利用芬顿试剂处理硝基苯类生产废水的研究

硝基苯类物质生产废水中含有大量的硝基苯类衍生物 ,属难生物降解类化合物。本研究利用芬顿试剂对该废水进行处理 ,废水的CODcr、硝基苯含量 (NB)及色度的去除率分别达到 60 %、90 %和 82 %以上 ,废水的可生化性得到较大幅度的提高 ,为后续处理创造了条件     

富氧空气—乙炔火焰原子吸收法测定水样中锶

研究了富氧空气-乙炔火焰原子吸收光谱法测定锶的方法,优化了实验条件,选择了最佳的观察高度、氧气流量和乙炔流量,研究了有机试剂的增感作用,0.5%的磺基水杨酸可以提高测定的灵敏度约40%,并可很好的抑制共存离子的干扰,方法的检出限为4ng/mL,该法快速、简便、准确,适合一般水样中痕量锶的测定。     

Fenton法处理卫生填埋渗滤液——从模型放大到中试的问题初探

在中试厂中进行了Fenton法处理卫生填埋渗滤液的试验,以检验根据小试结果得出的统计模型。对三种不同渗滤液的试验发现,COD去除率与模型推出的几种最佳操作条件无关,三种渗滤液的COD去除率分别为35.0±2.2%、42.1±1.0%及50.6±5.6%。这表明不仅中试结果和模型预测(>80%)之间存在较大的差异,而且不同渗滤液的处理程度也存在一定的差异,其中一个原因是各种渗滤液的组分各有差异,因此不能用一种渗滤液的处理结果去预测其它渗滤液。而中试时较低的反应温度是造成试验结果和模型之间存在差异的另一个原因。     

地方性氟中毒环境地球化学病因的探讨

 氟中毒的发生与饮用水中氟离子的含量成正相关，但发病率的轻重又受到钙、镁离子的控制。研究表明：我国南方氟病地区青少年氟斑牙的发生，并非完全由煤烟氟污染玉米所致，而与南方平均气温高，病区人群长期大量饮用含氟和钙、镁离子偏低的水有关，特别是很少食用煤烟氟污染玉米的城市，这种相关性显得更加明显。     

新型杂环三氮烯类光度试剂与镍的显色体系研究

光度法检测微量镍发展的核心是制备高灵敏的显色剂,而杂环三氮烯类试剂由于其显色反应的灵敏度高、选择性好,是热点研究方向。本文以新合成的1-(偶氮苯基)-3-(3-硝基-2-吡啶)-三氮烯(简称AB-NPT)为显色剂,研究了它与镍的高灵敏显色体系,结果表明:在pH值为10.8~11.6范围内Na2B4O7-NaOH的缓冲溶液中,ABNPT在非离子表面活性剂Tween-100存在下与镍形成红色稳定的配合物,其最大吸收波长为535 nm。该显色体系大大提高了测定方法的选择性和抗干扰性,优于其它光度法测镍。采用此法用于矿样中微量镍的测定,结果令人满意,有较强的应用背景和社会效益。     

Interaction between peat, humic acid and aqueous metal ions

Analysis of peat samples from four regions of the British Isles indicates that the concentrations of Al, Pb and common transition metals tend, as expected, to be higher in regions subject to industrial pollution, but that the concentrations of the nontransition metals Na, K, Mg, Ca and Zn tend to be higher in regions remote from industrial pollution. Humic acids were extracted from the most polluted and least polluted of the peat samples and some characteristics of these acids were compared with those of two commercial acids. Values for stability constants of complexes formed between humic acids extracted from peat and Cu²⁺, Zn²⁺ or Pb²⁺ have been obtained by an ionexchange equilibrium method. Of the three metal ions examined, Pb²⁺ was found to form the most stable humic acid complexes, followed by Cu²⁺: this order agrees with the findings of Irving and Williams and of Bunzl. Implications to the binding of actinide and other heavy metal ions in aqueous humic acid are discussed.     

萃取法处理萤光废水

采用萃取法处理萤光废水，最佳萃取工艺条件如下：ｐＨ为１，废水：萃取剂：稀释剂为２０：２：５。在此工艺条件下，萤光废水ＣＯＤ去除率可达９１％－９８％，色度去除率达９９．８％。萃取剂可再生回用，在萃取相中按萃取剂（包括络合物）的量加入等体积的浓度为２０％的ＮａＯＨ溶液，在９５－１０５℃加热回流５－１０ｍｉｎ，即可使萃取剂得到再生。     

Plant uptake and transport models for neutral and ionic chemicals

BACKGROUND: Models for predicting uptake and transport of chemicals in plants are applied in pesticide design, risk assessment, and environmental biotechnology. OBJECTIVE: This review considers the theoretical basics of the most popular models, and discusses what they have in common. The line is drawn between models for neutral compounds, and models for weak and strong electrolytes. MAIN FEATURES: Neutral Compounds. Neutral compounds undergo only very few processes inside plants (lipophilic interactions, metabolism), in contrast to weak electrolytes. The models developed for neutral compounds are widely applied in the risk assessment of environmental contaminants, but are not of much use for weak electrolytes, such as pesticides. Weak electrolytes. A very important process for weak electrolytes is the 'ion trap', which traps chemicals that dissociate inside plant cells. This is considered in the popular models of Kleier, Satchivi and Briggs. Other relevant processes for electrolytes are electrophilic interactions, speciation and complex formation. None of the currently used models considers these processes. CONCLUSIONS: The accuracy of models for neutral compounds is satisfactory, but the prediction of electrolyte behavior inside plants is still quite difficult due to gaps in knowledge.     

Two-stage chemical fractionation method for the analysis of elements and non-volatile inorganic ions in PM10 samples: Application to ambient samples collected in Rome (Italy)

A two-stage micro-analytical scheme for the determination of metals and ions in atmospheric particulate matter collected on only one Teflon filter was developed. In the first stage the collected particles are chemically fractionated for their solubility in a pH-buffered extracting solution; in the second stage the residue is mineralised. The major non-volatile inorganic ions (Cl⁻, NO₃⁻, SO₄²⁻, Na⁺, NH₄⁺, Ca²⁺, Mg²⁺) are determined in the first fraction by ion-chromatography (IC), while metals and metalloids (Al, As, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, S, Sb, Se, Si, Ti, V, Zn) are determined in both the acetate extractable and the mineralised residual fractions by inductively coupled plasma optical emission spectroscopy (ICP-OES).The procedure was applied to ambient 24-h PM₁₀ samples collected on Teflon filters during two field campaigns carried out at two sites in the area of Rome (Italy). The variations in the chemical composition of the collected particles during the two periods were interpreted in the light of the dilution properties of the lower atmosphere and of the back-trajectories of the air masses. The difference in the results between the two locations was interpreted in the light of their proximity to the emission sources. It was found that the acetate extractable and the mineralised residual fraction of some metals exhibit a different temporal pattern, suggesting the existence of different emission sources of the two fractions.     

焦粉成型技术

冶金、化工、电石生产企业 ,因生产工艺要求需要将大块的焦炭破碎成一定粒度的块焦 ,破碎过程要产生2 0 %— 2 5 %的焦粉。本文针对目前工业废弃焦粉再利用问题 ,通过深入调查 ,反复试验 ,取得了很好的效果。为冶金、化工、电石生产企业废弃焦粉成型再利用找到一条切实可行的方法