffusion through the ionic coating is believed to be the rate-limiting step for capture.