Degradation of Nitrobenzene-Containing Wastewater with O_3 and H_2O_2 by High Gravity Technology

Nitrobenzene-containing industrial wastewater was degraded in the presence of ozone coupled with H2O2 by high gravity technology. The effect of high gravity factor, H2O2 concentration, pH value, liquid flow-rate, and reaction time on the efficiency for removal of nitrobenzene was investigated. The experimental results show that the high gravity technology enhances the ozone utilization efficiency with O3/H202 showing synergistic effect. The degradation efficiency in terms of the COD removal rate and nitrobenzene removal rate reached 45.8% and 50.4%, respectively, under the following reaction conditions, viz.： a high gravity factor of 66.54, a pH value of 9, a H2O2/O3 molar ratio of 1：1, a liquid flow rate of 140 L/h, an ozone concentration of 40 rag/L, a H2O2 multiple dosing mode of 6 mL/h, and a reaction time of 4 h. Compared with the performance of conventional stirred aeration mixers, the high gravity technology could increase the COD and nitrobenzene removal rate related with the nitrobenzene-containing wastewater by 22.9% and 23.3%, respectively.

Membrane enhanced COD degradation of pulp wastewater using Cu_2O/H_2O_2 heterogeneous Fenton process

Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction,in particular,with no limitation for the working p H and no production of the sludge.In this work,a combination of catalyst Cu_2O and pore-channel-dispersed H_2O_2is proposed to treat the pulp wastewater.Degradation degree of CODs in the wastewater was up to 77%in the ceramic membrane reactor using Cu_2O powder(2.0 g·L^(-1))and membranefeeding H_2O_2(0.8 ml·L^(-1))within 60 min.Evolution of·OH radical formation in the advanced oxidation process was analyzed with a fluorescent method.Utilization efficiency of H_2O_2was successfully enhanced by 10%with the membrane distributor.Further on,the catalyst recyclability was evaluated in a five-cycle test.The concentration of copper ions being dissolved in the treated water was monitored with ICP.After Cu_2O/H_2O_2(membrane)treatment the effluent is qualified to discharge with COD concentration lower than 15 mg·L^(-1)with regard to the national standard GB25467-2010.

HETERONUCLEAR COMPLEX CONTAINING COPPER-LANTHANIDE ARRAYS: THE SYNTHESIS AND CRYSTAL STRUCTURE OF Ln_2Cu_4L_8 (HL)_4(OH)_2(CIO_4)_4(H_2O)_(10)·2CH_3COCH_3 (Ln = Tb (1), Y (2); HL = 2-Pyridone C_5H_5NO)

Reaction of 2-pyridone, copper acetate and terbium(or yttrium) perchlorate in acetone with the mole ratio 6: 2: 1 results in the formation of heteronuclear complex Ln_2Cu_4L_8 (HL)_4 (OH)_2 (ClO_4)_4 (H_20)_(10) 2CH_3COCH_3(Ln = Tb (1), Y (2)). By recrystallizing (1) in CHCl_3 single crystals were obtained and the structure was determined by four-circle diffractometer. Data showed that the crystal is in space group C2/m with a=27. 454(9)A, b=13, 608A, c=30. 556(11)A, β=99. 89(3)°, v=11245. 7(7. 5)A^3. The structure was solved by a combination of Patterson method and Fourier technique. The final R value is 0. 103. In the structure, four copper and two terbium ions are bridged by 2-pyridone anions to form an essentially octahedral Cu_4Tb_2 core. The terbium atoms are each eight-coordinate and the copper atoms are five-coordinate.

Renewable conversion of coal gangue to 13-X molecular sieve for Cd^(2+)-containing wastewater adsorption performance

Using coal gangue(CG)as raw material,a new type of all solid-waste-based 13-X molecular sieve material was controllably prepared by alkali fusion-hydrothermal method.The synthetic molecular sieve was used as a solid adsorbent to treat Cd^(2+)-containing wastewater,and its adsorption behavior on Cd^(2+)in aqueous solution was studied and analyzed.The microstructure and morphology of the molecular sieve were investigated by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM)and specific surface area analyzer.The results show that the synthesized 13-X molecular sieve has higher Brunauer–Emmett–Teller(BET)specific surface area with higher crystallinity and higher adsorption capacity for the heavy metal Cd^(2+).The adsorption process of Cd^(2+)by molecular sieve conforms to the Langmuir isotherm adsorption equation and Lagergren pseudo-second-order rate equation.Combined with thermodynamic calculation,it can be concluded that the adsorption process is physically monolayer,spontaneous and exothermic.In this study,a low-cost and naturally available synthesis method of 13-X molecular sieve is reported.Combined with its adsorption mechanism for Cd^(2+),it provides a feasible and general method for removing heavy metal ions from coal gangue and also provides a new way for the utilization of coal gangue with high added value.

改性膨润土对废水中Cu^(2+)、Zn^(2+)去除效果的研究

在对钙基膨润土原土进行钠化的基础上,用阴离子表面活性剂十二烷基硫酸钠(SDS)与阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)改性制得了有机改性膨润土。通过对含Cu2+、Zn2+废水处理试验,发现Na-膨润土及有机改性膨润土对Cu2+、Zn2+的吸附符合Langmuir方程,有机改性膨润土比Na-膨润土具有更大的吸附容量。试验对影响Cu2+、Zn2+去除的吸附时间、pH、膨润土用量、温度等因素进行了优化研究。当改性膨润土用量为5.0 g.L-1时,对实际电镀废水中Cu2+、Zn2+去除率分别为97.8%和87.6%。

Cu-Bi_2WO_6的制备及应用于光催化氧化含酚废水的研究

以Bi(NO3)3.5H2O和Na2WO4.2H2O为原料,采用水热法合成了掺杂型可见光催化剂Cu-Bi2WO6,并对其进行X射线粉末衍射(XRD)、紫外-可见漫反射(UV-Vis DRS)、扫描电子显微镜(SEM)表征。结果表明,Cu-Bi2WO6在不同合成条件下呈现多孔微球和纳米片状结构。以苯酚水溶液为目标降解物,研究了在可见光催化作用下Cu-Bi2WO6的催化性能,实验结果表明掺杂型Cu-Bi2WO6具有比纯Bi2WO6更高的催化活性。

重金属捕集剂XMT处理电镀废水中Cu^(2+)的试验研究

以XMT作为重金属离子捕集剂,进行了电镀废水Cu2+的捕集研究,探讨了XMT加入量、pH、絮凝剂加入量及反应时间等因素对Cu2+捕集效率的影响。结果表明,质量分数为10%的XMT加入量2.0 mL、pH=3～12、质量分数为0.01%的PAM絮凝剂加入量1.0 mL、反应时间10～30 min等优化工艺条件下,Cu2+去除率在99%以上,残余Cu2+质量浓度小于0.05 mg.L-1,出水满足GB 21900-2008一级排放要求。

水淬渣-累托石混合吸附剂处理含Cu^(2+)冶金废水的研究

研究了以水淬渣-累托石为吸附剂对含Cu2+的冶金废水进行处理。实验结果表明,在不调节含Cu2+冶金废水pH值的条件下,水淬渣与累托石质量比为3∶1,吸附剂用量为0.03 g/mL,作用时间为20 m in,温度为25℃(常温)时,Cu2+的去除率达99.8%,对Cu2+的吸附容量为0.302 mg/g,处理后的水符合国家污水综合排放标准(GB8978-1996)一级标准。水淬渣-累托石混合吸附剂比水淬渣或累托石单一吸附剂除Cu2+效果要好。

高炉渣对废水中Cu^2+的吸附率和吸附行为

工业固废高炉渣对废水中的重金属离子表现出了较好的吸附能力,为了深入了解高炉渣对Cu^2+的吸附效果,在研究高炉渣的用量、pH、吸附时间和温度对废水中Cu^2+吸附率的影响规律基础上,选取四因素三水平正交设计实验,获得吸附Cu^2+的最佳反应条件,并利用吸附等温模型和吸附动力学探讨高炉渣对Cu^2+的吸附行为.结果表明:高炉渣表面的吸附位点、较大的比表面积以及发达的孔隙结构能够促进Cu^2+的吸附.在高炉渣用量为0.5 g、pH为9、吸附时间为360 min、温度为65℃时,去除率可达99.93%,吸附后溶液中Cu^2+的残余质量浓度小于1 mg/L,达到了国家排放标准.高炉渣对Cu^2+的吸附更符合Langmuir吸附等温模型,吸附动力学过程更符合拟二级动力学方程.

飞灰吸附处理电镀废水中Cu^(2+)的研究

以垃圾焚烧发电厂产生的飞灰为吸附剂,就飞灰对电镀废水中Cu2+的静态吸附特性进行了试验研究,着重探讨了平衡时间、pH值、飞灰剂量、溶液初始浓度等因素对Cu2+吸附效果的影响。结果表明,飞灰吸附处理电镀废水中Cu2+的吸附平衡时间为2h;pH值是影响飞灰吸附废水中Cu2+的重要因素,pH=6时吸附效果最好,对Cu2+的去除率可达到87.01%;飞灰对Cu2+的吸附等温线较好地符合Henry模型和Fre-undlich模型,但不符合Langmuir模型。

SiO_3^(2-)柱撑含Cu类水滑石化合物的合成及其催化苯酚/H_2O_2羟基化反应性能

采用共沉淀法合成了 SiO_3^(2-)柱撑的含 Cu 类水滑石化合物(Cu-HTLcs-SiO_3)。X 射线衍射、透射电子显微镜和傅里叶变换红外光谱表征结果显示,Cu-HTLcs-SiO_3具有类水滑石结构,且层板间距大于 Cu-HTLcs-CO_3;Cu-HTLcs-SiO_3具有较好的网状结构,但其晶粒形貌和纹理特征受 n(Mg):n(Al)和n(SiO_3^(2-)):n(OH)的影响,Cu-HTLcs-SiO_3晶粒间的团聚严重影响其催化活性。以苯酚/H_2O_2羟基化为探针反应时发现,Cu-HTLcs-SiO_3的催化性能优于Cu-HTLcs-CO3,以在 Cu 摩尔分数为22.00%、n(Mg):n(Al)=3 00、n(SiO_3^(2-)):n(OH)=0.50的条件下合成的 Cu-HTLcs-SiO_3为催化剂,苯酚的转化率可达31.2%。

酸改性膨润土处理含Cu^(2+)废水实验研究

用硫酸对天然膨润土进行活化改性制得酸改性膨润土 ,研究了该土处理含Cu2 + 废水的适当条件。结果表明 :Cu2 + 初始浓度为13 .6mg/L时 ,用土量为 8g/L、pH =7、振速 15 0～ 160r/min、吸附时间 3 0min ,酸改性膨润土对Cu2 + 的去除率可达 99.9%。处理后Cu2 +

改性硅藻土处理含重金属Cu^(2+)废水

工业废水中有许多重金属离子如Cu2+等,对环境和人体有巨大的危害,在这些废水排入河流、湖泊之前需要进行一系列的处理,使之不会污染环境和危害人体健康。本文研究了改性天然微孔材料——硅藻土吸附模拟废水中重金属离子Cu2+的吸附作用及影响因素。实验研究表明:吸附过程中硅藻土用量、吸附时间、溶液pH值,是影响硅藻土对重金属离子Cu2+吸附去除的主要因素。其中,pH值是影响吸附的最主要的因素。最佳吸附条件:时间60min,pH值4,用土量0.6g。

有机改性累托石吸附Cu^(2+)的性能研究

累托石经过提纯,与十二烷基二甲基苄基氯化铵(1227)有机改性后对铜冶炼工业废水中Cu2+进行了吸附研究。实验结果表明,在不调节铜冶炼工业废水pH值的条件下,有机改性累托石用量为0.03g/mL,作用时间为30min,温度为25℃,Cu2+的去除率达98.95%,处理后的水符合国家污水综合排放标准(GB8978-1996)一级标准。有机改性累托石比提纯累托石除Cu2+效果要好。

涌泉膨润土吸附废水中Cu^(2+)、Zn^(2+)、Cr^(3+)的试验研究

用山东潍坊涌泉某膨润土厂生产的膨润土对模拟含Cu2+、Zn2+、Cr3+的废水进行了试验研究。结果表明,该膨润土对废水中的Cu2+、Zn2+、Cr3+有较高的去除率,并且吸附速度快、时间短,可作为废水中重金属Cu2+、Zn2+、Cr3+的吸附剂使用。吸附后的膨润土,可用作抗菌材料的添加剂。

电混凝法处理电镀废水中的Cu^(2+)和Zn^(2+)

利用电混凝法处理含Cu2+和Zn2+的电镀废水,系统地考察了电解电压、进水pH值、极板间距、电解时间等因素对废水处理效果的影响,确定了最佳的电解条件。实验结果表明,电混凝法处理的电镀废水出水水质较好。当电压为80 V,pH值为5,电解时间30 min,极板间距为10 mm时,处理后的废水中Zn2+浓度为0.36mg/L,去除率达到97.9%,Cu2+浓度为0.0049 mg/L,去除率达到99.9%,均可达到国家规定的排放标准,且该法运行方便,处理时间短,是较理想的电镀废水处理工艺。

pH对高铁酸钾辅助聚合氯化铝去除废水中Cu^(2+)的影响研究

利用静态试验研究了pH对聚合氯化铝(PAC)、高铁酸钾、高铁酸钾辅助PAC去除废水中Cu2+的影响,并初步探讨了其去除机制。结果表明,PAC、高铁酸钾、高铁酸钾辅助PAC对废水中Cu2+均有较好的去除效果,去除率在70%以上,其中高铁酸钾辅助PAC对Cu2+的去除效果最佳,去除率最大可达94.2%;中性和弱碱性条件下Cu2+的去除率明显高于酸性及强碱性条件,最佳氧化pH与絮凝pH分别为9和8。

Cu-Co/γ-Al_(2)O_(3)催化臭氧氧化深度处理维生素废水研究

为解决维生素C废水经二级生化处理后仍不能达到排放标准的问题,以γ-氧化铝为载体,采用化学浸渍法工艺制备出一种高效稳定的Cu-Co/γ-Al_(2)O_(3)催化剂,构成臭氧催化氧化体系。采用XRD、BET、SEM对催化剂进行表征,并探究不同条件下对维生素C废水深度处理效果的影响。结果表明,在反应初始溶液pH=9、臭氧浓度20 mg/L、臭氧流量1 L/min、催化剂投加量为16 g/L、过氧化氢投加量6 mL/L、在反应时间持续90 min的条件下,COD去除率、UV 254去除率、TOC去除率分别达到83.25%,92.14%,79.39%。EPR测试表明臭氧催化氧化体系遵从羟基自由基作用机理,Cu-Co/γ-Al_(2)O_(3)催化剂重复使用10次后,COD去除率、UV 254去除率、TOC去除率仍达到76.37%,86.15%和74.29%,且负载金属离子浸出维持在较低水平,表明该催化剂是一种优异稳定的非均相臭氧催化剂。

不同负载下热再生氨电池产电及Cu^(2+)去除特性

热再生氨电池(thermally regenerative ammonia-based battery,TRAB)在利用低温废热产电的同时去除Cu^(2+),在含铜电镀废水的处理及资源回收方面具有独特的优势和良好的应用前景。而作为关键运行参数之一的负载不但影响电化学反应速率和产电性能,而且还会对Cu^(2+)去除效果产生影响。此外,氨渗透现象的存在极大地影响了Cu^(2+)的去除效果。本文在不同负载条件下对电池进行批次放电,探究负载对电池的产电特性及铜离子去除率的影响,利用循环伏安法探究不同氨浓度条件下阴极发生的反应。对产电后的阳极液进行热再生,探究不同再生温度对热再生过程、电池功率及Cu^(2+)去除率的影响。研究结果表明,随着负载的降低(电流增大),电池的产电量得到提升,批次处理所需的时间大幅缩短。并且较小的负载可以有效降低阴极氨渗透量,减弱副反应的发生,从而提升阴极库仑效率,因此获得较高的Cu^(2+)去除率。当负载为1Ω时获得了较大的产电量(350C),且处理时间缩短为2.1h,使得废水中Cu^(2+)的去除率达到80.5%。热再生过程对下一批次电池性能和阴极Cu^(2+)去除有重要影响,一定范围内提升再生温度有利于热再生过程的进行。

羧基碳纳米管钛网电极去除工业废水中Cu^2+研究

用羧基单壁碳纳米管钛网电极(SWCNTs-COOH@Ti-mesh)为阴极,空白钛网(Ti-mesh)为阳极,去除模拟工业废水中的Cu^2+。考察了电极组合、溶液pH、应用电压和电解质浓度对Cu^2+去除的影响。结果表明,当Ti-mesh为阳极,阴极为SWCNTs-COOH@Ti-mesh是最佳的电极组合,在最佳实验条件(溶液pH为6.0,应用电压为2.5 V,NaNO3浓度为6 g/L),对初始浓度50 mg/L的Cu^2+去除率可达99%。