磷酸活化活性炭对Cu2+的吸附特征研究

寻求廉价而高效的吸附材料为目的,研究向日葵秸杆基活性炭对铜离子的吸附性能。以向日葵秸秆为原料,经H3PO4活化制备活性炭,通过静态实验研究了其对水溶液中Cu2+的吸附特性,考察了溶液pH值、吸附温度和离子强度对吸附的影响,探讨了吸附热力学、动力学和吸附机理。结果表明:溶液pH值为5～6时活性炭对Cu2+的去除效果最好;向50 mL 170 mg·L-1的溶液中加入0.5 g活性炭,温度为45℃、吸附时间为1 h时,对Cu2+的去除率可达98.3%;Langmuir方程能更好地描述Cu2+在活性炭上的等温吸附特征,静态吸附容量可达41.03 mg·g-1;吸附过程符合拟二级动力学过程,且为吸热的化学吸附过程,膜扩散为速率控制步骤,离子交换可能在吸附过程中起了重要作用。     

Efficient degradation of drug ibuprofen through catalytic activation of peroxymonosulfate by Fe3C embedded on carbon

Ibuprofen(IBU),a nonsteroidal anti-inflammatory drug,is becoming an important member of pharmaceuticals and personal care products(PPCPs)as emerging pollutants.To degrade IBU,magnetic Fe_3C nanoparticles embedded on N-doped carbon(Fe_3C/NC)were prepared as a catalyst by a sol–gel combustion method.As characterized,the Fe_3C/NC nanoparticles were composed of a NC nano-sheet and capsulated Fe_3C particles on the sheet.The Fe_3C/NC nanoparticles were confirmed an efficient catalyst for peroxymonosulfate(PMS)activation to generate sulfate radicals(SO_4~(·-)),single oxygen(~1O_2)and hydroxyl radicals(·OH)toward the degradation of IBU.The added IBU(10 mg/L)was almost completely removed in 30 min by using 0.1 g/L Fe_3C/NC and 2 g/L PMS.The catalyst was confirmed to have good ability and excellent reusability through leaching measurements and cycle experiments.A catalytic mechanism was proposed for the catalytic activation of PMS on Fe_3C/NC,which involves both Fe_3C reactive sites and N-doped carbon matrix as reactive sites in Fe_3C/NC.Moreover,the degradation pathway of IBU in the Fe_3C/NC-PMS system was proposed according to the detections of degradation intermediates.     

热活化过硫酸盐降解水体和土壤中氰化物的效能和机制

近年来,氰化物引发的环境问题日益受到关注,但相关研究较少.本文利用热活化过硫酸盐技术对水体和土壤中的氰化物的降解过程和机制进行了研究,以期为氰化物的去除提供依据.首先采用批式实验,探究了温度、过硫酸盐添加量和初始pH对水溶液中氰化物降解效果的影响,然后在水溶液氰化物降解实验基础上,采用模配土壤进行了土壤氰化物降解实验.水溶液氰化物降解实验的研究结果表明,过硫酸盐 添加量和温度对于氰化物的降解具有显著影响.当温度从25 ℃升高到70 ℃时,铁氰和亚铁氰的降解率分别从11.06%和17.66%升高到98.12%和97.94%.过硫酸盐添加量从0.5 g?L^-1提高至3 g?L^-1时,铁氰和亚铁氰的降解率分别从38.27%和35.82%升高到99.05%和99.66%.当 体系的初始pH值为4.5~9.0时,初始pH对于氰化物的降解影响并不明显,但当pH为强碱性时（如pH=12）,氰化物的降解效果受到显著抑制.土壤氰化物降解实验的结果表明,当活化温度为60 ℃时,铁氰和亚铁氰的降解效率均随过硫酸盐增加而升高,最高降解率分别达46.88%和56.04%.与水溶液中氰化物的降解情况进行对比,发现土壤中氰化物的降解效率远低于水溶液体系.通过探究4种共存阴离子（包括Cl^-、CO₃^2-、H₂PO₄^-、腐殖酸）对氰化物降解过程的影响,发现腐殖酸对氰化物的降解呈现显著的抑制作用,且浓度越高抑制作用越明显,这可能是影响 土壤系统中氰化物降解效率重要原因.本研究通过自由基淬灭实验及氰化物降解产物分析试验证实热激发过硫酸盐产生的SO₄^.-和HO^.对氰化物降解起重要作用,将各种金属-氰络合物最终降解为NO₃^-和CO₂等终产物.     

零价铁活化过硫酸盐降解污水中萘普生的研究

为了提高零价铁(ZVI)活化过硫酸盐(PS)的ZVI/PS体系对有机污染物萘普生(NAP)处理的技术水平,即实现对污水中NAP的有效降解.采用对比试验,通过设置不同投加量的PS与ZVI的方式,观察在不同酸碱度条件下NAP的降解量.研究结果表明,酸性条件下,当PS投加量为0.5mM或ZVI投加量为1.50mM时,NAP的...     

活化温度对竹柳基活性炭性能及其制备过程中副产物组成的影响

以一种常见的环境修复材料竹柳为原料来制备竹柳基活性炭(WAC),考察了不同活化温度(400、450、500、550、600℃和650℃)对WAC性质及其除污染性能的影响,同时评估了制备过程中气态和液态副产物的生成规律与利用潜能.结果表明,随着活化温度的升高,WAC产率下降,热解油产率上升,而热解气产率相对稳定.六组WAC均具有较高的比表面积(BET),最高可达1526 m2·g-1,但BET值随活化温度的升高呈下降趋势;WAC的碘吸附值和亚甲基蓝吸附值最高可达1122.25 mg·g-1和415.50 mg·g-1,对重金属Pb2+和硝基苯的最大吸附量分别为9.20mg·g-1和4.21 mmol·g-1.WAC制备过程中热解气主要组分为H2、CH4、CO和CO2,随活化温度升高,H2和CH4含量上升,CO2含量下降,热解气的总燃烧热值升高.热解油的组分较为复杂,杂环类、烷烃类、烯烃类和有机酸类有机物含量较高,且随活化温度变化明显,在活化温度为650℃时,热解油的燃烧热最大.     

Determining distribution of heavy metal pollution in terms of ecological risk levels in soil of industrially intensive areas around Istanbul

The aims of the present study were to measure the concentrations of As, Cr, Co, Fe, and Zn in soils from two heavily industrialized areas and to assess the degree of heavy metal pollution by using the indices enrichment factor and the geo-accumulation index, as well as assessing the potential ecological risk. The concentrations of the selected elements in the environmental samples were determined by the neutron activation analysis. The pollutant concentrations in the studied areas showed that the soils were characterized by a high pollution from As and Cr due to the industrial facilities in the area. The concentrations in the Tuzla industrial area were 79–1215 mg/kg of Cr, 17–84 mg/kg of As, 22,000–54,000 mg/kg of Fe, 101–258 mg/kg of Zn, and 8–23 mg/kg of Co. The results for the Cerkezkoy industrial area were found to be 46–196 mg/kg of Cr, 6–24 mg/kg of As, 17,000–25,000 mg/kg of Fe, 67–136 mg/kg of Zn, and 7–10 mg/kg of Co. The contamination in the soils from heavy metals was assessed based on enrichment factor, geo-accumulation factors, and ecological risk indices. The results were compared with the data from other industrial areas in Turkey. It was found that the metals As and Cr showed higher concentrations in Tuzla than in other examined industrial areas. The results for Cerkezkoy industrial area indicate that the area is not as contaminated as the other industrial areas in Turkey.     

The two faces of high self‐monitors: Chameleonic moderating effects of self‐monitoring on the relationships between personality traits and counterproductive work behaviors

This study examines whether and how self‐monitoring moderates the relationships between two personality traits (agreeableness and conscientiousness) and counterproductive work behavior directed toward the organization (CWB‐O) and toward other employees (CWB‐I). High self‐monitors strive to attain personal goals related to status and prestige enhancement by adjusting their behavior to what the situation requires or allows for. We propose that the status enhancement motive can take on two different yet related forms—impression management (interpersonal potency) and opportunism (win‐at‐all‐costs)—depending on relevant situational cues. We hypothesize that in public, interpersonal settings where their behavior is visible to others, high self‐monitors' desire to enhance their status by looking good to others suppresses the natural expression of low agreeableness via increased engagement in CWB‐I. Conversely, we hypothesize that in private, non‐interpersonal settings where their behavior is rarely visible to others, high self‐monitors' desire to enhance their status by doing whatever it takes to get what they want intensifies the natural expression of low conscientiousness via increased engagement in CWB‐O. On the basis of two independent samples of participants, results of moderated multiple regression analyses provided support for the hypotheses. Copyright © 2013 John Wiley & Sons, Ltd.     

CDs-BOC复合催化剂可见光下活化过硫酸盐降解典型PPCPs

本研究通过简便的水热和煅烧两步法合成了一种新型光催化剂,该方法用碳量子点（CDs）修饰BiOCl纳米片.制备的纳米复合材料（CDs-BOC）通过X射线衍射（XRD）、扫描电子显微镜（SEM）、高分辨率透射电子显微镜（HRTEM）、紫外-可见漫反射吸收光谱（DRS）、X射线光电子能谱（XPS）和稳态荧光光谱（PL）等手段进行了表征.结果表明,此材料成功地引入了CDs.7% CDs-BOC纳米复合材料的光吸收边界被增强至可见光区域（424 nm）,并提高了光致电子-空穴对的分离效率.为了提高有机污染物降解的效果,过硫酸盐（PS）被引入了CDs-BOC光催化体系中.由于复合纳米催化剂具有出色的光催化能力,光生电子可以有效活化PS,产生更多的活性氧化物质.在可见光（λ>420 nm）照射下,20 min内可以完全去除5 mg·L^-1对-乙酰氨基酚（AAP）.通过自由基淬灭实验和电子顺磁共振波谱（EPR）,探明了此体系具有多种活性氧化物质：·OH、·SO₄^-、·O₂^-和h⁺,并提出了降解反应机制.以上结果体现出CDs-BOC/PS体系在光催化处理水污染方面具有广阔的应用前景.     

粉煤灰活化技术在诺砂制品中的应用研究

对激发粉煤灰活性的方法(物理活化和化学活化)进行了探讨,提出了一种能够大幅度提高粉煤灰活性的有效方法——细磨和化学激发复合方法。用此法活化粉煤灰制得的诺砂制品,其早期强度显著提高。同时对其活化机理进行了分析。     

活化温度对蜂窝状活性炭结构和脱硫性能的影响

以糠醛渣碳粉为原料，配以一定比例的粘结剂和增强材料，制备出了可用于烟气脱硫的蜂窝状活性炭，考察了活化温度对蜂窝状活性炭结构和脱硫性能的影响。结果表明：随着活化温度的升高，样品的比表面积增大，类石墨微晶尺寸减小，类石墨有序结构逐渐变得无序成为乱层石墨结构，样品的脱硫能力增大。