锰离子催化臭氧液相烟气脱硫实验研究

对Mn2+催化臭氧(O3)液相氧化脱除二氧化硫(SO2)进行了实验研究,以揭示Mn2+对臭氧液相氧化SO2的影响.采用标准碘量法测定了O3浓度曲线.实验比较了添加Mn2+前后吸收液对SO2的脱除效率,并研究了O3与SO2摩尔比([O3]/[SO2])、Mn2+浓度对SO2脱除效率的影响.在[O3]/[SO2]=0.5、未添加Mn2+时O3对SO2的氧化效率为35%,而添加Mn2+后的氧化效率达到70%.随着[O3]/[SO2]的增大,SO2脱除效率逐渐增加,而且脱除效率也随Mn2+浓度的增加而增加,合适的Mn2+浓度范围为1.2×10-2~1.2×10-1mol/L.     

烟雾箱模拟乙炔和NOx的大气光化学反应

利用自制光化学烟雾箱进行了一系列表征实验并模拟了乙炔和氮氧化物NO_x在室温（20±1）℃下的大气光化学反应．讨论了乙炔与NO_x的协同作用对光化学反应产生O₃的影响．实验得到了O₃和NO₂的壁损失分别为5.80×10^-6 s^-1和2.41×10^-6 s^-1,相对于模拟实验中的O₃和NO₂,该损失可以忽略．测得了单支40 W黑光灯的有效光强为0.64×10^-3 s^-1（以NO₂的光解速率表示）．经过净化空气的本底校正后,讨论了不同乙炔浓度、NO_x浓度以及光照强度对体系产生O₃的影响,计算了乙炔的增强反应活性值（incremental reactivity, IR）,4组实验的IR最大值分别为1.76×10^-2、2.68×10^-2、2.04×10^-2和2.84×10^-2．并发现IR值与乙炔的初始浓度以及光照强度关系密切,与NO_x初始浓度关系不大．     

Applying model simulation and photochemical indicators to evaluate ozone sensitivity in southern Taiwan

Ozone sensitivity was investigated using CAMx simulations and photochemical indicator ratios at three sites (Pingtung City, Chao- Chou Town, and Kenting Town) in Pingtung County in southern Taiwan during 2003 and 2004. The CAMx simulations compared fairly well with the hourly concentrations of ozone. Simulation results also showed that Pingtung City was mainly a volatile organic compounds (VOC)-sensitive regime, while Chao-Chou Town was either a VOC-sensitive or a NOx-sensitive regime, depending on the seasons. Measurements of three photochemical indicators (H2O2, HNO3, and NOy) were conducted, and simulated three transition ranges of H2O2/HNO3 (0.5–0.8), O3/HNO3 (10.3–16.2) and O3/NOy (5.7–10.8) were adopted to assess the ozone sensitive regime at the three sites. The results indicated that the three transition ranges yield consistent results with CAMx simulations at most times at Pingtung City. However, both VOC-sensitive and NOx-sensitive regimes were important at the rural site Chao-Chou Town. Kenting Town, a touring site at the southern end of Taiwan, was predominated by a NOx-sensitive regime in four seasons.     

氟啶虫胺腈在不同有机溶剂中的光化学降解

利用液质联用和气相色谱（HPLC-Mass和GC）,研究了氟啶虫胺腈在两种不同光源下于4种不同溶剂（正己烷、甲醇、乙腈、丙酮）中的光化学降解.结果表明,以氙灯为光源,1.0、5.0、20.0mg·L-1的氟啶虫胺腈在4种溶剂中的降解半衰期分别为11.62、8.33、10.80h（正己烷）,5.30、5.81、7.05h（甲醇）,1.72、1.99、2.79h（乙腈）,83.49、37.46、64.77h（丙酮）.以紫外灯为光源,1.0、5.0、20.0mg·L-1的氟啶虫胺腈在4种溶剂中的降解半衰期分别为5.29、4.25、5.49min（正己烷）,2.19、2.97、5.88min（甲醇）,0.86、1.99、1.13min（乙腈）,330、365、198min（丙酮）.氟啶虫胺腈的降解反应主要为还原、水解反应,影响其降解速率的主要因素是光源和溶剂的种类,氟啶虫胺腈的浓度对其降解速度也有一定影响.     

Fabrication of supported acid catalytic composite fibers by a simple and low-cost method and their application on the synthesis of liquid biofuel 5-ethoxymethylfurfural

In this paper, sulfonic groups functionalized annealed bio-based carbon microspheres loaded polytetrafluoroethylene (A-BCMSs-SO3H@PTFE) fibers with high activity, high stability, and easy regeneration were successfully fabricated by a simple method using low-cost raw materials. The characterization results showed that the annealed biomass carbon microspheres derived from waste Camellia oleifera shells were evenly distributed on the polytetrafluoroethylene fibers and the sulfonic groups can be successfully loaded on the surface of annealed biomass carbon microspheres by room temperature sulfonation. Subsequently, the as-prepared A-BCMSs-SO3H@PTFE fibers were applied to the acid-catalyzed synthesis of liquid biofuel 5-ethoxymethylfurfural. The catalytic experiment results indicated that the annealing temperature and time during catalyst preparation have a significant effect on the activity and selectivity of A-BCMSs-SO3H@PTFE fibers. The results of catalytic reaction kinetics showed that the yield of 5-ethoxymethylfurfural can reach more than 60％after 72 h of acid-catalyzed reaction. The stability test showed that the as-prepared A-BCMSs-SO3H@PTFE fibers still maintained a stable acid catalytic activity after four recycles.     

稀土催化剂在环保领域中的研究和应用

综述了稀土材料在催化剂中的作用机理,介绍了稀土催化剂在汽车尾气治理、烟气脱硫脱硝治理、室内空气净化、焦化污水处理以及其他领域的研究与应用进展,展望了稀土催化剂在环保产业中的发展前景。     

石油炼化无组织VOCs的排放特征及臭氧生成潜力分析

选取我国光化学活跃的珠江三角洲地区(PRD)典型石油炼化工艺的炼油装置、化工装置和污水处理装置,采用离线和在线的多种先进仪器监测其VOCs的无组织排放特征,并采用间、对-二甲苯/苯(X/B)、甲苯/苯(T/B)、乙苯/苯(E/B)比值分析其VOCs的老化特征,采用最大增量反应活性法(MIR)、等效丙烯浓度法和OH自由基反应速率法(L_OH)3种方法综合评价其VOCs的化学反应活性及臭氧生成潜势(OFP).研究发现,炼油装置区和化工装置区总挥发性有机物(TVOC)浓度早晚高,中午低;污水处理区呈双峰趋势.3个装置区无组织排放的VOCs中烷烃浓度均占比最高,同一装置区内的不同装置VOCs排放特征不同.石化企业X/B、T/B和E/B值较城区和郊区的高,化工装置区的压缩碱洗装置区(CAW)T/B值最大.石化企业VOCs的活性较城区和郊区的强,其平均OH消耗速率常数为15.22×10^-12cm³/(mol·s),最大增量反应活性为4.21mol(O₃)/mol(VOC).化工装置区对石化企业OFP总量的贡献最高,为84.83%;其次是污水处理区,12.95%;炼油装置区最低,为2.22%.化工装置区的CAW对石化企业OFP贡献率最高,为34.26%;污水处理区的浮选池(FT)贡献率最低,为0.36%.     

Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

Highly dispersed gold nanoparticles were supported on coal-based activated carbon (AC) by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient temperature. Nitrogen adsorption-desorption, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the catalysts before and after ozone decomposition. The results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating, exhibiting higher catalytic activity for ozone decomposition. The pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition, and the best pH value was 8. In the case of space velocity of 120000h⁻¹, inlet ozone concentration of 50mg/m³, and relative humidity of 45%, the Au/AC catalyst maintained the ozone removal ratio at 90.7% after 2500min. After being used for ozone decomposition, the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly, while its specific surface area and pore volume only decreased a little. Ozone was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.     

Home composting as an alternative treatment option for organic household waste in Denmark: An environmental assessment using life cycle assessment-modelling

An environmental assessment of the management of organic household waste (OHW) was performed from a life cycle perspective by means of the waste-life cycle assessment (LCA) model EASEWASTE. The focus was on home composting of OHW in Denmark and six different home composting units (with different input and different mixing frequencies) were modelled. In addition, incineration and landfilling was modelled as alternatives to home composting. The most important processes contributing to the environmental impact of home composting were identified as greenhouse gas (GHG) emissions (load) and the avoided emissions in relation to the substitution of fertiliser and peat when compost was used in hobby gardening (saving). The replacement of fertiliser and peat was also identified as one of the most sensible parameters, which could potentially have a significant environmental benefit. Many of the impact categories (especially human toxicity via water (HTw) and soil (HTs)) were affected by the heavy metal contents of the incoming OHW. The concentrations of heavy metals in the compost were below the threshold values for compost used on land and were thus not considered to constitute a problem. The GHG emissions were, on the other hand, dependent on the management of the composting units. The frequently mixed composting units had the highest GHG emissions. The environmental profiles of the home composting scenarios were in the order of −2 to 16 milli person equivalents (mPE) Mg⁻¹ wet waste (ww) for the non-toxic categories and −0.9 to 28 mPE Mg⁻¹ ww for the toxic categories. Home composting performed better than or as good as incineration and landfilling in several of the potential impact categories. One exception was the global warming (GW) category, in which incineration performed better due to the substitution of heat and electricity based on fossil fuels.     

柴油机排气微粒过滤催化处理技术及进展

介绍了柴油机微粒后处理催化捕集器特点 ,评述了过滤器催化再生方法 ,综述了蜂窝陶瓷载体涂层及催化剂活性组分研究现状。重点阐述了微粒再生催化剂研究进展及其发展趋势