磷在水和沉积物中的形态

文章介绍了生物可利用态的磷(总磷、有机磷、无机磷)在土耳其奥龙特斯河河水和表层沉积物中的分配结果.通过连续提取方法可获得无机态的磷,每次获得的无机磷有4种形态:松散吸附态的磷、铝绑定态磷、铁绑定态磷     

Mobilities and leachabilities of heavy metals in sludge with humus soil

Chemical forms of Zn, Ni, Cu, and Pb in municipal sewage sludge were investigated by adding humus soil to sludge and by performing sequential extraction procedures. In the final sludge mixtures, Zn and Ni were mainly found in Fe/Mn oxide-bound (F3) and organic matter/sulfide-bound (F4) forms. For Zn, exchangeable (F1), carbonate-bound (F2), and F3 forms were transformed to F4 and residual forms (F5). For Ni, F1 and F2 forms were transformed to F1, F2, and F3 forms. Both Cu and Pb were strongly associated with the stable forms F4 and F5. For Cu, F2 and F3 forms were major contributors, while for Pb, F3 and F4 forms were major contributors to F5. Humus soil dosage and pH conditions in the sludge were strongly correlated with the forms of heavy metals. Five forms were used to evaluate metal mobilities in the initial and final sludge mixtures. The mobilities of the four heavy metals studied decreased after 28 days. The metal mobilities in the final sludge mixtures were ranked in the following order: Ni > Zn > Cu = Pb. Leaching tests showed that the mobilities of Zn and Ni in lower pH conditions (pH 4) were higher than those in higher pH conditions (pH 8).     

TiO2 nanotubes as solid-phase extraction adsorbent for the determination of polycyclic aromatic hydrocarbons in environmental water samples

An analytical method based on TiO2 nanotubes solid-phase extraction (SPE) combined with gas chromatography (GC) was established for the analysis of seven polycyclic aromatic hydrocarbons (PAHs): acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors a ecting the extraction e ciency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01–0.8 g/mL, repeatability of the extraction (RSD were between 6.7% and 13.5%, n = 5) and satisfactory detection limits (0.017–0.059 ng/mL). The developed method was successfully applied to the analysis of surface water (tap, river and dam) samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.     

湘中锑矿区土壤重金属锑的污染特征

文章研究调查了冷水江锡矿山锑矿区、桃江板溪锑矿区、桃江马迹塘锑矿区、桃江武潭锑矿区、安化符竹溪金锑矿区及安化渣滓溪锑矿区及周围土壤中锑的含量及形态分布.结果表明:各矿区土壤中总锑含量范嗣为185.6-2 081.3 mg/kg,大大超过了土壤中锑的背景值,表明各矿区土壤已被严重污染.采用Tessier逐级提取法对土壤中...     

废弃线路板热解油中酚类物质的提取与分离

将FR-4型废弃线路板热解,并对热解油中含量最多的组分-酚类物质进行分离提取.比较研究线路板热解油的分离提取方法,探索出"碱液处理-酸化-萃取-减压蒸馏"的新方法,对分离出的组分进行GCMS(气质联用)测试.结果显示运用该方法对FR-4型线路板的热解油进行提取分离,得到的总酚占热解油的62.0%,其中苯酚的最高纯度可达...     

海岸带表层沉积物中磷的地球化学特征

通过连续提取法对莱州湾主要入海河流及近岸海域表层沉积物中5种形态磷进行了定量分析.结果表明,近海沉积物自生钙结合磷含量(45.6%)高于河流(37.3%),而铁结合磷(Fe-P)含量(18.2%)却低于河流(31.3%).在近海,可交换或弱结合磷含量和粉砂比例呈正相关,表明该形态磷主要吸附于细粒粉砂.河流沉积物Fe-P与Fe浓度呈显著正相关(P0.01),表明河流沉积物Fe-P分布受沉积物活性铁含量的控制.河口处Fe-P普遍低于相应河流,这可能与海相泥沙输入及河口厌氧区硫酸盐还原或硫化物累积有关.近海沉积物总可提取态磷平均浓度总体呈现出由海洋向河口方向递减的趋势.     

脱水污泥中聚合物的碱提取及其镉吸附效能研究

市政污水处理厂产生的脱水剩余污泥中含有大量的细菌胞外聚合物、胞内聚合物等大分子有机物,是一种良好的生物吸附剂制备原料。以脱水污泥为原料,采用碱提取的方法,对污泥中胞外聚合物与胞内聚合物进行提取,提取得到聚合物吸附剂,分析了聚合物吸附剂中聚合物浓度、核酸浓度随提取剂中NaOH浓度的变化,考察了聚合物吸附剂对水中镉的等温吸附性能。研究结果表明,当NaOH浓度小于0.5 mol/L时,随着提取剂NaOH浓度的升高,得到的提取液中聚合物浓度、核酸浓度逐渐升高。最佳的提取剂中NaOH浓度为0.3 mol/L,该条件下能够充分实现污泥中聚合物的提取。当NaOH浓度高于0.5 mol/L,聚合物中核酸存在一定程度的分解。聚合物吸附剂对水中Cd2+的吸附符合Langmuir模型,NaOH浓度为0.3 mol/L条件下提取得到的聚合物吸附剂的镉饱和吸附容量最大,达1.022 mmol/g。     

废弃钻井液不落地达标处理技术在塔里木油田的应用

废弃泥浆中含有化学添加剂、黏土、钻屑、无机盐及含油物质等,pH值较高,一般存放在井场污池内,若管理不善容易造成环境污染。为减少钻井废弃液对环境的污染,针对塔里木油田自身的地理特征和钻井液类型,选取一套经济有效的废弃钻井液无害化处理工艺开展先导试验,解决了废弃钻井液处理施工难度大、工期长、成本高的问题,达到无害化处理的环保效果。     

黄石市典型农业土壤中重金属污染水平及评价

以黄石市阳新县某大型农场作为研究区,于2012年2月采集8个代表性表层(0~20 cm)土壤样品,采用火焰-原子吸收分光光度法分析了各重金属元素(Cu、Pb、Zn、Cd、Mn、Co)的总量及BCR连续提取法提取土壤中重金属的弱酸态、可还原态、可氧化态和残渣态含量。结果显示,Cu、Pb、Zn、Cd、Mn和Co总量的平均值分别为122.10、141.29、335.53、2.18、2 606.58和128.27 mg/kg,其中Cd超过了土壤环境三级标准限值,Mn具有最强的变异系数,受到外来污染因素的影响最大。通过地积累指数法和潜在生态危害法表明,6种重金属累积程度由高到低依次为CdCoCuPbZnMn,且Cd、Mn为主要生态风险因子。同时由形态分析可知,Cu、Pb、Cd、Zn、Mn和Co的化学形态分布均以残渣态为主,说明该农场土壤中重金属元素比较稳定,不易迁移转化,对生物的毒性较小。     

斯道拉恩索将在美国投资建造生物质可再生材料示范工厂

近日,全球性生物质材料、纸张、包装和林木制品的创想者斯道拉恩索（Stora Enso）宣布,将投资3200万欧元（约合2．53亿元人民币）在美国路易斯安那州雷斯兰市建造一家生物质可再生材料示范性市场开发工厂,以对其新近全资收购的美国生物技术公司Virdia所开发的先进纤维素类生物质提取分离技术进行工业验证,助力斯道拉恩索生物质材料事业部在生物化学和生物质材料领域的发展壮大。