高氯废水化学需氧量分析方法综述

对高氯废水化学需氧量分析方法进行归纳和综述。常用的高氯废水化学需氧量分析方法有氯气校正容量法、降氯密闭消解分光光度法以及高温氧化总有机碳系数换算法等。其中氯气校正容量法操控要求较高,分析耗时较长,不适用于大批量样品同步分析;降氯密闭消解分光光度法灵敏度高,但在降氯过程中增加了重金属盐硫酸汞的用量,分析成本较高,易产生二次污染,且对样品的均质性要求较高;高温氧化总有机碳系数换算法操作便捷、抗干扰能力强,但是换算系数易随不同来源、不同组分的样品发生波动,数据可比性需要通过实验验证。经过梳理归纳,明确各种分析方法的特点和适用范围,为研究人员选择合适的分析方法或进一步开展相关的方法研究提供参考。     

Synthesis of IONP's decorated graft copolymers and study of their magnetic force–induced wastewater treatment

Our work is focused on facile synthesis and modification of amylopectin‐grafted block copolymers by using reversible addition?fragmentation chain transfer (RAFT) polymerization technique. This technique yields polymers with controlled molecular weight and low polydispersity indexes and is feasible with a wide range of monomers. Five different grades of amylopectin‐grafted polymethacrylic acid and polyacrylamide block copolymers have been synthesized via RAFT, by varying the amount of acrylamide employing amylopectin‐based macro chain transfer agent. Graft copolymers have been upgraded as smart responsive graft copolymers, through the incorporation of iron oxide nanoparticles (IONPs) via condensation reaction. The polymeric materials have been extensively characterized by energy‐dispersive X‐ray analysis, Fourier transform infrared spectroscopy, proton magnetic resonance spectroscopy, scanning electron microscopy, ultraviolet‐visible spectroscopy, gel permeation chromatography, transmission electron microscopy, thermogravimetric analysis, and X‐ray diffraction analysis. Normal and responsive graft copolymers have been studied for removal of model contaminant (kaolin), and responsive graft copolymers have been used to remove methylene blue dye (without using any adsorbent) from water by applying external magnetic field. The upgraded block copolymers have shown best performance in wastewater treatment.     

Antibiotics Separation with MXene Membranes Based on Regularly Stacked High‐Aspect‐Ratio Nanosheets

The uncontrolled release of antibiotics and pharmaceuticals into the environment is a worldwide increasing problem. Thus, highly efficient treatment technologies for wastewater are urgently needed. In this work, seven kinds of typical antibiotics (including water and alcohol soluble ones) are successfully separated from the corresponding aqueous and ethanolic solutions using highly regular laminated membranes. Our membranes are assembled with 2–4 μm titanium carbide nanosheets. The solvent permeance through such titanium carbide membrane is one order of magnitude higher than that through most polymeric nanofiltration membranes with similar antibiotics rejection. This high flux is due to the regular two‐dimensional (2D) structure resulting from the large aspect ratio of titanium carbide nanosheets. Moreover, the electrostatic interaction between the surface terminations and the antibiotics also affects the rejection and enhances the antifouling property. Such 2D titanium carbide membranes further broaden the application scope of laminated materials for separation and purification of high value added drugs in academia and industry.     

三相流化床电极反应器深度处理制浆废水

应用三相流化床电极反应器(新型电化学反应器)处理制浆废水.研究了曝气量、槽电压、溶液pH值及FeSO4浓度等因素对电解效果的影响.结果表明,该反应器深度处理制浆废水的最佳工艺条件为:槽电压20 V,曝气量为0.3 m3.h-1,FeSO4浓度为1000 mg.L-1,pH值≈2.5,反应时间为90 m in时COD去除率为70.1%.     

Beta-Cyclodextrin-Decorated Magnetic Activated Carbon as a Sorbent for Extraction and Enrichment of Steroid Hormones (Estrone, β-Estradiol,Hydrocortisone and Progesterone) for Liquid Chromatographic Analysis

A β-cyclodextrin-decorated magnetic activated carbon adsorbent was prepared and characterized using various analytical techniques (X-ray diffraction (XRD), scanning electron microscopy–electron diffraction spectroscopy (SEM-EDS) and transmission electron microscopy (TEM)), and the adsorbent was used in the development of a magnetic solid-phase microextraction (MSPE) method for the preconcentration of estrone, β-estradiol, hydrocortisone and progesterone in wastewater and river water samples. This method was optimized using the central composite design in order to determine the experimental parameters affecting the extraction procedure. The quantification of hormones was achieved using high-performance liquid chromatography equipped with a photodiode array detector (HPLC-DAD). Under optimum conditions, the linearity ranged from 0.04 to 300 µg L⁻¹ with a correlation of determinations of 0.9969–0.9991. The limits of detection and quantification were between 0.01–0.03 and 0.033–0.1 µg L⁻¹, with intraday and interday precisions at 1.1–3.4 and 3.2–4.2. The equilibrium data were best described by the Langmuir isotherm model, and high adsorption capacities (217–294 mg g⁻¹) were obtained. The developed procedure demonstrated high potential as an effective technique for use in wastewater samples without significant interferences, and the adsorbent could be reused up to eight times.     

微波无极紫外光助双氧水处理活性艳红X-3B染料废水研究

活性艳红X-3B(C.I.ReactionRed 2)是一种单偶氮染料,其应用范围广泛,可用于棉、粘纤、涤/棉、锦纶、蚕丝、羊毛、锦/粘等织物的染色和丝绸的印花,因此其废水量大且色度深。目前染料废水的生物处理方法脱色效果差、占地面积大、处理周期长,传统的物理法和化学法也存在着成本高、不能彻底矿化染料分子等缺点。近年来发展起来的光化学处理染料废水的方法及各种光化学组合技术日益受到人们关注,但其中使用的普通紫外灯存在使用寿命短、启动慢、发光不稳定、电极材料易损等缺点[1],致使光化学方法处理废水的成本很高。本文利用微波产生的高频…     

Influence of Water Treatment and Wastewater Treatment on the Changes in Residues of Important Elements in Drinking Water

Drinking water is the essential medium for food production, and is also needed for direct consumption; while it must be free of harmful substances, it also must have a composition that is beneficial to health. The aim of this study was to evaluate the influence of water and wastewater treatment on reducing the concentrations of zinc (Zn), nickel (Ni), iron (Fe), manganese (Mn), copper (Cu), lead (Pb), and arsenic (As) in the Western Pomerania Voivodeship in Poland. The research was carried out in 2017–2019. The analysis was performed with inductively coupled plasma atomic emission spectrophotometry (ICP-AES). The concentrations of trace elements in drinking water were below maximum acceptable concentrations (MACs). Reductions in the most dangerous elements during water treatment fluctuated from 48.5% (As) to 97% (Pb). Wastewater treatment reduced the concentrations of analyzed elements by a range of 28.6 to 60.8%, and the most toxic elements (Pb and As) by over 50%. Trace element concentrations in treated wastewater were below MAC values, and ranged from 1.15% (Pb) to 6.23% (As) of MACs for toxic elements. The concentrations of both essential elements (Zn, Ni, Fe, Mn, Cu) and toxic elements (Pb, As) in drinking water were below the MACs. Water treatment had a significant (p < 0.05) effect on decreasing trace element concentrations.     

Impact of High-Pressure Homogenization on the Cell Integrity of Tetradesmus obliquus and Seed Germination

Microalgae have almost unlimited applications due to their versatility and robustness to grow in different environmental conditions, their biodiversity and variety of valuable bioactive compounds. Wastewater can be used as a low-cost and readily available medium for microalgae, while the latter removes the pollutants to produce clean water. Nevertheless, since the most valuable metabolites are mainly located inside the microalga cell, their release implies rupturing the cell wall. In this study, Tetradesmus obliquus grown in 5% piggery effluent was disrupted using high-pressure homogenization (HPH). Effects of HPH pressure (100, 300, and 600 bar) and cycles (1, 2 and 3) were tested on the membrane integrity and evaluated using flow cytometry and microscopy. In addition, wheat seed germination trials were carried out using the biomass at different conditions. Increased HPH pressure or number of cycles led to more cell disruption (75% at 600 bar and 3 cycles). However, the highest increase in wheat germination and growth (40–45%) was observed at the lowest pressure (100 bar), where only 46% of the microalga cells were permeabilised, but not disrupted. Non-treated T. obliquus cultures also revealed an enhancing effect on root and shoot length (up to 40%). The filtrate of the initial culture also promoted shoot development compared to water (21%), reinforcing the full use of all the process fractions. Thus, piggery wastewater can be used to produce microalgae biomass, and mild HPH conditions can promote cell permeabilization to release sufficient amounts of bioactive compounds with the ability to enhance plant germination and growth, converting an economic and environmental concern into environmentally sustainable applications.     

纳米TiO2-SnO2介孔材料的制备及其对含氰废水的光催化降解性能

以TiCl4和SnCl4为原料,采用直接水解常压液相反应合成出了纳米TiO2-SnO2复合介孔材料.利用XRD和TEM及漫反射谱等对样品进行了表征,并研究了纳米TiO2-SnO2复合介孔材料对含氰废水的光催化降解性能.结果表明,纳米TiO2与SnO2复合后,导致材料的光谱响应拓宽;此种催化剂在日光灯下比在紫外灯下对废水中CN-的降解效果要好.     

应用大孔吸附树脂从农药废水中回收毕克草

毕克草为一种新型除草剂,通常情况下很难被降解,本文利用物理吸附原理通过自行制备的大孔吸附树脂从农药水中对其进行了回收,回收效果良好,同时也达到了废水处理的目的。优化的最佳实验条件:室温下,pH=1.0以及流速为5BV/h时,对COD为15000mg/L的毕克草废水吸附处理后,其出水可达《污水综合排放标准》(GB89—1996)中的一级排放标准;洗脱再生时,室温下,用95%的乙醇洗脱,流速为2BV/h,(即2倍树脂床体积/h)回收率可达98.4%,纯度达93.7%,总流程一次可处理该废水240mL。