负Cu活性炭对氯气的吸附性能研究

活性炭作为一种多孔物质,具有很大的比表面积和较强的吸附性能,其广泛应用于吸附剂和催化剂的载体。本文采用浸渍法制得负Cu活性炭(用Cu/AC表示),并考察了其对氯气吸附性能的影响。利用XRD、FTIR对吸附前后的Cu/AC进行表征分析。研究表明,负载Cu后对氯气吸附性能有显著地提高,且经多次吸附后,结构骨架依然存在,稳定性较好。在0.22MPa、30℃时质量分数5%的Cu/AC最大吸附量为32.73%。     

玉米芯接枝共聚物对Cu(Ⅱ)的吸附性能研究

采用NaHSO3/H2O2氧化还原引发体系,以甲基丙烯酸、丙烯酰胺为混合单体,合成了玉米芯接枝共聚物。研究了玉米芯接枝共聚物对Cu(Ⅱ)的吸附性能,详细考察了溶液初始酸度、时间、金属离子初始浓度、温度以及吸附剂的碱化处理对吸附性能的影响,结果表明:在pH低于4时,酸度对吸附性能影响显著;吸附速率快,在20min左右就能达吸附平衡;Cu(Ⅱ)初始浓度的增加及温度的升高有利于吸附的进行;碱化处理可使吸附量提高数倍。此外,吸附热力学的研究表明,该吸附过程是吸热过程。     

表面负载不同金属离子的活性炭吸附二苯并噻吩

主要研究活性炭表面负载不同金属离子以提高其对二苯并噻吩吸附性能.通过浸渍法制备5种负载过渡金属离子活性炭Ag(Ⅰ)/AC、Cu(Ⅱ)/AC、Ni(Ⅱ)/AC、Zn(Ⅱ)/AC和Fe(Ⅲ)/AC.用静态吸附法测定了二苯并噻吩在不同活性炭上的吸附平衡等温线,并应用软硬酸碱理论分析和讨论活性炭表面负载不同金属离子对二苯并噻吩吸附性能的影响.结果表明活性炭表面负载Ag ,Ni2 、Cu2 或Zn2 离子,可提高其对二苯并噻吩的吸附,而活性炭表面负载Fe3 ,反而降低了其对二苯并噻吩的吸附能力.由于Ag 价格昂贵,而Ni2 、Cu2 和Zn2 价廉易得,而且Zn(Ⅱ)/AC、Cu(Ⅱ)/AC和Ni(Ⅱ)/AC对二苯并噻吩又具有良好的吸附能力,故表面负载Ni2 、Cu2 和Zn2 可改善活性炭吸附脱除油品中有机硫化物的能力.     

活性炭负载银吸附剂的制备与脱除苯并噻吩的研究

采用浓硝酸氧化改性的活性炭为载体负载金属Ag制备了Ag/AC系列吸附剂,并进行了模型柴油中苯并噻吩(BT)的吸附脱除性能研究。采用N2吸附、SEM、FT-IR及XRD技术对吸附剂进行了表征。结果表明,氧化改性增加了活性炭表面酸性基团,有利于脱除弱碱性的BT。以HNO3氧化改性后的活性炭为载体负载AgCl所制备的吸附剂具有最高脱硫率达91.8%。最后探讨了AgNO3在活性炭上的吸附行为及金属Ag对BT的吸附脱除机理。     

吸附制冷系统中固化吸附剂性能的实验研究

在吸附制冷系统中,常用的吸附剂为粉末或颗粒形态,吸附剂颗粒之间的热阻和吸附剂与传热面之间的接触热阻很大,而采用固化吸附剂可以有效提高吸附剂的导热性能。本文以硫化膨胀石墨(ENG-TSA)为基质制备了固化活性炭(AC)吸附剂和固化氯化钙(Ca Cl2)吸附剂,针对固化吸附剂设计了无翅片的吸附床结构,并建立了一个低压蒸气驱动的吸附式制冷系统。通过实验对固化吸附剂的性能进行了测试,分析了吸附剂的传热性能、循环时间和蒸发/冷凝温度对吸附制冷系统性能的影响。结果表明:采用AC/ENG-TSA吸附剂,系统COP、SCP和体积制冷密度分别达到0.140,86.1 W/kg和16.11 k W/m~3;采用CaCl_2/ENGTSA吸附剂,系统COP、SCP和体积制冷密度分别达到0.279,288.6 W/kg和54.03 k W/m~3,性能较传统的吸附剂有明显的提高。     

活性炭纤维(ACF)吸附二硫化碳(CS2)的研究

研究了商用活性炭纤维(Activated carbonf fiber-ACF)对二硫化碳(Carbon disulfide-CS2)的吸附件能,并与活性炭(Activated carbon-AC)、沸石吸附CS2的性能做了对比.重点考察了CS2浓度、吸附气流量、湿度和ACF含水量对CS2在ACF上吸附性能的影响.结果表明:相对于AC、沸石,ACF对CS2的吸附快、吸附率高,达46.5%;CS2浓度、吸附气流量增加,穿透点前移;湿度和含水量上升会明显降低ACF对CS2的吸附性能,当湿度升至65%时,吸附时间缩短28.6%;当含水量为质量分数45%时,穿透时间提前42.9%;当含水量增至质量分数60%时,CS2迅速穿透,ACF几乎不能再吸附CS2.     

低温吸附泵用椰壳活性炭材料的结构测试分析

活性炭的结构参数影响低温吸附泵的吸附抽气性能。为了优选适用于NBI装置低温吸附泵的吸附剂,研究分析了六种椰壳活性炭(AC1、AC2、AC3、AC4、AC5、AC6)的结构特征,经实验测试,得到低温吸附等温线。应用BET理论、t图法、DFT法对孔结构进行了分析研究,获得了各活性炭样品的比表面积、微孔比表面积份额、比孔容积、以及孔径分布等结构测试数据。结果表明,六种活性炭中,AC1和AC2结构参数性能更适合NBI装置低温吸附泵的吸附抽气性能需求。     

改性MCM-41的制备及其吸附Cr_2O_7~(2-)的热力学研究

以微硅粉为硅源,CTAB和PEG-6000为模板剂,采用水热法制备得到MCM-41介孔分子筛。以该MCM-41为载体,采用后接枝法将巯丙基三甲氧基硅烷引入到MCM-41的表面和孔道内,合成了巯基功能化的MCM-41介孔分子筛(SH-MCM-41),并采用XRD、N2吸附-脱附曲线和FT-IR对样品进行了表征。以巯基功能化的样品为吸附剂,对含Cr2O2-7的溶液进行了静态吸附实验,研究了pH值和初始浓度对吸附剂吸附性能的影响,探讨了吸附过程的热力学。结果表明,吸附剂吸附量随初始浓度和温度升高而增加,当pH值为1时吸附容量最大,达25.5mg/g。不同温度下Langmuir方程均呈现很好的拟合度,热力学平衡方程计算得ΔG0,ΔH=14.2kJ/mol,ΔS0,表明该吸附过程是自发的、吸热、熵增加的过程。     

三氯化铁改性活性炭(Fe3+-AC)对Cr(Ⅵ)的吸附研究

工业化发展导致废水中含有大量重金属离子，去除重金属离子成为水质净化的研究热点。以活性炭(AC)为主体吸附剂，进行三氯化铁改性，制备出三氯化铁改性活性炭吸附剂(Fe³⁺-AC),通过X射线衍射(XRD)、红外光谱(FT-IR)和扫描电镜(SEM)对其结构进行表征。结果表明：三氯化铁已成功改性活性炭，改性后吸附剂Fe³⁺-AC孔径较AC有所增大，更有利于离子吸附。进一步探究Fe³⁺-AC对Cr(Ⅵ)的吸附能力，吸附时间为300min,吸附剂投加量为0.2g, pH为6时，吸附效果最好，在此条件下，Fe³⁺-AC对Cr(Ⅵ)的去除率接近90%,为后续循环吸附研究奠定基础。     

吸附剂吸附热的计算分析

对分子筛和两种活性炭吸附剂进行了吸附等温线测试,并利用实验结果进行吸附热的计算,计算结果显示:CO的等量吸附热随着吸附量的增加逐渐减小,通过不同温度下的吸附等温线计算的等量吸附热相差不大;CO在分子筛上的等量吸附热大于在活性炭上的等量吸附热,且对于两种不同的活性炭对应的等量吸附热有较大的差异;不同的气体在同一种吸附剂上的吸附热大时,其对应的吸附量不一定大;实验结果显示了吸附过程的复杂性。     

Adsorption of poly(4-vinylpyridine) onto bentonites

The preparation of new adsorbents based on the coating of a poly(4-vinylpyridine) (P₄VP) polymer onto industrial bentonites was investigated. Two ways of synthesis were investigated, using dibromohexane (DBH) or its absence as a difunctional quaternizing agent in order to fasten the polymer by cross-linking. Several parameters (reagents ratio, type of bentonite, chemical stability in liquid media) were studied. Qualitative (IR and RMN spectroscopies) and quantitative (thermogravimetric) analyses of the samples were carried out.     

羽毛蛋白接枝丙烯酸-丙烯酰胺高吸水性树脂的吸附性能

通过水溶液聚合法合成了羽毛蛋白接枝丙烯酸-丙烯酰胺高吸水树脂,即FP-P(AA-AM)。研究了树脂在单一Cd2+溶液中的吸附行为以及在Cd2+、Cu2+、Zn2+三元混合溶液中的选择性吸附性能。结果表明,在单一Cd2+溶液中,FP-P(AA-AM)树脂对Cd2+的吸附容量随硫酸镉溶液浓度的增大而增大,最高可达2.4mmol/g。吸附Cd2+至饱和的树脂能在1mol/L的HCl溶液中很好的进行解吸附,3min时解吸附率即可达到83.3%。在较高浓度的三元金属离子混合溶液中,FP-P(AA-AM)树脂对3种离子呈现出一定的选择性吸附,其平衡吸附量顺序为:Cu2+Cd2+Zn2+。     

Adsorption of ammonium dinitramide (ADN) from aqueous solutions. 1. Adsorption on powdered activated charcoal

Investigations on the adsorption of ammonium dinitramide (NH(4)N(NO(2))(2)) (ADN) from aqueous solutions on powdered activated charcoal (PAC) were carried out in order to find out an effective and easier method of separating ADN from aqueous solutions. The effectiveness of PAC in the selective adsorption of ADN from aqueous solutions of ADN (ADN-F) and ADN in presence of sulfate (SO(4)(2-)) and nitrate (NO(3)(-)) ions (ADN-PS) was examined and compared using batch and column methods. The adsorption process follows both Langmuir and Freundlich adsorption isotherms and the isotherm parameters for the models were determined. The observed data favor the formation of monolayer adsorption. The adsorption capacities were found to be 63.3, 119, 105.3 and 82 mg of ADN per g of PAC for ADN-F (batch), ADN-PS (batch), ADN-F (column) and ADN-PS (column), respectively. Break-through curves for ADN-F and ADN-PS were obtained for the optimization of separation of ADN from aqueous solutions. Elution curves were generated for the desorption of ADN from PAC using hot water as eluent.     

Adsorption characteristics of As(V) on iron-coated zeolite

The sorption characteristics of arsenic(As(V)) on iron-coated zeolite (ICZ) were investigated through batch and column studies. As(V) was completely removed within 30 min in a concentration of 2mg/l, with a 100g/l dose of ICZ. Optimum dose of ICZ was 33.3g/l at a concentration of 20.12 mg/l and the effect of solution pH was negligible at a pH range of 3.0相似文献   

AlN在α-Al2O3(0001)表面吸附过程的理论研究

采用基于密度泛函理论的平面波超软赝势法,对α-Al2O3(0001)表面吸附AlN进行了动力学模拟计算,研究了AlN分子在a-Al2O3(0001)表面吸附成键过程、吸附能量与成键方位.计算表明吸附过程经历了物理吸附、化学吸附与稳定态形成的过程,其化学结合能达到4.844eV.吸附后AlN化学键(0.189±0.010nm)与最近邻的表面Al-O键有30°的偏转角度,Al在表面较稳定的化学吸附位置正好偏离表面O六角对称约30°,使得AlN与蓝宝石之间的晶格失配度降低.     

Adsorption properties of Cd(II)-imprinted chitosan resin

A Cd(II)-imprinted chitosan resin (Cd-ICR) was prepared for adsorption of Cd(II) from aqueous solutions. Batch adsorption experiments were performed to evaluate the adsorption conditions, selectivity and reusability as well as its application in the removal of Cd(II) from oyster hydrolysate. The results indicated that the maximum adsorption capacity of Cd-ICR was 0.795 mmol/g in sole Cd(II) solution at pH 5.0, 45 °C with equilibrium time 10 h. The selectivity coefficient of Cd(II) and other metal cations on Cd-ICR indicated an overall preference for Cd(II), which was much higher than that of non-imprinted chitosan resin. Cd-ICR could be reused for ten times with about 27% regeneration loss. FTIR spectra demonstrated that Cd(II) in Cd-ICR occurred on amino and secondary hydroxyl groups. The removal ratio of Cd(II) from oyster hydrolysate was 73.6%, while that of Ca(II) and Zn(II) were 6.2 and 9.9%, respectively. This suggests that Cd-ICR is a very promising adsorbent for selective removal of Cd(II) from aqueous solutions.