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采用EDTA络合Fe2 的方法改性电-Fenton反应体系降解水中DMP(邻苯二甲酸二甲酯).考察了pH值,Fe2 /EDTA初始浓度,Fe2 与EDTA的物质的量比,不同络合剩体系对DMP降解的影响.结果表明,EDTA络合Fe2 方法改性的电-Fenton反应体系可在中、碱性条件下降解DMP;在pH=7,恒电流6 mA,电解质Na2SO4浓度0.1mol·L-1,曝气速率300 mL·min-1的条件下,处理20 mg·L-1DMP溶液,Fe2 /EDTA的最佳初始浓度为0.5 mmol·L-1,反应3 h,DMP去除率达98%以上.不同的Fe2 与EDTA的物质的量比对DMP的降解效果有不同程度的影响. 相似文献
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本研究采用电-Fenton/三维电极联合技术降解苯酚废水,利用铁改性膨润土(Fe-Bent)作为粒子电极,考察了溶液初始pH、苯酚初始浓度、电流密度、电极间距及电解质浓度等电化学体系操作条件对苯酚降解效果的影响;同时监测了反应过程中铁离子和羟基自由基浓度的变化情况.结果表明,溶液初始pH =3,电流密度125 mA/cm2,苯酚初始浓度100 mg/L,电极间距1.O cm,电解质浓度0.05 mol/L,电解时间180m in时,苯酚的转化率可达到67.53%,COD去除率达57.11%.此时,溶液中铁离子的浓度为6.93 mg/L,沥出的铁离子较少,说明粒子电极较稳定. 相似文献
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以RuO2-TiO2/Ti为阳极,石墨为阴极,构建电-Fenton体系氧化降解水中盐酸四环素(TC),分别考察溶液初始pH、温度、H2O2投加量等因素对TC降解效果的影响及作用机理,并引入Plackett-Burman法筛选影响电-Fenton降解TC的显著单因素。结果表明:当TC浓度为100μmol/L时,各单因素试验的最佳条件为pH=3、温度为30℃、H2O2投加量为10 mmol/L、电流强度为0.5 A、H2O2/Fe2+摩尔比为16:1、电解质浓度为0.1 mol/L、极板间距为2.5 cm,其中溶液初始pH、电流强度与电解质浓度为该电-Fenton氧化体系下降解TC的显著单因素。 相似文献
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文章采用电化学方法合成了锌/聚苯胺/碳纳米管纳米复合物。通过场发射扫描电子显微镜(FE-SEM)和X射线衍射(XRD)对产物的形貌和晶相进行了表征,结果表明:锌纳米粒子均匀的分散在碳纳米管表面。该复合物修饰充蜡石墨电极对过氧化氢有优异的电催化性能,明显地降低了过氧化氢的还原超电势。在磷酸缓冲溶液(pH=7.0)中,过氧化氢的还原电流与浓度在1×10-4~0.03M范围内呈现良好的线性关系,检测限达到9.8×10-7M,相关系数0.993。 相似文献
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生物炭所释放的溶解性有机物(DOM)可能会与污染物相互作用,但DOM的组分及其在生物炭吸附过程中的影响机制尚不清楚。研究对不同热解温度制备的生物炭释放的DOM进行表征,分析其组分和理化性质,通过吸附动力学和吸附等温试验探究DOM在生物炭吸附RhB的过程中的影响机制。结果表明,热解温度和生物质原料均会影响DOM的组分,低温生物炭(300℃)比高温生物炭(500℃和700℃)能释放出更多的DOM,玉米秸秆生物炭的DOM释放量高于松木锯末生物炭,低温生物炭释放的DOM主要组分为富里酸类物质和腐植酸类物质,且其极性指数与生物炭相反。吸附试验表明,DOM的添加延长了酸改性生物炭对罗丹明B(RhB)的吸附平衡时间(90 min→210 min),同时也大大降低了酸改性生物炭对RhB的吸附量(ACS300:7.86 mg/g→2.26 mg/g; APS300:6.41 mg/g→1.61 mg/g),DOM可以与RhB形成络合物(吸附率:14.29%~30.77%),从而抑制其在生物炭上的吸附。此外,还发现DOM的富里酸类和腐植酸类含量与生物炭的吸附量呈负相关。因此,DOM释放量越多,生物炭对Rh... 相似文献
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The removal of the anthraquinone dye Alizarin Red S (AR) has been investigated by electro-Fenton process using a commercial graphite-felt to electrogenerate in situ hydrogen peroxide and regenerate ferrous ions as catalyst. The effect of operating conditions such as applied current, catalyst concentration, and initial dye content on AR degradation has been studied. AR decay kinetic, the evolution of its oxidation intermediates and the mineralization of the aqueous solutions were monitored during the electrolysis by UV–Vis analysis and TOC measurements. The experimental results showed that AR was completely removed by the reaction with OH radicals generated from electrochemically assisted Fenton's reaction, and the decay kinetic always follows a pseudo-first-order reaction. Applying a current of 300 mA and with catalyst concentration of 0.2 mM Fe2+, 95% of the initial TOC was removed in 210 min of electrolysis, meaning the almost complete mineralization of the organic content of the treated solution. 相似文献
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The aim of this work was to degrade pharmaceuticals such as amoxicillin (AMX), ceftriaxone (CTX), and Telebrix (TLX) by electro-Fenton (EF) process using a dimensionally stable anode (DSA) cathode, Pt-RuO2-IrO2 (PRI). For this purpose, the optimal conditions of degradation, the pseudo-first-order kinetics, the current efficiency, the electrochemical energy consumption (EEC), and the energy cost have been investigated. A spectrophotometric analysis technique has been developed. It is a simple, fast, linear, reliable, and selective technique with LOD = 0.013 g/L and LOQ = 0.04 g/L. The optimum working conditions determined are: Fe2+ = 0.2 mM, pH = 3, j = 20 mA/cm2, and (Pt, PRI) as electrode pair. Under these conditions, the EF process leads to a conversion of the parent compound. In addition, the degradation of compounds by EF follows pseudo-first-order kinetics. The EEC for the degradation of 1 kg COD of an organic compound is 99.48, 66.86, and 50.32 kWh kg COD−1 for AMX, CTX, and TLX respectively. The energy cost for processing these compounds is $4.92 (AMX), $10.03 (CTX), and $7.55 (TLX) with current efficiencies between 26% and 51%. Ultimately, the EF process using PRI at the cathode can be used for the treatment of real wastewater from health centres under optimal conditions. 相似文献
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采用粉末冶金法制备了碳纳米管增强环氧/石墨复合材料,并研究了酸洗处理对复合材料弯曲强度、硬度和导电性能的影响。结果表明:与未处理碳纳米管相比,酸处理的碳纳米管增加了环氧/石墨复合材料的弯曲强度和硬度,降低了电阻率。酸处理的碳纳米管增强环氧/石墨复合材料的弯曲强度达到21.9MPa,比未添加碳纳米管时提高了近22%;同时复合材料的硬度达到最大值21.7HS,比未添加碳纳米管时提高了近10%;复合材料的电阻率达到了最小值45036μΩ·cm,比未添加碳纳米管时复合材料的电阻率降低了近17%。 相似文献
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采用浸渍-高温煅烧法制备了Fe3O4/石墨毡复合电极,联合阴极电Fenton和阳极氧化法降解聚丙烯酰胺(PAM)。以CODCr和溶液的相对粘度为指标,分别比较阴极电Fenton法、阳极氧化法及联合法对PAM的降解性能。与单一方法相比,联合法对PAM表现出强化降解效果,降解后溶液的CODCr降低了45.6%,相对粘度由2.19降低到1.04。采用凝胶渗透色谱(GPC)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱分析(XPS)对PAM的降解产物进行表征分析。结果表明,在降解过程中PAM的碳主链缩短,侧链基团大量脱落,并有醚键生成。据此推测PAM在电催化氧化中的降解机理为碳主链的断裂与重新缩合的过程,因此,PAM降解产物中仍存在部分高分子聚合物。所生成的聚合物具有较强的可生化降解性,可被好氧活性污泥进一步降解。 相似文献
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研究了氧化锆/碳纳米管复合材料制备的工艺条件。通过XRD、BET、TEM和Zeta电位的测试结果分析水热温度、水热时间、表面活性剂、pH等因素对产物的影响,确定了较佳的工艺条件:水热温度为180 ℃、水热时间为11 h、pH=9.5。通过TEM和Zeta电位分析可知,加入表面活性剂十六烷基三甲基溴化铵(CTBA)时,碳纳米管表面与氢氧化锆胶体带异种电荷,相互吸附,氧化锆颗粒能均匀覆盖于碳材料上,效果较好。 相似文献
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电芬顿技术作为先进氧化技术的一种,基于电化学原理间接性地产生·OH自由基,可以高效快速地去除水中的有机污染物。碳纤维类材料因其比表面积大、密度低、耐腐蚀等优点而被常用作电芬顿体系的电极材料。本文首先介绍了电芬顿技术的基本原理,对近年来碳纤维类材料用于电芬顿电极的研究现状进行了归纳总结,分析了碳纤维材料用于电芬顿电极时的改性手段及应用方式。着重分析了其用于电芬顿阴极时的改性机理与改性方式,并指出了其应用优势与局限性。同时也对碳纤维类材料在电芬顿阳极的应用进行了总结。最后,针对碳纤维类材料用于电芬顿体系时的产业化问题、能耗问题、电极的多功能化等问题进行了分析和展望,为碳纤维类材料应用于电芬顿体系的深入研究提供参考。 相似文献
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Bin Ji Yaorong Shu Yuexin Li Jiale Wang Yuting Shi 《Chemical Engineering Communications》2019,206(6):708-715
Starch coated nanoscale zerovalent iron (S-nZVI) was immobilized in activated carbon (AC) and its Cr (VI) removal characteristics were studied. Macroscopic evidence and mechanism analysis proved that S-nZVI and AC were closely linked and mutual complementary. Different factors including pH of the original solution, reaction time, and mass ratio (S-nZVI@AC/Cr =10:1, 20:1, 30:1, 50:1, 60:1, 70:1) were studied to analyze the removal rate. Results showed that the removal rate of Cr (Ⅵ) could reach 99.96% under the condition of pH of 5, and temperature =25?°C, when the mass ratio of S-nZVI@AC/Cr was 60:1. The removal of Cr(Ⅵ) by S-nZVI@AC followed pseudo-second-order kinetics. X-ray diffraction (XRD) resulted demonstrate that S-nZVI@AC existed in a Fe3C state before reaction and in a Fe(III) state after reaction. XPS (X-ray photoelectrons spectroscopy) analysis suggested that the mechanism of Cr (VI) removal by S-nZVI@AC is adsorption and reduction. S-nZVI@AC might be a potential composite material for the purification and detoxification of Cr (VI) in water because of its efficiency and stability. 相似文献
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以聚己内酯(PCL)和碳纳米管(CNTs)为主要材料,采用熔融共混制备PCL/CNTs复合材料。随着CNTs含量增加,以直径为10 nm的CNTs(简称CNTs10)制备的PCL/CNTs10复合材料的拉伸强度先增加后降低,以直径为5 nm的CNTs(简称CNTs5)制备的PCL/CNTs5复合材料的拉伸强度先减小后增大,断裂伸长率先降低后增加,体积电阻率逐步降低。CNTs含量相同时,PCL/CNTs5复合材料的体积电阻率小于PCL/CNTs10;CNTs5含量分别为12%和14%时,复合材料的体积电阻率分别为0.92Ω·cm和0.52Ω·cm。扫描电子显微镜分析发现,随着CNTs含量增加,复合材料表面暴露的CNTs5数量逐渐增多,当CNTs10含量≥12%和CNTs5含量≥10%时出现一定的团聚。CNTs5含量为12%的复合材料综合性能最佳,其体积电阻率为0.92Ω·cm、拉伸强度为26.4 MPa、断裂伸长率为267.7%、撕裂强度为46.0 N/cm;在3.7 V直流电压下通电12 min,可从28℃上升到36℃,20 min后达到38℃,随后温度缓慢上升,该复合材料在热敷保健和医疗器械领域具有良好的应用前景。 相似文献