废LCD面板有机材料水热资源化产乙酸

LCD面板主要由附着偏光片及液晶等有机材料的玻璃面板构成。有机材料的去除及资源化利用是废LCD面板处理的第一步。在水热条件下对废LCD面板进行了降解产酸研究。研究考察了反应温度、反应时间、氧化剂用量、水用量及pH值等对水热产乙酸产率及选择性的影响。通过正交实验确定了水热产乙酸的最佳操作条件：反应温度325℃,反应时间5min,氧化剂（30％H2O2）0．6mL,用水量2mL,近中性环境（pH6-6．5去离子水）。此条件下,乙酸产率及选择性分别为68．83％及70．56％。结果表明,以废LCD面板有机材料为原料,采用水热技术进行产乙酸反应,可实现其资源化再利用。     

木屑处置漏油事故的室内模拟

用锯木屑作为吸附材料,0#柴油为吸附对象进行室内模拟实验,研究了木屑对纯油、水中浮油的吸附以及吸油后的木屑在水中的漂浮性能;并以木屑粒径、木屑投加量、振荡频率、油膜厚度为研究指标,设计了5因素4水平的正交实验,考察了各因素对0#柴油的吸附量、去除率以及木屑漂浮率的影响并对优化条件进行了讨论。结果表明,在实验研究范围内,木屑对水中柴油的吸附速度极快,1min即可达到饱和,饱和吸附量为8．08g／g;木屑在水中漂浮性能良好,静态时经72h漂浮,漂浮率维持在92％左右;振荡频率为150r／min时,72h内漂浮率维持在68％以上;最佳吸油条件组合为吸附剂粒径10～20目,振荡频率120r／min,木屑投加量0．7g,油膜厚度1．65mm。     

昆明市污水排水系统产甲烷规律的模拟实验研究

通过对昆明市餐饮和居民生活污水厌氧模拟实验研究,初步探讨生活污水中CH4的产生规律,实验结果表明,在自然条件下,餐饮和居民生活污水中产生的甲烷浓度最大值分别为1.63 mg/L和3.82 mg/L。并且将COD、硫酸盐、硫化物、TN的浓度变化与甲烷浓度变化进行Pearson简单相关性分析,结果表明,1/COD、COD/硫酸盐和1/TN与甲烷在置信度为0.01时极显著相关,硫化物与甲烷在置信度为0.05时不相关;COD、硫酸盐和TN浓度的变化对生活污水中甲烷的产生起关键性作用。对居民生活污水中甲烷产生规律进行温度和pH控制分析研究,实验结果表明,生活污水在25~30℃时,24 h内甲烷产生量最大值为8.6494 mg/L,明显大于其他温度段的甲烷产生量;在pH为7~8之间时,甲烷的产生量在24 h内达到的最大值为3.0477 mg/L,明显高于其他pH控制段的甲烷产生量。     

电解-水生植物-软隔离带复合技术治理重污染河流的中试研究

为了探索重污染河流的治理技术,2011年3月在无锡市新区鸿山镇徐塘桥河开展生态治理示范工程,通过电解技术、种植高等水生植物和构建软隔离带复合工程技术改善河流水质。实验结果表明,通过电解技术,可以迅速降低TP、氨氮（NH4＋-N）和COD;但较难减少TN。通过软隔离带可以有效隔离外源污染,在较短时间内改善河流TN、TP、COD的平均水平,但是难以提高河流的生态系统稳定性。电解能够有效的降解大分子有机物,为水生植物提供良好的生长环境,之后再种植水生植物,能够进一步降低的TN、TP。通过电解一水生植物一软隔离带复合技术不仅能够全面改善河流水质的平均水平,而且能够修复水生生态系统,提高生态系统稳定性。     

城市生活垃圾焚烧处理过程中重金属迁移规律研究

通过采集厦门2个垃圾焚烧发电厂进厂垃圾、渗滤液、飞灰、炉渣和烟气样品,分析垃圾组成成分及各组分的重金属含量,结果表明,垃圾中以厨余、橡塑类和纸类为主,共占到垃圾干基的78．08％,重金属含量大小次序为Zn〉Cu〉Pb〉Cr〉Ni〉Cd〉Hg;垃圾渗滤液中除Zn外,其他金属的含量都较低,一厂渗滤液中重金属Ni、Zn迁移量较大,分别达到24．46％和8．52％。二厂渗滤液中重金属的迁移有相同的趋势,但含量相对较高。垃圾焚烧后其重金属主要分布在飞灰和废渣中,烟气中的含量非常少,不同金属的含量均有差别,这与金属的性质有很大关系;通过浸出毒性分析,飞灰中重金属酸溶态含量多,容易浸出,属于危险废物。同时,不同烟气处理工艺产生的飞灰的重金属浸出量有很大差别。     

Different reaction mechanisms of diphenylether and 4-bromodiphenylether with nitrous acid in the 355 nm laser flash photolysis of mixed aqueous solution

The microscopic reaction mechanisms of diphenylether (DPE) and 4-bromodiphenylether (4-BrDPE) with nitrous acid (HNO(2)) in the absence of O(2) have been explored by the 355nm laser flash photolysis. It was proposed that OH radical, from the photolysis of HNO(2), added to DPE forms the C(12)H(10)O-OH adduct while added to 4-BrDPE forms the 4-BrDPE-OH and 4-BrOH-DPE adducts. The first-order decay rate constants of the C(12)H(10)O-OH adduct, 4-BrDPE-OH adduct and 4-BrOH-DPE adduct were measured to be (1.86+/-0.14)x10(5)s(-1), (2.19+/-0.04)x10(5)s(-1) and (1.56+/-0.03)x10(5)s(-1), respectively. The final photolysis products of DPE and HNO(2) identified by GC/MS analysis were phenol, o-hydroxydiphenylether, p-hydroxydiphenylether and p-nitrodiphenylether, while the final photolysis product of 4-BrDPE and HNO(2) identified by LC/MS analysis was mainly the dimer.     

Simultaneous compartmentalization of lead and arsenic in co-hyperaccumulator Viola principis H. de Boiss.: an application of SRXRF microprobe

The cellular distributions of Pb and As in the leaves of co-hyperaccumulator Viola principis H. de Boiss. were inspected by synchrotron X-ray fluorescence spectroscopy (SRXRF). The results revealed that Pb and As had similar compartmentalization patterns in the leaves. Both elements were enriched in the bundle sheath and the palisade mesophyll. In comparison with the sheath and the mesophyll, the vascular bundle and the epidermis contained lower levels of Pb and As. The palisade enrichment of Pb and As indicated that V. principis H. de Boiss. may have a special mechanism on detoxification of toxic metals within the mesophyll cells. Relative concentrations of both Pb and As in trichome bases were higher than those in trichome rays. The results of hierarchical cluster analysis and correlation analysis confirmed that the distribution of Pb was similar to that of As in the leaves, and their distribution patterns were different from the nutrient elements, such as K, Ca, Mn, Fe, Ni, Cu and Zn. In vivo cellular localization of Pb and As in the leaves provides insight into the physiological mechanisms of metal tolerance and hyperaccumulation in the hyperaccumulators.     

Occurrence of phthalates in sediment and biota: relationship to aquatic factors and the biota-sediment accumulation factor

Phthalate compounds in sediments and fishes were investigated in 17 Taiwan's rivers to determine the relationships between phthalate levels in sediment and aquatic factors, and biota-sediment accumulation factor (BSAF) for phthalates. Mean concentrations (range) of di(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBzP) and di-n-butyl phthalate (DBP) in sediment at low-flow season were 4.1 (<0.05-46.5), 0.22 (<0.05-3.1) and 0.14 (<0.05-1.3)mgkg(-1)dw; those at high-flow season were 1.2 (<0.05-13.1), 0.13 (<0.05-0.27) and 0.09 (<0.05-0.22)mgkg(-1)dw, respectively. Trace levels of dimethyl phthalate (DMP), diethyl phthalate (DEP) and di-n-octyl phthalate (DOP) in sediment were found in both seasons. Concentrations of DEHP in sediments were significantly affected by temperature, suspended solids, ammonia-nitrogen, and chemical oxygen demand. The highest concentration of DEHP in fish samples were found in Liza subviridis (253.9mgkg(-1)dw) and Oreochromis miloticus niloticus (129.5mgkg(-1)dw). BSAF of DEHP in L. subviridis (13.8-40.9) and O. miloticus niloticus (2.4-28.5) were higher than those in other fish species, indicating that the living habits of fish and physical-chemical properties of phthalates, like logKow, may influence the bioavailability of phthalates in fish. Our data suggested that DEHP level in river sediments were influenced by water quality parameters due to their effects on the biodegradation processes, and that the DEHP level in fish was affected by fish habitat and physiochemical properties of polluted contaminants.     

Effects of rare earth elements on the distribution of mineral elements and heavy metals in horseradish

In order to investigate the effects of rare earth elements (REEs) on horseradish, the distribution of the mineral elements and heavy metals in different organs of horseradish have been studied by using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Meanwhile, three variable major parameters, namely the concentration of REEs, the type of REEs, and the growth stage of plant were chosen. The results indicated that the test REEs, Ce(III) and Tb(III), could be accumulated in leaves, stems and roots of horseradish. In addition, we found that the content of mineral elements was increased in horseradish treated with 20mgl(-1) of Ce(III), but not those with the 20mgl(-1) of Tb(III). Moreover, the content of mineral elements in horseradish was decreased with the increasing concentration of REEs (100, 300mgl(-1)). Furthermore, we found that there were the opposite effects on the content of the heavy metals in horseradish treated with REEs. Finally, we found that the effect of REEs on the accumulation of REEs, and the content of mineral elements or heavy metals of horseradish during vigorous growth stage, no matter positive or negative, was more obvious than that of the other growth stages. These results demonstrated that the distribution behaviors of mineral elements and heavy metals in horseradish can be affected by the type and concentration of REEs, and the growth period of plant.     

A rapid spectrophotometric determination of persulfate anion in ISCO

Due to a gradual increase in the use of persulfate as an in situ chemical oxidation (ISCO) oxidant, a simple measurement of persulfate concentration is desirable to analyze persulfate distribution at designated time intervals on/off a site. Such a distribution helps evaluate efficacy of ISCO treatment at a site. This work proposes a spectrophotometric determination of persulfate based on modification of the iodometric titration method. The analysis of absorption spectra of a yellow color solution resulting from the reaction of persulfate and iodide in the presence of sodium bicarbonate reveals an absorbance at 352 nm, without significant interferences from the reagent matrix. The calibration graph was linear in the range of persulfate solution concentration of 0-70 mM at 352 nm. The proposed method is validated by the iodometric titration method. The solution pH was at near neutral and the presence of iron activator does not interfere with the absorption measurement. Also, analysis of persulfate in a groundwater sample using the proposed method indicates a good agreement with measurements by the titration method. This proposed spectrophotometric quantification of persulfate provides a simple and rapid method for evaluation of ISCO effectiveness at a remediation site.