柴油吸附脱氮吸附剂的研究进展

吸附脱氮是目前应用比较广泛的方法之一。根据吸附剂的不同,其吸附效果也有很大的差别。吸附剂按表面极性可以分为极性吸附剂和非极性吸附剂。其中,活性氧化铝,硅胶,白土,分子筛,磷钼酸属于极性吸附剂,而活性炭属于非极性吸附剂。有些吸附剂的吸附脱氮效果还不是很理想,因此吸附剂的选择和其改性已经成为现在研究的重点。介绍了近几年来这两类柴油脱氮吸附剂的研究情况及其进展,并对未来吸附剂的研究提出了展望。     

Bio‐Regeneration of Desulfurization Adsorbents by Selected P. delafieldii R‐8 Strains

Abstract

Adsorption properties of different adsorbents such as reduced NiY, AgY, alumina, 13X, and activated carbon were studied with dibenzothiophene (DBT) and naphthalene as model compounds. The desorption of DBT was carried on thermo gravimetric–differential thermal analysis (TG‐DTA). The interaction of DBT with different adsorbents follows the sequence: activated carbon > reduced NiY > AgY > activated alumina > 13X. The bio‐regeneration of these adsorbents was studied with P. delafieldii R‐8 as desulfurization strains. Adding P. delafieldii R‐8 cells can improve DBT desorption from adsorbent AgY. The desorption of DBT from adsorbents by bio‐regeneration of adsorbents follows the sequence: 13X > alumina > AgY > reduced NiY>activated carbon. The presence of naphthalene can decrease the desorption of sulfur compounds. The adsorption capacity of AgY decreases for the first time recycling and then changes little. The decrease of the adsorption capacity is due to the loss of Ag⁺ ions.     

汽油吸附脱硫技术研究进展

综述了物理吸附脱硫、反应吸附脱硫以及选择性吸附脱硫技术的优缺点,并介绍了常用的吸附剂。认为选择性吸附脱硫技术是最有可能实现低硫汽油的脱硫技术,但是目前存在吸附剂吸附容量低,选择性不高的缺陷,因此未来研究的重点应该集中在吸附剂的开发上。     

载体对负载型CuCl吸附脱硫剂性能的影响

采用等体积浸渍-焙烧自还原法制备系列以氯化亚铜为活性组分的负载型吸附脱硫剂,载体分别为氧化铝、不同孔径硅胶、13X分子筛和活性炭。对不同种类硫化物进行吸附实验,利用微库仑滴定仪对吸附后的溶液测试。结果表明,载体类型对吸附剂脱硫效果影响明显,而且不同硫化物的吸附硫容有较大差别,氧化铝吸附剂有较好的脱硫效果。     

High-performance adsorptive desulfurization by ternary hybrid boron carbon nitride aerogel

Separation of aromatic organosulfur compounds is vital for upgrading the feed to clean fuel products, however, it remains a formidable challenge for the present adsorbents. Herein, a series of novel aerogel-like boron carbon nitride (BCN) with three-dimensional interconnected porous networks were fabricated via a hydrogel template and freeze-casting strategy. The as-prepared aerogel-like BCN had a variable carbon content and a flexible size of graphene domain on its porous structure. The optimal BCN aerogel represents the top-level of adsorptive desulfurization (ADS) capacity for aromatic organosulfur compounds (30.8 mg S/g adsorbent), strikingly higher than the state-of-the-art aerogels adsorbents (17.1 mg S/g adsorbent) reported under similar conditions. A selective adsorption for dibenzothiophene in the presence of aromatic hydrocarbons, nitrogen compounds were also achieved on BCN aerogel. The adsorption isotherm and XPS measurement reveal heterogeneous adsorption on the BCN aerogel via π–π and Lewis acid–base interactions.     

Cu-ACFS深度脱硫吸附剂的制备与性能

采用浸渍法制备了活性碳纤维（ACFS）负载CuCl的深度脱硫吸附剂Cu-ACFS。在常温常压下,研究了吸附剂对汽油模型溶液中噻吩硫的静态吸附脱硫性能,并优化了吸附剂的制备条件。结果表明,吸附剂的CuCl负载量随浸渍时间的延长刚开始增加很快,到24h以后趋于平衡,吸附剂的脱硫率随着吸附剂中CuCl负载量的增加而增加,最高可达到89．29％,Cu（I）在ACFS上的最优负载量为49．5962mg／g,对应吸附剂的硫吸附量为11．7074mg/g,处理后模型溶液的硫含量由179×10^-6降低到30×10^-6以下,且吸附剂的再生性能良好。     

Cu-ACFS深度脱硫吸附剂的制备与性能

采用浸渍法制备了活性碳纤维(ACFS)负载CuC l的深度脱硫吸附剂Cu-ACFS。在常温常压下,研究了吸附剂对汽油模型溶液中噻吩硫的静态吸附脱硫性能,并优化了吸附剂的制备条件。结果表明,吸附剂的CuC l负载量随浸渍时间的延长刚开始增加很快,到24 h以后趋于平衡,吸附剂的脱硫率随着吸附剂中CuC l负载量的增加而增加,最高可达到89.29%,CuⅠ()在ACFS上的最优负载量为49.596 2 mg/g,对应吸附剂的硫吸附量为11.707 4 mg/g,处理后模型溶液的硫含量由179×10-6降低到30×10-6以下,且吸附剂的再生性能良好。     

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。     

选择吸附脱硫研究进展

燃油中的含硫化合物在高温燃烧时生成的硫氧化物是大气中主要的污染物之一,对环境和人类健康有极大的危害。本文介绍了目前所发展的燃油脱硫的常用方法,重点阐述了吸附脱硫技术的研究进展。首先对吸附脱硫剂的开发现状进行了介绍,对目前发展的多种吸附脱硫剂包括活性炭、金属有机物框架、表面分子印迹聚合物、无机吸附剂的吸附脱硫量、选择吸附性、吸附影响因素进行了深入分析,总结了不同吸附剂的脱硫机理,并对不同吸附剂的再生方法、再生后的吸附效果进行了概述和评价。随后对比总结了这几类吸附剂的优缺点。最后介绍了目前吸附脱硫技术所存在的问题,指出开发在非硫化合物存在的情况下对含硫有机物具有高选择性、再生性能好的吸附脱硫剂是未来的发展趋势。     

活性炭用于柴油深度脱硫研究进展

综述了活性炭作为吸附剂和催化剂在柴油深度脱硫方面应用的新进展。通过表面热氧化和负载金属离子对活性炭表面进行化学性能改性,有效提高对柴油中噻吩类硫化物的吸附性能。活性炭作为催化剂,能有效催化过氧化氢和氧化柴油中的噻吩类硫化物而达到催化氧化脱硫。活性炭在柴油深度脱硫方面具有广阔的应用前景,但要真正实现其在脱硫上的工业化应用,尚需加强其表面化学性能改性、再生、吸附和催化氧化机理等方面的研究。     

燃油吸附脱硫研究进展

在清洁燃油生产技术中,吸附脱硫由于运行成本低和操作条件温和,被认为是目前最具前景的非加氢脱硫技术之一。吸附脱硫技术在温和的条件下将燃油中的有机硫选择性吸附脱除,而其核心是高效的固体多孔吸附剂材料。本文综述了目前吸附脱硫的吸附机理和吸附剂研究进展,主要从物理吸附、化学吸附和反应-吸附耦合三种吸附机制出发,重点介绍了不同吸附机制的脱硫吸附剂的研究进展及应用,从脱硫选择性、吸附热力学和动力学、选择性等方面深入分析和比较了不同吸附脱硫体系。最后对基于物理吸附、化学吸附和反应-吸附耦合机制的三种脱硫技术进行了总结,指出了目前在真实油品中吸附脱硫仍面临的竞争吸附等问题以及未来亟待进一步关注的方向。     

多孔材料对柴油脱色及脱碱性氮性能的对比研究

以焦化柴油和催化柴油加氢精制混合柴油作为原料,在一定条件下,考察了不同类型固体吸附剂对柴油脱色脱碱性氮的效果。静态实验结果表明,活性炭吸附剂的脱色效果最好,ASTM D1500色度达到0.2;硅酸铝吸附剂的脱碱性氮效果最好,脱除率达到90%。动态实验结果表明,活性炭吸附剂的胶质饱和吸附量最高,达到5.58%,但碱性氮饱和吸附量仅有0.45%。硅酸铝吸附剂的脱碱性氮效果最好,碱性氮吸附容量为0.91%,碱性氮饱和吸附量达到1.24%。与新鲜剂相比,采用高温焙烧再生,活性炭吸附剂能够完全恢复脱色脱胶质能力;采用极性溶剂再生,硅酸铝吸附剂能够完全恢复脱碱性氮能力。     

FCC汽油吸附脱硫剂研究新进展

对FCC汽油进行吸附脱硫,吸附剂的选择是关键。论述了分子筛类吸附剂、金属氧化物类吸附剂、活性炭、黏土类吸附剂和其他一些吸附剂在吸附机理、改性、脱硫效果、再生等方面的研究进展,特别是各类吸附剂改性后对硫化物的脱除效果。指出吸附剂吸附选择性及吸附容量的提高和吸附机理的深入研究是今后研究的重要方向。     

燃料油中硫化物的选择性吸附研究进展

综述了不同吸附剂脱硫和选择性吸附两方面的机理及研究进展。在燃料油选择性吸附脱硫研究的吸附剂中,使用最多的是金属阳离子改性的Y型分子筛,以Cu、Ni和Ce改性的Y型分子筛最为成熟。其吸附脱硫机理主要包括π-络合吸附和金属S—M键作用。燃料油（以汽油和柴油为主）组成复杂,含大量烯烃、芳烃、烷烃及少量的氮化物、氧化物、水及胶质,影响吸附剂的吸附脱硫效果,而烯烃和芳烃严重影响吸附剂的选择性吸附脱硫性能。各种吸附剂对富含烯烃或芳烃的燃料油中的硫化物选择性和硫容量不同,但都不高。研究吸附剂与燃料中的硫化物的选择性吸附机理,对研发具有高选择性和高吸附容量的吸附剂起推动作用。     

Adsorption of amino acid derivatives on calixarene carboxylic acid impregnated resins

Macrocyclic host molecules calixarene carboxylic acid derivatives are found to act as powerful extractants for biologically important amino compounds. A series of adsorbents were prepared from a methacrylate-based polymer Amberlite XAD-7 by impregnation with various calixarene derivatives, for adsorptive recovery of amino acid derivatives. The larger macrocycles calix[6]arene and calix[8]arene carboxylic acid derivatives were more effective for adsorption of amino acid derivatives on the impregnated resin than the calix[4]arene derivative. Since adsorption proceeds mainly via electrostatic interaction, the carboxylic acid groups introduced into the calixarene platform were important for adsorption of cationic amino acid derivatives. The adsorption selectivity for amino compounds using adsorbent impregnated with the calix[6]arene carboxylic acid derivative depends simply on the hydrophobicity of the adsorbates.     

多孔炭吸附脱除噻吩类硫研究进展

综述了目前多孔炭吸附剂在脱除噻吩类硫化物中的应用,分别介绍了多孔炭及改性多孔炭在吸附脱硫中的应用。重点介绍了改性多孔炭包括氧化改性及金属改性法的活性炭和介孔炭吸附脱硫研究,指出采用氧化一金属复合改性活性炭的方法可显著提高吸附脱硫能力。介孔炭由于具有较高的比表面积、较窄的孔径分布、极好的化学和热稳定性,用在吸附脱硫将可能成为未来的研究热点。     

Separation of Toxic Organotin Compounds from Aqueous Solution by Adsorption

Abstract

The adsorption characteristics of organotin compound (tributyltin oxide) are established on activated carbons, polymeric adsorbent, and synthetic carbonaceous adsorbents. Maximum adsorptive capacity is obtained with activated carbon containing high percentage of macropores (100–500 Å). For this carbon the adsorptive capacity (g organotin adsorbed/g of adsorbent) at breakpoint is 0.30 and the capacity at exhaustion (with 30 mg/L organotin solution) is 0.50.     

High performance sorbents for diesel oil desulfurization

Sorbents with different Ni loading supported on silica–alumina (SiAl) and activated carbon (AC) were synthesized and tested for removal of sulfur compounds from a model diesel oil, containing nearly 250 ppmw S as benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). A state-of-art Commercial Ni-based sorbent and two Norit activated carbons were also tested for comparison. Moreover, the influence on sorbents uptake capacity of the presence of aromatics in amounts representative of real diesel oils was studied. Both commercial and home-made materials performed worse in presence of aromatic compounds. Probably, the latter competed with the refractory sulfur compounds (DBT and 4,6-DMDBT) in the adsorption on active sites. As a first important result of the investigation the sorbents carrying 45% and 30% of Ni on SiAl showed a breakthrough uptake capacity of nearly, respectively, 2 and 2.6 times higher than Commercial sorbent as a consequence of their higher Ni dispersion and surface area. Moreover, activated carbons and the sample with 28%Ni on AC showed an even higher breakthrough uptake capacities. In particular, the deposition of nickel on activated carbon is an innovative approach which takes advantage of the selectivity of Ni towards S-species and the high adsorptive capacity of AC support.     

Metal-loaded polystyrene-based activated carbons as dibenzothiophene removal media via reactive adsorption

To improve the desulfurization capability of activated carbons, new metal-loaded carbon-based sorbents containing sodium, cobalt, copper, and silver highly dispersed within the carbon matrix were prepared and tested at room temperature for dibenzothiophene (DBT) adsorption. The content of metals can be controlled by selective washing. The new adsorbents showed good adsorption capacities and selectivity towards DBT. The metals incorporated to the surface act not only as active sites for selective adsorption of sulfur-containing aromatic compounds, but also as structural stabilizers of the carbon materials, and as catalyst initiators in reactive adsorption. Depending on the reactivity of the metal used, the adsorption capacity of the activated carbons significantly varied. Cobalt and copper loaded carbons showed the highest uptakes, due to not-well defined catalytic synergetic effects. Besides, the presence of sulfur compounds in the structure of the carbon as a result of the sulfonic moiety of the precursor, results in sulfur-sulfur specific interactions leading to an enhancement in the adsorption capacity for DBT removal.     

Adsorption and desorption kinetics for hydrophilic and hydrophobic vapors on activated carbon

Adsorption dynamics are of fundamental importance in applications of adsorbents in real situations. The adsorption/desorption characteristics of a series of adsorbates, with varying hydrophilic/hydrophobic and structural characteristics, for activated carbon BAX950, were investigated for temperatures in the range 288-323 K. These data provide a comprehensive kinetic study of adsorption/desorption for an activated carbon. The results are discussed in relation to the adsorbent pore structure and functional group concentration, adsorptive structure and adsorption mechanism. The study provides evidence for a compensation effect where activation energy and ln(pre-exponential factor) parameters obtained from the Arrhenius equation exhibit a linear correlation.