结构态亚铁羟基化合物还原预处理印染废水的效果和机制

印染废水的脱色是重要的处理难题。以6种偶氮染料模拟废水和实际印染废水为目标污染物,研究了亚铁羟基化合物(ferrous hydroxy complex ,FHC)还原预处理印染废水的效果和机理。通过亚铁结构形态、初始pH、FHC投加量、Fe/OH^-摩尔比等因素对FHC还原转化染料的影响研究,综合评价了FHC对多种偶氮染料的反应性能。实验结果表明FHC具有较高的还原活性,投加89.6 mg·L^-1的FHC,可以去除90%以上的偶氮染料。亚铁结构形态对还原脱色有很大影响,溶解态亚铁基本不能还原偶氮染料,结构态亚铁FHC相似文献   

2种新型重金属絮凝剂复配处理含铜废水

采用2种新型重金属絮凝剂巯基乙酰化胺甲基聚丙烯酰胺(MAAPAM)和聚乙烯亚胺基黄原酸钠(PEX)处理含铜废水,分别考察了其单独和复配处理对废水中Cu2+的去除效果。结果表明,PEX和MAAPAM对不同Cu2+浓度的废水均具有良好的去除性能,且PEX对Cu2+的去除效果优于MAAPAM。当采用PEX和MAAPAM复配处理含Cu2+废水(Cu2+质量浓度为100 mg/L,pH为6.0)时,先投加340 mg/L的MAAPAM进行絮凝试验,在快搅2 min时投加10 mg/L的PEX继续搅拌,出水中Cu2+的剩余浓度可以满足排放标准要求,且具有较低的处理成本。     

碱改性脱水污泥生物吸附剂处理镍冶炼酸性废水工艺研究

以脱水污泥为原料通过碱改性制备得到生物吸附剂,采用该生物吸附剂对镍冶炼烟气制酸废水中重金属离子进行吸附去除。考察了吸附时间、pH、生物吸附剂的投加量以及混凝药剂的投加等条件对酸性废水中Ni、Pb、Cd、Cu等金属离子去除效果的影响。结果表明,生物吸附剂适宜操作条件为吸附时间为120 min,pH为5~7,吸附剂投加量为7 mL/100 mL(吸附剂体积/废水体积)。处理后废水中重金属离子含量能达到GB 25467-2010的排放要求。絮凝剂的投加对于吸附剂去除废水中重金属离子的协同作用并不明显。     

重金属捕集剂去除冷轧酸洗废水中铬镍的应用研究

基于传统石灰法处理冷轧酸洗废水,对比研究了重金属捕集剂投加位置、重金属捕集剂联合"石灰+铁盐"深度处理工艺、重金属捕集剂联合高密度污泥深度处理工艺对冷轧酸洗废水中总铬和总镍去除效果的影响。实验结果表明:重金属捕集剂联合高密度污泥处理澄清池出水,当重金属捕集剂、高密度污泥投加质量浓度分别为40、2 500 mg/L时,处理出水满足《钢铁工业水污染物排放标准》(GB 13456—2012)水污染物特别排放限值的要求。     

接枝羧基淀粉去除电镀废水中的铜、锌离子

利用水不溶性接枝羧基淀粉(简称ISC)去除废水中Cu2+和Zn2+。研究结果表明,对于铜溶液初始质量浓度为14 mg/L,ISC投加量为1.4 g/L,pH值为10,反应时间为20 min时,去除铜离子的效果为最佳;对于锌溶液初始质量浓度为10 mg/L,ISC投加量为1.7 g/L,pH值为10,反应时间为20 min时,去除锌离子的效果为最佳。用ISC处理实际电镀废水,能达到国家排放标准。     

弱磁场强化零价铁去除废水中重金属离子试验研究

考察了弱磁场对零价铁去除铜冶炼废水中重金属离子的加速作用。结果表明,当稀贵车间废水初始p H为4.0~5.0,微米铁粉投加量为0.1~0.5 g/L时,预磁化和加磁均能加速零价铁对稀贵车间废水重金属离子的去除。在初始p H为4.0,微米铁粉投加量为1.0 g/L的条件下,对水淬车间高砷废水进行处理,结果发现,外加磁场对微米铁去除高砷废水中总砷仍有很强的促进作用。     

电镀废水中重金属离子的去除研究

对某电镀厂的电镀废水采用破氰、亚硫酸钠还原和聚丙烯酰胺絮凝沉淀的方法去除其中的Cr6+和Cu2+。结果表明,最佳破氰条件为:p H=10,破氰率可达96.4%,废水中的CN-浓度降为0.122 mg/L;Cr6+的最佳还原条件为:p H=2,亚硫酸钠投加量为300 mg/L,还原率可达91.4%;Cr6+的最佳沉淀条件为:p H=2,聚丙烯酰胺的投加量为3g/L,去除率可达87.0%,废水中的Cr6+浓度降为0.195 mg/L;Cu2+的最佳沉淀条件为:p H=9,聚丙烯酰胺的投加量为2 g/L,去除率可达79.6%,废水中的Cu2+浓度降为0.318 mg/L。经过处理后,CN-,Cr6+和Cu2+的出水浓度均达到行业排放标准。     

钛纳米管净化渔业养殖水中重金属的实验研究

通过实验研究了钛纳米管材料对渔业养殖水中Cu、Pb、Cd、Cr等重金属的去除效果,并通过BET、TEM等手段对材料进行了表征,验证了钛纳米管用于净化养殖废水中重金属的可行性。结果表明:钛纳米管对养殖水中重金属Cu、Pb、Cd去除效果较好,在投加量为5 g/L时,反应2小时后即完全去除;增加反应时间和材料投加量,测试的大部分重金属去除率会升高;钛纳米管对初始浓度较高的养殖水中Cd、Cr去除效果明显好于初始浓度较低的养殖水;钛纳米管微观成像呈现典型的纳米管状结构,其比表面积及孔容较大,有利于吸附速率提升。     

高分子螯合剂乙硫氮处理铜冶炼工业废水的研究

研究了高分子螯合剂乙硫氮处理铜冶炼工业废水的工艺条件。实验结果表明:在常温下,将铜冶炼工业废水的pH调至6~7,质量分数为10%的乙硫氮溶液用量为2 mL,快速搅拌(300 r/min)1 min,慢速搅拌(100 r/min)10 min,处理后的废水中Cu2+、Pb2+、Zn2+、Cd2+、Ni2+等重金属离子的残留浓度均为微量,低于国家污水综合排放标准(GB 8978—1996)允许值或一级标准。     

铁氧体法处理电镀废水实验研究

采用铁氧体法处理未达标的电镀废水,研究在不同的操作条件下,铁氧体法去除电镀废水中各重金属离子的效果;研究结果表明:当FeSO4投加量12,废水pH为10,停留时间为45min时,总Cr、Cu2+、Ni2+平均去除率基本稳定在92%、88%、85%,处理后废水中总Cr、Cu2+、Ni2+平均浓度分别为0.075、0.30、0.035mg/L,达到国家一级排放标准;处理成本仅为0.25元/t,是一项技术可行、经济合理的电镀废水处理技术。     

生物质固定化硫酸盐还原菌处理废水中重金属离子

采用海藻酸钠和3种生物质载体(稻壳、玉米芯、秸秆)固定化的硫酸盐还原菌(SRB)处理单一重金属(700 mg/L Fe2+, 75 mg/L Cu2+, 120 mg/L Pb2+, 80 mg/L Cd2+)废水,筛选出稻壳为效果较优的固定化载体,并对合成重金属废水(含400 mg/L Fe2+, 30 mg/L Cu2+, 50 mg/L Pb2+, 40 mg/L Cd2+)的处理效果作了进一步研究. 结果表明,稻壳固定化SRB去除单一重金属时,Fe2+, Cu2+, Pb2+, Cd2+去除率分别为99%, 100%, 100%, 100%;处理合成重金属废水时,4种重金属去除率分别为98.06%, 100%, 99.35%, 100%.     

螯合沉淀法处理燃煤电厂脱硫废水

采用螯合沉淀法,选用重金属离子捕集沉淀剂DTCR,对某燃煤电厂的烟气脱硫废水进行了重金属处理,结果表明,出水总Hg为0.004mg/L,总Cd为0.003mg/L,总Pb为0.013 mg/L,总Ni为0.02 mg/L,总Cu为0.012mg/L,总Zn为0.034 mg/L,达到《污水综合排放标准》(GB8979-1996)要求。     

纤维素黄原酸盐处理重金属废水的条件优化研究

采用纤维素黄原酸盐处理重金属废水,对纤维素黄原酸盐的用量、pH值、反应时间等条件进行了研究。结果发现:1L含氰电镀废水(含Cr3+15mg/L、Cu2+3mg/L、Ni2+9.2mg/L、Zn2+6mg/L),加入2g纤维素黄原酸盐,调节pH8,搅拌1h,过滤,处理后的废水中Cr3+、Cu2+、Zn2+、Ni2+残余浓度分别为0.08mg/L、0.03mg/L、0.12mg/L、0.10mg/L。含有重金属盐的残渣,可用硫酸或硝酸处理,以回收重金属。     

Insights into the Adsorption of Heavy Metals from Wastewater using Diatomaceous Earth

The release of large quantities of heavy metals (e.g., Zn, Cu, Pb, Ni, Cd, etc.) into the natural environment has resulted in a significant number of environmental problems, disorderliness in human physiology, and other biological systems due to their high toxicity to plant, animal, and human life. This review paper explores the feasibility of diatomaceous earth for the adsorption of heavy metals from wastewater, its application in metal adsorption, and wastewater purification. Impregnating the diatomite surface with 0.38 g/g of manganese oxide gave a 2.4-fold increase in the adsorbent surface area. A number of equilibrium studies demonstrated that treated diatomite has a higher removal capacity for heavy metals from water than untreated diatomite. The future challenges and prospect of diatomite were also addressed. Conclusively, it was established that the use of diatomaceous earth is a promising technology in the removal of heavy metals from wastewaters and environment     

Rapid Adsorption of Heavy Metals by Fe3O4/Talc Nanocomposite and Optimization Study Using Response Surface Methodology

Fe₃O₄/talc nanocomposite was used for removal of Cu(II), Ni(II), and Pb(II) ions from aqueous solutions. Experiments were designed by response surface methodology (RSM) and a quadratic model was used to predict the variables. The adsorption parameters such as adsorbent dosage, removal time, and initial ion concentration were used as the independent variables and their effects on heavy metal ion removal were investigated. Analysis of variance was incorporated to judge the adequacy of the models. Optimal conditions with initial heavy metal ion concentration of 100, 92 and 270 mg/L, 120 s of removal time and 0.12 g of adsorbent amount resulted in 72.15%, 50.23%, and 91.35% removal efficiency for Cu(II), Ni(II), and Pb(II), respectively. The predictions of the model were in good agreement with experimental results and the Fe₃O₄/talc nanocomposite was successfully used to remove heavy metals from aqueous solutions.     

柠檬酸和谷氨酸N，N-二乙酸优化处理污泥重金属

采用柠檬酸（CA）和谷氨酸N,N-二乙酸（GLDA）处理污泥重金属,研究了试剂浓度、pH和反应时间对重金属去除效果的影响,并以重金属去除率为表征,通过正交试验获得CA和GLDA处理重金属的最佳条件。结果表明,增加试剂用量、降低体系pH均有利于重金属的去除,但延长反应时间对重金属的去除效果影响不明显。CA和GLDA处理污泥重金属的最佳条件分别为：CA 0.3 mol·L^-1、pH 4、反应时间2 h和GLDA 0.05 mol·L^-1、pH 4、反应时间3 h。最佳反应条件下,对于CA和GLDA,重金属Cd、Cu、Pb和Ni的去除率可分别达80.25%、77.75%、64.66%和75.16%,及78.57%、78.48%、64.84%和76.71%。CA和GLDA对重金属的去除效果大小顺序均为：Cd>Cu> Ni>Pb,但GLDA的处理效果优于CA。污泥经CA和GLDA处理后,污泥固相酸溶态重金属含量下降幅度最大,平均达81%,残渣态重金属含量下降52.1%,而污泥液相中重金属含量则增加了17.54倍,说明重金属从污泥固相向液相转移。SEM镜检发现,污泥由处理前表面分散的絮状结构,变成更为明显的团块结构和片层结构,污泥的吸附能力下降,且体积缩小。研究结果表明,CA和GLDA处理污泥能有效降低污泥重金属含量并提高污泥固相重金属的化学稳定性,有利于污泥脱水及脱水后的进一步处理及其资源化。     

改性泥炭对Pb~(2+)、Ni~(2+)、Cu~(2+)的吸附性能研究

在静态条件下,研究了改性泥炭对重金属离子Pb2+、Ni2+、Cu2+的吸附性能,着重探讨了改性泥炭去除废水中重金属离子Pb2+、Ni2+、Cu2+的适宜条件,同时对改性泥炭的吸附及解吸再生机理进行了初步分析。结果表明:在25℃条件下,当pH值为5～7、吸附剂用量为2g/L、吸附时间为2h时,改性泥炭对Pb2+、Ni2+、Cu2+的去除率分别为98.0%、96.7%、95.5%。吸附了重金属离子的改性泥炭经酸解吸再生后,可循环使用,不会带来二次污染。     

生化—氧化—人工湿地立体处理工艺中试研究

针对高盐有机废水一定有机物、盐度高、可生化性差等特点,采用生化-氧化-人工湿地立体处理工艺处理,中试论证工艺可行性。结果表明,进水COD能从890~2900 mg/L降至30 mg/L以下;控制进水NH4^+-N的质量浓度在300 mg/L以内,出水NH4^+-N的质量浓度在1.5 mg/L以下;进水TP的质量浓度在53~350 mg/L以内,出水TP的质量浓度可去除低于0.3 mg/L;对Cu、Ni等重金属去除效果好,Cu、Ni均可去除至达标排放。出水主要指标达到严于GB 3838-2002的地表水IV类水质标准,废水处理运行总成本约为71.31元/t。该工艺将3个处理单元分别放置在一个立体建筑物不同层次,具有处理成本低、处理效果好、节约用地等优势。     

Adsorption of Cu(II) ions from aqueous solutions using ion exchange resins with different functional groups

The extraction of heavy metals from industrial effluents using efficient adsorbents is crucial for wastewater treatment and beneficial for metal recycling. In this study, the removal of Cu(II) from an acidic solution by commercial resins Dowex G-26 and Puromet™ MTS9570 was investigated. The influences of contact time, solution concentration, pH, temperature, and a resin dosage on the adsorption process were studied with batch technique. The optimum adsorption conditions were obtained at a concentration of 1100 mg/L Cu, contact time of 30 min, pH 3.5, and resin dosage of 0.025 g/ml for the removal of 99.9% and 90% of copper ions by G-26 and MTS9570, respectively. The experimental data of copper adsorption were analyzed using the Langmuir, Freundlich, and Temkin isotherm models. The highest metal uptakes of 41.67 and 37.70 mg/g were observed for Dowex G-26 and MTS9570, respectively. It was found that both resins had higher adsorption capacities than the substances reported in the literature. The adsorption kinetic studies showed that the copper adsorption process could be better described by the pseudo-second order model. Adsorption occurs spontaneously under endothermic conditions, which indicates the endothermic nature of the process.     

Implementation of Hybrid Inorganic/Organic Adsorbents for Removal and Preconcentration of Heavy Metals from Industrial Waste and Drinking Waters

Three hybrid inorganic/organic adsorbents based on alumina and phenylazoformic acid 2-phenylhydrazide were synthesized, characterized and examined for their heavy metal sorption properties. The main purpose of this research paper is to study and explore the combined hybrid characters of inorganic/organic sorbents for the selective removal and preconcentration of heavy metals via static and dynamic solid phase techniques from industrial wastewater and drinking tap water samples as well. The hybrid inorganic/organic adsorbents were identified as strongly resistive to leaching in solutions with pH 1–7 and thermally stable up to 350°C. Optimization of heavy metal removal by implementation of newly designed hybrid inorganic/organic adsorbents was studied in presence of various factors as the effect of pH of contact solution and reaction time via determination of the metal sorption capacity and distribution coefficient. The hybrid adsorbents were successfully implemented for the selective removal of Pb(II), Cu(II), Fe(III), and Cr(III) from industrial wastewater samples with recovery values in the range of 91–99 ± 2–3% as well as 98–99 ± 1–3% for the selective preconcentration of Pb(II), Cu(II), and Cr(III) from drinking tap water samples without noticeable interference caused by the matrix effect.