含氮有机物对活性碳纤维还原吸附银的影响广州市科技计划基金

用H3PO4、ZnCl2等活化剂分别制备了两种化学活化的活性碳纤维(HPSACF和ZCSACF),并通过水蒸汽活化制备了水蒸气活化活性碳纤维(SACF).研究了它们对水溶液中Ag(NH3)2+的还原吸附性能,并与活性碳(AC)的还原吸附性能进行了比较.不同方法制备的活性碳纤维(ACF)对Ag(NH3)2+的还原吸附能力有显著的差异,以磷酸活化法制备的ACF的还原能力最强,而AC也有一定的还原吸附能力.含氮有机物的吸附对活性碳纤维或活性碳的还原吸附能力有很大的影响,一般而言,吸附至碳吸附剂上的对硝基苯酚和苯胺可促进AC、SACF和HPSACF的还原能力,且苯胺的促进作用大于硝基苯酚的促进作用.     

ZnO/AC复合物的制备及其光催化性能研究

以Zn（NO3）2和Na2CO3为原料,采用直接沉淀与吸附法在粉末活性碳表面负载了ZnO纳米颗粒,制备了ZnO/AC复合光催化剂,并采用XRD,SEM等进行了表征。分别采用紫外光和可见光对10 mg.L^-1的甲基橙溶液进行光降解实验,结果表明：随着ZnO纳米颗粒负载量的增大,光催化活性先提高,然后有所下降。当ZnO与活性碳质量比为0.2时,复合光催化剂具有很高的光催化活性。     

掺杂稀土金属改性二氧化锰/活性碳超级电容器的研究

以KMnO4, Mn（CH3COO）2·4H2O和活性碳为原料, 利用化学共沉淀法, 合成氧化锰/活性碳（MnO2/AC）电极材料, 同时在制备过程中分别掺杂硫酸钴（CoSO4）和氧化铒（Er2O3）、硫酸钴和硫酸镧 （La2（SO4）3）、硫酸钴和硫酸镍（NiSO4）. 采用X射线衍射（XRD）和扫描电子显微镜（SEM）分析了MnO2/AC的结晶结构及表面形态. 采用循环伏安 （CV）和恒流充放电技术研究了MnO2/AC的电化学性能. 结果表明, 掺杂Co和稀土元素La及Er的MnO2/AC比未掺杂的具有更宽的窗口电位, 表现出更好的电容性能. 掺杂后的MnO2/AC内阻值有所增加, 电容量有所减少. MnO2/AC电容为275 F·g^-1, 掺Co和La的为200 F·g^-1, 掺Co和Er的为193 F·g^-1, 掺Co和Ni的为174 F·g^-1.     

高效复合催化剂Ag/Bi_2WO_6微米簇的制备及性质

在温和、无模板条件下利用水热法合成了簇状钨酸铋,通过超声还原法将银纳米粒子负载在其表面,得到复合催化剂Ag/Bi_2WO_6。采用XRD、SEM、XPS、UV-vis DRS等技术对样品进行了表征与测试。选择对硝基苯酚还原生成对氨基苯酚为模型反应,探讨了Ag/Bi_2WO_6的催化活性。结果表明,Ag的负载量为5.0%的复合样品催化活性最高,17 min内可以将4-NP全部催化还原。这可能是由于Ag纳米颗粒分散在Bi_2WO_6表面,比表面积大,表面能高,反应活性强。另外,模拟太阳光下,复合样品Ag/Bi_2WO_6作催化剂,以有机染料结晶紫为污染物模型,进行了光催化反应,研究了合成样品的光催化活性。结果显示,负载量为5.0%Ag/Bi_2WO_6的光催化降解结晶紫的活性最高。本研究对设计高效复合催化剂提供了新的思路和借鉴。     

水热法合成Ag2C03／ZnO异质结复合光催化剂及其光催化性能

采用水热法合成了一系列不同Ag2CO3含量的新型Ag2CO/ZnO异质结复合光催化剂,运用X射线粉末衍射（XRD）、扫描电镜（SEM）、X射线光电子能谱（XPS）、傅里叶变换红外光谱（FT-IR）、紫外-可见漫反射吸收光谱（UV-visDRS）等系列手段对所制备的光催化剂进行了表征,并以紫外光（254nm）为光源,评价了催化剂光催化降解甲基橙的活性,考察了不同Ag2CO3复合量、不同水热温度对ZnO复合光催化剂反应活性的影响．结果表明．当Ag2CO3含量为2％、水热温度为140℃,复合光催化剂具有最大的光催化活性,降解率达到86．31％．Ag2CO3/ZnO异质结复合光催化剂具有更高的光催化活性主要原因是复合光催化剂对紫外光有很强的吸收能力,适量A龅C03能提高光生电子一空穴对的分离效率,并改善催化剂的物理性能．     

镁合金表面钼酸盐磷酸盐复合转化膜的制备方法

本发明公开了一种（NH4^＋）xMoS2插层化合物，式中X值为0．2—3．0。其制备方法是首先利用正丁基锂对二硫化钼进行插层，得到锂插层二硫化钼，然后采用水剥层制备了二硫化钼悬浮液，并在氯化铵溶液中插层制备了（NH4^＋）xMoS2插层化合物，本产品可作为一种良好的固体润滑材料，也可与碱溶液共热得到单层二硫化钼。本发明解决了单层二硫化钼的储存问题，得到了稳定的（NH4^＋）xMoS2插层化合物，本发明的插层化合物是一种灰黑色粉末状固体，在机械、电子、航空航天、化工、材料等固体润滑领域有着重要的应用价值。     

铈对Ru/γ-Al2O3变换催化剂的改性研究

采用浸渍法制备了一系列钌基催化剂,以水煤气变换为探针反应,采用XRD、TPR和TPD等手段研究了铈对Ru/γ-Al2O3催化剂的改性机制.结果表明,铈的加入显著地提高了Ru/γ-Al2O3催化剂的变换反应活性,增加了Ru/γ-Al2O3催化剂的活性中心数,降低了催化剂的还原温度,增强了催化剂对H2O的吸附和活化作用.     

H_2O对不同状态Pd催化剂上低浓度CO催化氧化性能的影响

采用不同的Pd前驱体,通过浸渍法制备了系列Al_2O_3负载Pd催化剂,研究表明:Pd的化学状态、卤素离子的引入等不仅可直接影响催化剂的氧化活性,还可影响气氛中H_2O的作用。当Pd以氧化态存在时,以Pd(NO_3)_2的HBr溶液为前驱体所制备得到的BrC催化剂具有最高的反应活性,而以PdCl_2的HCl溶液为前驱体所得ClC催化剂的活性最低;经H2还原后,催化剂的活性均有显著的提高,其中以Pd(NO_3)_2为前驱体所得CH催化剂表现出最高的CO氧化活性,另外两种催化剂活性相差不大。同时对于还原态催化剂,气氛中的H_2O可抑制CH表面CO的吸附,并有利于O_2的吸附和活化,从而显著提高了CO的氧化活性;但Cl和Br引入后,H_2O的存在对CO吸附和活性影响不明显。当Pd以氧化态形式存在时,H_2O的引入可促进BrC和C催化剂上的CO氧化,其中BrC催化剂上的促进作用最为明显,但却抑制了以PdCl2的HCl溶液为前驱体所得ClC催化剂上的CO氧化。     

微波活化对过硫酸盐降解典型选矿药剂苯胺黑药的影响

采用微波活化过硫酸盐的高级氧化技术处理选矿废水中残留的典型选矿药剂苯胺黑药,研究了反应条件、微波功率、过硫酸盐浓度、反应溶液初始pH、金属离子Fe2+和Cu2+、水中常见阴离子（Cl-、HCO₃-、NO₃-和SiO₃2-）等变化因素对苯胺黑药降解效果的影响,并对反应产物和降解机理进行了分析。结果表明:微波活化过硫酸盐能够有效降解苯胺黑药;随着微波功率和过硫酸盐投加浓度的增加,苯胺黑药的降解率也随之升高;当溶液初始pH=3时苯胺黑药的降解效果最好;较低浓度金属离子Fe2+和Cu2+的添加可以有效辅助活化过硫酸盐,促进反应体系中苯胺黑药的降解;水中常见阴离子Cl-、HCO₃-、NO₃-和SiO₃2-对苯胺黑药的降解均为抑制效果;在反应体系中氧化降解苯胺黑药的过程中微波热效应为主要作用,而且在反应过程中SO₄-·起主导作用;反应180 min后,苯胺黑药的矿化效率为45.27%;通过液相色谱检测,推测苯胺黑药经微波活化过硫酸盐体系处理后先被氧化为邻二苯酚,再进一步被氧化降解为其他小分子物质、二氧化碳和水。      

封闭溶样-AAS法测定特高品位矿石中的金银

影响特高品位矿石中Au、Ag准确测定的因素主要有AgCl、PbCl2沉淀和Au、Ag矿物的硅酸盐包裹体,W、Mo、Sb和Pb等竞争吸附,容量分析的滴定终点干扰,以及待测溶液的介质及浓度等。研究确定了HCl-HNO3-KClO3（-NH4 HF2）和（ NH2）2 CS封闭溶样,泡沫塑料分段富集（或活性炭富集）,AAS法硫脲介质测定矿石中的Au、Ag。该方法可有效避免各影响因素干扰,且操作简便、不污染环境,分析结果的精密度（ RSD ）为0．66％～0．93％,国家标准样品加标回收率为98％～102％。     

ACF/CNT复合材料的制备及其对Cr(Ⅵ)的吸附性能

以硝酸镍为催化剂前驱体,C2H2为碳源,H2为还原气,N2为载气,采用化学气相沉积法(CVD)在活性炭纤维(ACFs)毡体的纤维表面催化生长碳纳米管(CNTs),制备ACF/CNT复合材料。经测定,所制复合材料比表面积可达62.56 m2/g;扫描电镜分析表明,CNTs在ACFs表面分布均匀而致密,经过表面修饰可以作为1种良好的吸附材料。选择低浓度的六价铬(Cr(Ⅵ))溶液进行吸附研究,考察振荡时间、溶液pH值以及溶液的初始浓度等因素对吸附行为的影响。实验结果表明,初始Cr(Ⅵ)浓度为1 mg/L,在25℃时,随着振荡时间的增长溶液中Cr(Ⅵ)的脱除率逐渐增加,在150 min时达到最大值49.48%。溶液中Cr(Ⅵ)的脱除率随着pH的减小而增大,当pH值为2.0时脱除率达91.50%,对Cr(Ⅵ)的吸附量随着溶液初始浓度的增加而增大,但是当初始浓度到达5.0 mg/L时,脱除效率到达最大值后开始降低。并对ACF/CNT复合材料的吸附机制进行了探讨。     

Sulfur Impregnation on Activated Carbon Fibers through H2S Oxidation for Vapor Phase Mercury Removal

Sulfur was impregnated onto activated carbon fibers (ACFs) through H2S oxidation catalyzed by the sorbent surface in a fixed-bed reactor. By changing the temperature and duration of the sulfur impregnation process, ACFs with different sulfur contents were developed. Characterization of ACFs before and after sulfur impregnation was conducted by surface area analysis, energy dispersive X-ray analysis, thermogravimetric analysis, X-ray photoelectron spectroscopy, and temperature programmed desorption. Vapor phase mercury adsorption experiments were carried out in a fixed-bed reactor. Sulfur was impregnated mainly as elemental sulfur and the amount of sulfur deposited on the ACF increased with an increase in impregnation temperature. Higher temperature leads to more uniform sulfur distribution inside the sorbent pores. The impregnation process can be explained by a combination of pore filling and monolayer adsorption, with the former mechanism predominating at low temperatures. In the absence of sulfur, the mercury adsorption capacity can be correlated with surface area and pore volume.     

氰化金和氰化银在活性炭上的吸附行为和特征

本文重点讨论Au(CN)_2~-和Ag(CN)_2~-在活性炭上吸附的行为和特征。 当矿浆中只有Au(CN)_2~-或Ag(CN)_2~-时,它们在活性炭上的吸附过程和特征相同;当矿浆中既有Au(CN)_2~-又有Ag(CN)_2~-时,它们的吸附过程和行为又不相同。 Ag(CN)_2~-对Au(CN)_2~-在活性炭上吸附的连续性没有影响,但对吸附容量有影响。无Ag(CN)_2~-时金在活性炭上的吸附容量为q=40.71C~(0.717),有Ag(CN)_2~-时(本文叙及条件),金在活性炭上的吸附容量为q=4.4368C~(0.4701)。 q——吸附平衡时金容量,mg/g.c; C——吸附平衡时液相金品位,mg/L。 受Au(CN)_2~-的影响,Ag(CN)_2`-在活性炭上的吸附行为变化很大,可由吸附变为解吸。因此,当Au(CN)_2~-和Ag(CN)_2~-存在于同一体系时,它们在活性炭上的吸附不能同时完成,金、银必须进行分段吸附才能获得满意的吸附效果。     

Control of PAHs from Incineration by Activated Carbon Fibers

The aim of this research was to use activated carbon fibers (ACFs) to adsorb 16 polycyclic aromatic hydrocarbon (PAH) species from flue gas emissions during incineration. The operation conditions included the presence of three activated carbon fibers, the adsorption temperature (200, 300, and 340°C), and the weight of the ACFs. The removal efficiencies of the gaseous and solid-state PAHs were evaluated respectively. It was found that the BET surface area did not affect PAH removal when the BET surface area was enough for PAH removal and micropore volume was the determinant parameter for PAHs removal. The best adsorption temperature in this study was 300°C. The removal efficiency of PAHs was proportional to the weight of ACFs.     

Effect of zinc and cerium addition on property of copper-based adsorbents for phosphine adsorption

A series of copper-based activated carbon (AC) adsorbents were prepared in order to investigate the effect of Zn, Ce addition on Cu-based AC adsorbent for phosphine (PH3) adsorption removal from yellow phosphorous tail gas. N2 adsorption isotherm and X-ray diffrac-tion (XRD) results suggested that the addition of Zn could increase the adsorbent ultramicropores, decrease the adsorbent supermicropores and the adsorbent average pore diameter. Therefore it enhanced the PH3 adsorption capacity. Appropriate amoun...     

低阶煤一步法制备活性炭的脱硫脱硝性能

 活性炭法是能实现多种污染物综合控制的烟气治理技术,可同时处理烧结过程中产生的二氧化硫和氮氧化物等有害物质,但由于活性炭较高的生产和使用成本,限制了其在烧结烟气多污染物净化领域的推广应用。以低阶煤为基炭,氧化球团为活化剂,利用低阶煤热解和气化反应与铁氧化物还原之间的耦合作用,一步完成低阶煤炭化和活化,制备活性炭(SF AC),并与商品活性炭(ZJ AC)在产品工业分析、比表面积、碘吸附值、脱硫脱硝性能和再生活性炭吸附性能等方面进行综合比较。结果表明,SF AC的碘吸附值、比表面积分别为695.13 mg/g、370.42 m2/g,而ZJ AC仅530.54 mg/g、157.50 m2/g,单独脱硫时SF AC、ZJ AC的穿透硫容分别为368.11 mg/g、73.58 mg/g,单独脱硝时SF AC、ZJ AC的穿透硝容分别为250.39 mg/g、14.99 mg/g,前者较后者具有更优的吸附性能;就再生性能而言,SF AC、ZJ AC的脱硫脱硝性能均出现下降,但前者的脱硫脱硝性能更优;与单独脱硫、脱硝相比,两种活性炭同时脱硫脱硝时脱硫性能均提高,脱硝性能却降低,采用NH₃低温催化还原可改善脱硝性能差的问题。     

Adsorption of Sulfur Dioxide on Activated Carbon from Oil-Palm Waste

Adsorption of sulfur dioxide (SO2) onto activated carbons prepared from oil-palm shells was investigated in this paper. Experimental results showed that the adsorption temperature and SO2 concentration significantly determined the amount of SO2 adsorbed and the equilibrium time. However, sample particle size had minimum effect on the equilibrium time. For a fixed SO2 concentration, the adsorption rate and adsorption kinetic parameters (activation energy and frequency factor) were obtained. A linearly proportional relationship between the Brunauer-Emmett-Teller surface area and the adsorptive capacity of the activated carbon from oil-palm shells was observed. An intraparticle Knudsen diffusion model based on a Freundlich isotherm was developed for predicting the amount of SO2 adsorbed and the SO2 concentration profile within the particle. Based on the estimated isotherm parameters and diffusion coefficients by experimental data fitting, this model could predict the amount adsorbed under different concentrations very well. However, this model was unsuitable for the activated carbon prepared from oil-palm shells by chemical activation because of the occurrence of chemisorption, which was related to the nature of the sample surface functional groups.     

Effect of rare earth addition on Cu-Fe/AC adsorbents for phosphine adsorption from yellow phosphorous tail gas

Phosphine(PH3) is a highly toxic air pollutant,commonly produced in phosphorous chemical industry.But it has received less research attention due to its handling difficultly.CO is the main content of the phosphorous chemical industry tail gas,the concentration of which is always more than 80 vol.%,and it can be the feed gas to produce various valuable products such as formate,oxalate,and methanol and so on.But,PH3 is one of the important barriers,which is harmful to the following chemical process.In order to make use of the tail gas,PH3 should be removed firstly,and CO should be covered in the whole purified procedure at the same time.In this work,the modified activated carbon(MAC) was used as the adsorbent to separate PH3 from the mixture tail gas.Series of MAC adsorbents were prepared for the adsorption of PH3,which loaded Cu-Fe and Ce(La),or separately.The PH3 adsorption capacities,chemical and physical properties of MAC were all investigated.The results showed that over 99% PH3 adsorption efficiency was achieved when used MAC adsorbents.The removal efficiency and PH3 adsorption capacity of the Cu-Fe-Ce/AC(20:1:0.4) were both much higher than those modified activated carbons.The maximum PH3 adsorption capacity was 71 mg of PH3/g of MAC on the Cu-Fe-Ce/AC,which were much higher than literature data using CuO only for adsorbing hydride gases.     

Effect of rare earth addition on Cu-Fe/AC adsorbents for phosphine adsorption from yellow phosphorous tail gas

Phosphine (PH₃) is a highly toxic air pollutant, commonly produced in phosphorous chemical industry. But it has received less research attention due to its handling difficultly. CO is the main content of the phosphorous chemical industry tail gas, the concentration of which is always more than 80 vol.%, and it can be the feed gas to produce various valuable products such as formate, oxalate, and methanol and so on. But, PH₃ is one of the important barriers, which is harmful to the following chemical process. In order to make use of the tail gas, PH₃ should be removed firstly, and CO should be covered in the whole purified procedure at the same time. In this work, the modified activated carbon (MAC) was used as the adsorbent to separate PH₃ from the mixture tail gas. Series of MAC adsorbents were prepared for the adsorption of PH₃, which loaded Cu-Fe and Ce (La), or separately. The PH₃ adsorption capacities, chemical and physical properties of MAC were all investigated. The results showed that over 99% PH₃ adsorption efficiency was achieved when used MAC adsorbents. The removal efficiency and PH₃ adsorption capacity of the Cu-Fe-Ce/AC (20:1:0.4) were both much higher than those modified activated carbons. The maximum PH₃ adsorption capacity was 71 mg of PH₃/g of MAC on the Cu-Fe-Ce/AC, which were much higher than literature data using CuO only for adsorbing hydride gases.