超疏水沸石咪唑酯骨架材料ZIF-90的制备及其气体吸附性能

以自制沸石咪唑酯骨架材料ZIF-90为原料,自制2,3,4,5,6-五氟苄胺为修饰剂,通过后修饰法制备了超疏水ZIF-90,采用SEM、XRD、FTIR等技术对其进行了表征,并进行了气体吸附性能测试。表征结果显示:制备的超疏水ZIF-90晶体结构和形貌良好;水接触角高达152.1°;修饰剂分子与ZIF-90晶体上的自由醛基成功发生缩胺反应。气体吸附实验结果表明:当相对压力小于0.02时,超疏水ZIF-90的CO_2吸附量较ZIF-90明显增大,CO_2/N_2和CO_2/CH_4的理想吸附选择系数由修饰前的15.76和4.88分别提升至33.28和17.13;超疏水ZIF-90具有优异的憎水性能。     

2种反应器中好氧颗粒污泥培养的比较研究

以絮状活性污泥为接种污泥,采用人工配制的模拟生活污水,分别在气提式序批反应器(SBAR)和序批式活性污泥反应器(SBR)中成功地培养出了成熟的好氧颗粒污泥.SBAR和SBR中的好氧颗粒污泥都具有稳定的基本形态结构,其微生物主要由杆菌和球菌组成,对COD的去除率可达到93%左右.对NH+4-N的去除率可达到98%以上.SBAR中好氧颗粒污泥的粒径主要分布、污泥体积指数(SVI)、比耗氧速率(SOUR)、TN去除率和TP去除率分别为0.45～2.00 mm、19.97 mL/g、47.68 g/(kg·h)、82%和65%;而SBR中好氧颗粒污泥的粒径主要分布、SVI、SOUR、TN去除率和TP去除率分别为0.18～1.00 mm、29.12 mL/g、43.21 g/(kg·h)、58%和50%.相对而言,SBAR更有利于好氧颗粒污泥的培养和运行.     

负载TiO2浮石对污水处理厂二沉池出水的矿化与灭菌研究

城市污水处理厂第二沉淀池出水的污染物浓度较低,经过矿化及灭菌等深度处理后可以回用,从而减轻对淡水资源的需求。本实验采用溶胶-凝胶法制备了负载TiO2的浮石光催化剂,对城市污水处理厂第二沉淀池出水进行了矿化及灭菌处理研究。采用低压汞灯对处理水样照射2h,有机物降解率可以达到50％,灭菌效率达到100％。处理后的水可以作为农作物灌溉、城市绿化和娱乐用水。负载在浮石表面的TiO2薄膜经过10次的光催化循环实验后,没有明显破损,可以再次循环使用。TiO2浮石具有质轻、机械性能好和价格低等优点,该方法处理废水的适用浓度低,可以广泛应用于微污染水和城市污水处理厂出水的深度处理。     

An important pathway for ozonolysis of alpha-pinene and beta-pinene in aqueous phase and its atmospheric implications

The aqueous ozonolysis of α-pinene and β-pinene was conducted under simulated tropospheric conditions at different pHs and temperatures. Three kinds of products, peroxides, carbonyl compounds, and organic acids, were well characterized, and the detection of these products provides effective evidence for understanding the atmospheric aqueous reaction pathway. We have two interesting findings: (1) the unexpected formation of methacrolein (MACR), with a yield of ～40%, in the α-pinene–O₃ aqueous reaction indicates a potentially new SOA formation pathway, because MACR is one of the important precursors of SOA; and (2) the surprisingly high yields of H₂O₂, ～60% for the α-pinene–O₃ reaction and ～100% for the β-pinene–O₃ reaction, indicates that H₂O₂ can be a significant contributor to the origin and transformation of oxidants in the atmosphere, especially in the humid regions. Moreover, we have determined the rate constant for aqueous reaction between MACR and H₂O₂ in pH 2 to 7 and obtained its upper limit as 0.13 M L^?1 s^?1. A mechanism concerning the formation of the species mentioned above is proposed, and it differs from that in the gas-phase reaction. We suggest that water plays a key role in the mechanism, by participating in the reactions as a direct reactant and by removing the excess energy of intermediates formed in the reactions.     

Concentrations of volatile organic compounds,carbon monoxide,carbon dioxide and particulate matter in buses on highways in Taiwan

Although airborne pollutants in urban buses have been studied in many cities globally, long-distance buses running mainly on highways have not been addressed in this regard. This study investigates the levels of volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO₂) and particulate matter (PM) in the long-distance buses in Taiwan. Analytical results indicate that pollutants levels in long-distance buses are generally lower than those in urban buses. This finding is attributable to the driving speed and patterns of long-distance buses, as well as the meteorological and geographical features of the highway surroundings. The levels of benzene, toluene, ethylbenzene and xylene (BTEX) found in bus cabins exceed the proposed indoor VOC guidelines for aromatic compounds, and are likely attributable to the interior trim in the cabins. The overall average CO level is 2.3 ppm, with higher average level on local streets (2.9 ppm) than on highways (2.2 ppm). The average CO₂ level is 1493 ppm, which is higher than the guideline for non-industrial occupied settings. The average PM level in this study is lower than those in urban buses and IAQ guidelines set by Taiwan EPA. However, the average PM₁₀ and PM_2.5 is higher than the level set by WHO. Besides the probable causes mentioned above, fewer passenger movements and less particle re-suspension from bus floor might also cause the lower PM levels. Measurements of particle size distribution reveal that more than 75% of particles are in submicron and smaller sizes. These particles may come from the infiltration from the outdoor air. This study concludes that air exchange rates in long-distance buses should be increased in order to reduce CO₂ levels. Future research on long-distance buses should focus on the emission of VOCs from brand new buses, and the sources of submicron particles in bus cabins.     

几种试剂对硝酸根光催化脱色甲基橙的影响

以NO^-₃为光催化剂,在紫外灯照射下,对甲基橙溶液进行光催化脱色。结果表明,叔丁醇、甲醇和乙醇对催化脱色反应有抑制作用; KBr和Na₂SO₄对脱色反应均有促进作用;而且KBr的加入量存在最佳值; Na₂SO₄的促进作用随Na₂SO₄的量的增加逐渐增强。Na₂CO₃的存在对甲基橙的脱色反应没有影响。K₂S₃O₈和NO^-₃之间存在较强的协同作用;KIO₃和NO^-₃之间存在相加作用;KBrO₃和NO^-₃之间存在拮抗作用。     

废弃印刷线路板碘化法浸金研究

针对碘化法从废弃印刷线路板中提取金的工艺设计,分别考察了碘的质量分数、n(I₂)/n(I^-)比值、固液比、双氧水的质量分数、pH值、浸出时间和浸出温度对金浸出率的影响。结合正交设计优化实验方法,提出了从废弃印刷线路板中碘化法浸取金的最佳工艺条件：碘的质量分数为1.1％,n(I₂)∶n(I^-)=1∶10,双氧水的质量分数为1.5％,浸出时间4 h,固液比为1∶10,浸出温度为常温（25℃）,溶液pH值为中性,此时金浸出率可达97.5％。     

CuCoOx/TiO2催化氧化NO性能研究

采用浸渍法制备了CuCoOx/TiO₂催化剂,考察了焙烧温度、反应温度、氧含量、NO浓度和空间速度对催化剂催化氧化NO性能的影响,并考察了催化剂的抗硫抗水性能。XRD、TPR和BET分析表明,350℃焙烧的催化剂具有CuCo₂O₄尖晶石结构,比表面积大,对NO的氧化效果好。在空速为5 000 h^-1,NO进口浓度500 mg/m³,含氧量10%的条件下,反应温度300℃时NO转化率可达79.5%,250℃时NO转化率接近50%。该催化剂具有良好的单独抗SO₂、抗H₂O毒化性能,H₂O和SO₂同时存在时很快失活。该催化剂可用于不同时含H₂O和SO₂的含NO气体催化氧化后再吸收处理。     

浸提分离法提取皂素清洁工艺研究

提出一种通过溶剂提取将游离皂苷与淀粉、纤维等成分分离,从源头上减少用水量、耗酸量和污染物排放量的皂素清洁生产工艺。首先对溶剂提取条件进行优化,得出最佳工艺条件为：90%（体积比）乙醇溶液,料液比1∶7,沸腾回流提取3 h,重复提取3次。然后通过气质联用（GC/MS）分析了皂素废水的有机物组成。研究结果表明,清洁工艺皂素产率为1.51%（降低3.82%）,用酸量比传统工艺减少了71%,头道液COD浓度降低了46%,每100 g原料排放的COD总量下降了84%;皂素废水的有机物污染物主要为糠醛及其衍生物,清洁工艺废水的有机物含量更低,更易降解。     

脂肪酰基氨基酸对矿物润滑油生物降解性的影响研究

通过生物降解试验研究了N-月桂酰基谷氨酸、N-月桂酰基甘氨酸、N-月桂酰基丙氨酸和N-油酰基甘氨酸4种脂肪酰基氨基酸对HVI 350矿物润滑油生物降解性的影响,采用高倍电子显微镜分析了生物降解过程中微生物数量和形态变化。结果表明,在矿物润滑油中添加少量脂肪酰基氨基酸后,矿物润滑油的生物降解性能明显改善,且生物降解过程中微生物数量增多、形态发生变化,这可能是脂肪酰基氨基酸增加了微生物的营养,且具有表面活性,有利于细胞的吸收,从而促进了矿物润滑油生物降解。