活性碳纤维对水中五氯酚的吸附性能研究

文章研究了活性碳纤维(ACFs)对水中五氯酚(PCP)的吸附行为、吸附条件及再生性能。结果表明,PCP在ACFs上的吸附容量较大,Langmuir及Freundlich等温线都能较好地反映其吸附行为;ACFs对水中分子和离子状态的PCP均可吸附,在最佳的静态吸附和动态吸附条件下,PCP去除率分别可以达到97%和99.8%;用0.01mol/L NaOH溶液进行再生,吸附量基本不变,五氯酚回收率可达90%以上。     

蚯蚓和堆肥固定化添加模式对漆酶降解土壤五氯酚的影响

利用土壤五氯酚（PCP）污染模拟实验,研究两种不同生态型蚯蚓（赤子爱胜蚓Eisenia foetida和壮尾环毛蚓Amynthas robustus E.Perrie）和堆肥固定化添加模式对漆酶降解土壤PCP的影响。在42 d培养期内,测试了不同处理下PCP质量分数、漆酶活性,以及土壤呼吸和微生物碳氮等微生物指标。结果表明：堆肥固定化漆酶降解土壤PCP的效果优于壳聚糖固定化漆酶和自由漆酶,主要原因是堆肥固定化漆酶能够有效地提高漆酶稳定性,减缓其活性下降速度。此外,堆肥还能提高土壤微生物的数量与活性,显著提升土壤漆酶的活性。添加两种生态型蚯蚓对漆酶活性影响不显著,但均可以显著提高土壤微生物的数量与活性,加速土壤中PCP的降解。壮尾环毛蚓对土壤微生物数量与活性的提升效果优于赤子爱胜蚓。     

五氯酚胁迫对转基因杨树光合光响应特性的影响

以从美国引入的转基因杨树(Populus deltoides×nigra,DN34)为材料,设置0、50、100 mg·kg~(-1)三个五氯酚胁迫质量分数开展温室盆栽试验,利用Li-6400便携式光合作用测量系统研究五氯酚污染胁迫下转基因杨树对光强的生理响应.结果表明:与对照相比,相同光强下50和100 mg·kg~(-1)质量分数的五氯酚胁迫均降低了转基因杨树叶片的净光合速率(P_n)、蒸腾速率(T_r)、胞间CO_2摩尔分数(C_i)和气孔导度(G_s).因此高质量分数五氯酚比低质量分数五氯酚对转基因杨树光合作用产生更大的抑制响应.     

Changes in phototactic behavior of Daphnia magna clone C1 242 in response to copper, cadmium and pentachlorophenol

In order to develop a sound biotechnique for monitoring water quality that builds on the previous experiments carried out in our laboratory, a specific D. magna clone C1242 was used to study the effects of pollutants on phototactic behavior, in all experiments, the animals showed a stable and repeatable phototactic index approximated 0.2 in the presence and 0.4 in the absence of fish kairomenes, which decreased significantly in response to pollutants. There existed no pollutant x fish kairomone interaction, indicating the changes in phototactic behavior of animals imposed by pollutants were independent of the presence of fish kairomones. The detection limits for changes in phototactic behavior of D. magna clone C1 242 are 0.04 mg/L for copper, 0.02 mg/L for cadmium, and 0.80 mg/L for PCP, respectively, quite lowerthan LC50(48 h). The changes in phototactic behavior in presence to pollutants occurred quickly(3 h) compared to the period over whole acute toxicity tests. Therefore, D. magna clone C1 242 could be potentially used to monitor water quality. Moreover, the phototactic behavior did not decrease further in the pollutant mixtures employed in our experiments compared to individual pollutants, except in the Cd-PCP Lre.atme~t.This fact suggests that the formation of water quality criteria must be based upon pollutant mixture tests.Keywords: Daphnia; phototactic behavior; copper; cadmium; pentachlorophenol; fish kairomenes     

二氧化锰氧化降解五氯酚

以二氧化锰为氧化剂,研究了pH 4.12的水溶液中五氯酚氧化降解的反应动力学,并讨论了反应溶液的pH对反应动力学的影响.结果表明,五氯酚对二氧化锰的氧化作用具有较强的反应感受性.在pH一定和二氧化锰充分过量的条件下,随着反应的进行,五氯酚的降解速度变慢,遵循的不是简单的准一级反应动力学而是复合的反应动力学.此外,随溶液pH由3.5升高6.6,五氯酚的降解速度发生显著地下降.运用溶剂萃取和气质联用仪的分析方法,检测到2个主产物和1个次产物.其中,次产物是由四氯-1,4-氢醌与四氯儿茶酚组成的混合物;2个主产物是由五氯酚氧自由基偶合而成的二聚体,且是同分异构体.在观测到的表面反应动力学和降解产物的基础上,提出了五氯酚被二氧化锰氧化降解的反应流程图.     

利用厌氧颗粒污泥处理氯代有毒有机物

用能进行还原脱氯的微生物富集物接种，在小型试验装置内成功地培养出了具有还原脱氯功能的颗粒污泥。五氯苯酚能被这种颗粒污染完全脱氯并进一步分解为甲烷和二氧化碳。四氯乙烯和其他氯代乙烯能被颗粒污还原脱氯为乙烯。这种脱氯的颗粒污泥可用来处理含有五氯苯酚和氯乙烯类的废水和地下水。     

Formation and emission of chloroanisoles as indoor pollutants

GOAL, SCOPE AND BACKGROUND: Complaints by residents of frame-houses about musty odour in the houses has become an increasing problem within the last years. An additional problem is that the odour is transferred to clothes and skin. The persons themselves do not recognize the smell after a while because of adaptation. Serious social problems are the result. For a long time, the smell was explained to be from mould due to construction-based humidity problems. However, in an increasing number of houses, no indications were found for elevated levels of mould growth. METHODS: Air and material samples were taken from 5 houses, which show typical musty odours, and analysed with respect to chlorophenols and chloroanisoles. Additionally, some samples were analysed for lindane and its metabolites, because lindane was commonly used together with pentachlorophenol (PCP) for wood protection. RESULTS AND DISCUSSION: Meticulous analysis resulted in the identification of chloroanisoles, mainly 2,3,4,6-tetrachloroanisole. These substances are known from corky wines and from contamination of food from pentachlorophenol (PCP) treated pallets and result from microbiological metabolic processes. Pentachlorophenol was commonly used to protect wood from fungi in Germany mainly in the later 60s and 70s. Details of these processes, as well as effective methods to identify chloroanisoles in the problem houses, are described. CONCLUSIONS: Chloroanisoles formed by metabolism of PCP have been well known to contaminate food or wine. Here, they were identified and are probably responsible for the musty odours in the frame houses. Since it is quite clear that these substances were not components of building materials used in the houses, an explanation for chloroanisole formation is proposed. Localized dampness probably favours microbial growth associated with metabolic conversion of chlorophenols to the corresponding chloroanisoles, primarily 2,3,4,6-tetrachloroanisol, which spread throughout the buildings, resulting in the observed odours. RECOMMENDATIONS AND OUTLOOK: The group of chloroanisoles has been recognized as important indoor pollutants as they possess musty odours at extremely low concentrations, e.g. for 2,4,6-trichloroanisole in a range of 5-10 ppt in air (Staples 2000). On the basis of currently available toxicological data, exposure of the occupants to the concentrations of chloroanisoles measured is not associated with a health risk. No correlation could be observed between concentrations of chloroanisoles and PCP in house dust and indoor air. However, chloroanisoles are good indicators for possible PCP-treatment of wood in frame houses and their detection should initiate investigations on PCP contamination. Research is continuing to identify the microorganisms involved and to devise a remediation procedure for affected houses.     

五氯酚及其钠盐中氯代二恶英类分析

采用ＨＰＬＣ和ＧＣ／ＭＳ的方法，对国产ＰＣＰ及其钠盐中的ＰＣＤＤｓ，ＰＣＤＦｓ进行了分析。测定了所有２，３，７，８－取代同系物。此外，还根据各ＣＤＤｓ，ＣＤＦｓ的毒性当量因于ＴＥＦｓ，计算了其毒性当量Ｉ－ＴＥＱｓ，分别为１４２，９２ｎｇ．ｇ＾－１。在前述基础上，仨算了由于ＰＣＰ及其钠盐的应用，引起的ＰＣＤＤｓ，ＰＣＤＦｓ环境输入。约为２４０ｋｇ／ａ。     

接种白腐菌堆肥修复五氯酚污染的土壤

采用4组堆肥装置A、B、C、D,分别往五氯酚污染土壤中不加外来菌、加入固定化黄孢原毛平革菌(Phanerochaete chrysosporium)、加入游离黄孢原毛平革菌及暴露在空气中不做任何处理.对其进行对比研究,探讨了利用堆肥的方法对五氯酚污染土壤进行生物修复的可行性.结果说明,添加黄孢原毛平革菌进行堆肥修复其效果要好于不加菌的效果,经过60d的堆肥,PCP基本得到降解,降解率都达到了94%以上,其中固定化菌又优于游离菌,固定化菌在第9d对PCP的降解率就达到了50%.此外,通过分析种子发芽率,有机质,微生物量碳等多项指标可以看出各组堆肥的腐熟情况都比较理想,为黄孢原毛平革菌降解五氯酚的过程提供了良好的外部环境,使土壤修复与堆肥能较好地结合起来.     

Optimization of enrichment processes of pentachlorophenol (PCP) from water samples

The method of enriching PCP( pentachlorophenol ) from aquatic environment by solid phase extraction (SPE) was studied.Several factors affecting the recoveries of PCP, including sample pH, eluting solvent, eluting volume and flow rate of water sample, were optimized by orthogonal array design(OAD). The optimized results were sample pH 4; eluting solvent, 100% methanol; eluting solvent volume, 2 ml and flow rate of water sample, 4 ml/min. A comparison is made between SPE and liquid-liquid extraction(LLE) method. The recoveries of PCP were in the range of 87.6%-133.6% and 79%-120.3% for SPE and LLE, respectively. Important advantages of the SPE compared with the LLE include the short extraction time and reduced consumption of organic solvents. SPE can replace LLE for isolating and concentrating PCP from water samples.