微波强化Fenton体系处理制药废水研究

为了实现高浓度制药废水的处理,采用微波强化Fenton氧化体系对污水进行预处理,考察了微波功率、微波辐照时间、催化剂用量和氧化剂用量对高浓度有机废水中有机物去除效果的影响。来水COD 39 760 mg/L,B/C为0.254,控制微波功率为200 W、微波辐照时间11 min,加入0.6 mol/L的Fe(NO_3)_3催化剂、30%H_2O_2 4 mL/L氧化剂,COD去除率可达62.41%,B/C由0.254升至0.619。实现有机物去除,提高污水可生化性。     

A critical review on the technique and mechanism of microwave-based denitrification in flue gas

Microwave radiation has received extensive attention due to its significant thermal and non-thermal effects, and the development of MW-based denitrification in flue gas has become one of the most promising methods to avoid the defects of ammonia escape, high temperature and cost in traditional SCR. This review introduces the thermal and non-thermal effects of microwaves and divides MW-based denitrification methods into MW reduction and oxidation denitrification, systematically summarizes these denitrification methods, including MW discharge reduction, MW-induced catalytic reduction using active carbon, molecular sieves, metal oxides (transition metals, perovskites, etc.), MW-induced oxidation denitrification with and without additional oxidant, and discusses their removal pathway and mechanism. Finally, several research prospects and directions regarding the development of microwave-based denitrification methods are provided.     

Effects of acidifying reagents on microwave treatment of dairy manure

Dairy manure, acidified using organic acids (acetic, oxalic, and citric acid) were treated with microwave enhanced advanced oxidation process (MW/H₂O₂-AOP). The effect of a mixture of oxalic acid and commonly used mineral acids (sulfuric and hydrochloric acid) on MW/H₂O₂-AOP was also examined. Substantial amounts of phosphorus were released under MW/H₂O₂-AOP, regardless of organic acid or mineral acid used. All three organic acids were good acidifying reagents; however, only oxalic acid could remove free calcium ion in the solution, and improve settleability of dairy manure. The MW/H₂O₂-AOP and calcium removal process could be combined into a single-stage process, which could release phosphate, solubilize solids and remove calcium from dairy manure at the same time. A mixture of oxalic acid and mineral acid produced the maximum volume of clear supernatant and had an ideal molar ratio of calcium to magnesium for effective struvite (magnesium ammonium phosphate) crystallization process. A single-stage MW/H₂O₂-AOP would simplify the process and reduce mineral acid consumption compared to a two-stage operation. The results of a pilot scale study demonstrate that MW/H₂O₂-AOP is effective in treating manure and recovering resource from dairy farms.     

SJ—20型环境生物样品微波溶样器的研制

研制出了SJ—20型环境生物样品微波溶样器,测定了溶样器的耐压情况,并在实际生物和食品样品的测定中进行了初步应用.结果表明,该溶样器安全可靠,消化速度快,消解完全,对环境基本无污染.     

Photocatalytic defluorination of perfluorooctanoic acid by surface defective BiOCl: Fast microwave solvothermal synthesis and photocatalytic mechanisms

There is an urgent need for developing cost-effective methods for the treatment of perfluorooctanoic acid(PFOA)due to its global emergence and potential risks.In this study,taking surface-defective BiOCl as an example,a strategy of surface oxygen vacancy modulation was used to promote the photocatalytic defluorination efficiency of PFOA under simulated sunlight irradiation.The defective BiOCl was fabricated by a fast microwave solvothermal method,which was found to induce more surface oxygen vacancies than conventional solvothermal and precipitation methods.As a result,the asprepared BiOCl showed significantly enhanced defluorination efficiency,which was 2.7 and33.8 times higher than that of BiOCl fabricated by conventional solvothermal and precipitation methods,respectively.Mechanistic studies indicated that the defluorination of PFOA follows a direct hole(h~+)oxidation pathway with the aid of·OH,while the oxygen vacancies not only promote charge separation but also facilitate the intimate contact between the photocatalyst surface and PFOA by coordinating with its terminal carboxylate group in a bidentate or bridging mode.This work will provide a general strategy of oxygen vacancy modulation by microwave-assisted methods for efficient photocatalytic defluorination of PFOA in the environment using sunlight as the energy source.     

Microwave and Fenton's reagent oxidation of wastewater

We compared two H₂O₂ oxidation methods for the treatment of industrial wastewater: oxidation using Fenton's reagent [H₂O₂/Fe(II)] and microwave irradiation. Both methods were applied to the treatment of synthetic phenol solutions (100 mg L⁻¹) and of an industrial effluent containing a mixture of ionic and non-ionic surfactants at high load (20 g L⁻¹ of COD). The effects of initial pH, initial H₂O₂ concentration, Fenton catalyst amount and irradiation time were assessed. According to the oxidation of phenol, it has been found that the oxidation by Fenton's reagent is dependent on the pH, contrary to the microwave system, which is not influenced by this parameter. For both systems, a limiting amount of oxidant has been found; above this point the oxidation of phenol is not improved by a further addition of peroxide. The oxidation of the industrial surfactant effluent has only been successful with the Fenton's reagent. In this case, large amounts of ferrous ions are necessary for the precipitation of the ionic surfactants of the effluent, followed by the oxidation of the non-ionic constituents of the solution. Electronic Publication     

微波辐射合成酪氨酸席夫碱及其光度法测定蔬菜中钴的研究

在微波辐射下 ,合成酪氨酸与桑色素席夫碱 ,该方法有很多优点 .缩短反应时间 ,仅 1 0min完成反应 ,产率在 88.5 %～ 90 .1 % ,该席夫碱应用于光度法测定蔬菜中钴的含量 .实验表明 ,钴与酪氨酸席夫碱形成 1∶1络合物 ,最大吸收波长λmax =670nm ,摩尔吸光系数为 5 .2× 1 0 4L·mol- 1 ·cm- 1 ,方法对于测定蔬菜中的钴 ,结果较满意 .     

微波消解在样品前处理中的应用

本文采用微波消解前处理方法对大米、土壤、人发等样品进行前处理,对样品中所含重金属进行测定,其中微波消解前处理方法具有空白小、准确度高、相对偏差小,是较为理想的前处理方法.     

微波技术在水污染治理中的应用

对当前微波辐射技术在水污染治理领域的应用和研究状况进行了综述，着重介绍了微波辐射机理、特点及其在废水处理、材料制备等方面的应用，并展望了微波技术在环保领域的应用前景。     

微波消毒技术在医疗废物集中处理工程中的应用

通过对微波消毒机理的研究,根据其节能、快速、污染小、消毒效果彻底等特点,提出了微波消毒技术适用于医疗废物集中处置工程,并且列举国际应用实例为证。通过对医疗废物微波处理技术标准、微波消毒适用范围、系统组成、安全与防护等方面对我国已颁布的《医疗废物微波消毒集中处理工程技术规范》(试行)(HJ/T229-2006)主要内容作了客观阐述,提出在我国目前《全国危险废物和医疗废物处置设施建设规划》实施的情况下,医疗废物微波消毒处理法将与其它几种非焚烧处置法,共同作为医疗废物焚烧法的合理补充技术在中国应用,将有效地推进中国医疗废物处理进程。