首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 187 毫秒
1.
以膨润土,羧甲基淀粉,聚乙烯醇和海藻酸钠为原料制得球形膨润土,并将其用于处理含Cr~(6+)废水.球形膨润土处理含Cr~(6+)废水的适宜条件为:投加量6 g/L,吸附时间15 min,吸附温度30℃,含Cr~(6+)废水溶液质量浓度40 mg/L,pH=6,在此条件下去除率可达98.90%.处理后的含Cr~(6+)废水质量浓度小于0.5 mg/L,达到国家规定排放标准(GB 8978-1996).处理废水后的球形膨润土经5次再生处理后,去除率仍达96.51%.  相似文献   

2.
利用香蕉皮制成吸附剂,对含有Pb~(2+)的模拟废水进行吸附.分别对吸附剂粒径、pH值、废水中Pb~(2+)初始浓度、吸附时间及吸附剂投加量条件对吸附程度进行考察.实验结果表明,香蕉皮吸附的最佳条件为:香蕉皮粒径为100目,pH=5,废水中Pb~(2+)浓度50 mg/L,吸附时间为90 min,香蕉皮投加量为0.5 g,最高吸附量为9.16 mg/g,在此条件下,100 mL水样,30℃条件下,香蕉皮对Pb~(2+)吸附率在90%以上.  相似文献   

3.
以劣质褐煤为原料制备的活性炭对含Acid black 10B的染料废水具有明显的吸附效果,研究结果表明:静态吸附时间以60 min为宜;活性炭投加量和染料初始浓度是影响吸附过程的主要因素,初始染料浓度为100 mg/L时,其投加量以1.5 g/L为宜;温度和pH值对吸附处理结果影响很小.  相似文献   

4.
蒙脱石/粉煤灰复合材料吸附含锌废水的研究   总被引:2,自引:1,他引:1  
以蒙脱石、粉煤灰为原料,添加一定量的粘结剂混合造粒制成复合颗粒吸附剂,用于处理含Zn2+废水,实验研究了吸附反应时间、吸附剂投加量、废水初始浓度及介质pH值对吸附性能的影响。研究结果表明:蒙脱石/粉煤灰复合颗粒吸附剂的最佳吸附工艺条件为:在室温下,吸附反应时间50 min,吸附剂投加量5.0 g/L,初始浓度40 mg/L,溶液pH值为5。在此条件下处理含Zn2+废水,吸附去除率为95.77%,处理后残余浓度为1.69 mg/L,达到国家一级排放标准(2.0 mg/L)。  相似文献   

5.
对改性花生壳处理含Cr6+废水进行研究,考察吸附时间、改性花生壳投加量、pH值、Cr6+溶液初始浓度对吸附效果的影响。实验结果表明,在吸附时间100min、改性花生壳投加量为5.0g/L、pH值2.0、Cr6+溶液初始浓度25mg/L、常温的优化实验条件下,硝酸改性花生壳比盐酸改性花生壳吸附效果好,硝酸改性花生壳吸附率达到87%,盐酸改性花生壳为71%。改性花生壳是一种较高效的重金属离子吸附剂。  相似文献   

6.
以两步法非均相反应合成了偕胺肟基杨絮纤维素,并用傅里叶变换红外光谱对其结构进行表征。将合成的纤维素用于吸附废水中的重金属离子,采用重铬酸钾溶液模拟含重金属离子废水,考察了吸附时间、溶液的pH以及重铬酸钾溶液初始质量浓度对改性纤维素吸附效果的影响。结果表明,改性杨絮纤维素在重铬酸钾溶液初始质量浓度为1g/L、pH为2的条件下吸附容量达到70.6 mg/g,对Cr~(6+)的吸附过程符合Langmuir吸附等温式,改性杨絮纤维素对重金属离子的吸附效果良好。  相似文献   

7.
利用粉煤灰除砷,考察碱洗和负载Fe(Ⅲ)氧化物等不同的改性方法对去除As(Ⅴ)效果的影响.结果表明,经碱洗和Fe(Ⅲ)改性的粉煤灰吸附效果(平衡吸附量Qc> 35 mg/g)明显强于未经改性的粉煤灰(平衡吸附量Qc<1 mg/g),在初始砷浓度为1 mg/L,pH值为中性的条件下,投加量为0.5 mg/L,24 h后砷...  相似文献   

8.
研究了纳米双金属铁对阻燃剂四溴双酚A(TBBPA)的降解效果,对不同负载金属、溶液pH、TBBPA初始浓度、负载量以及投加量等影响因素进行了研究。结果表明:纳米双金属铁相对于纳米铁具有更高的活性,能够更加有效地降解TBBPA,通过不同负载金属Ni、Cu以及Ag的降解TBBPA表明,nZVI/Ag降解体系效果最佳。在25?C、pH=7的条件下,1 g/L的负载率w=0.5%的nZVI/Ag对初始浓度为5 mg/L的TBBPA的降解效果最佳。nZVI/Ag降解TBBPA的反应符合假一级动力学方程。TBBPA的降解速率常数随着pH和TBBPA初始浓度的增加而降低,随着nZVI/Ag投加量以及Ag负载率的增加而升高。  相似文献   

9.
用纳米分子筛、硅藻土、纳米分子筛与硅藻土复配形成的复合材料去除废水中的非离子表面活性剂脂肪醇类聚氧乙烯醚(AEO-9),探讨了吸附时间、投加量p、H值、初始浓度几个因素对三种材料吸附AEO-9的影响,结果表明:硅藻土与纳米分子筛复配形成的复合材料去除AEO-9效果最好,吸附最佳条件为pH=6.5,AEO-9的初始浓度为400,mg/L,复合材料投加量为8,g/L,搅拌时间为25,min,去除率达到75.58%.动力学研究表明,复合材料去除AEO-9符合Langmuir等温式,说明AEO-9在复合材料表面形成单分子层的吸附层.通过XRD表征及电镜分析可知,复合材料是以硅藻土为主要骨架,同时结合了分子筛的结构,在两种复合的粒子之间形成亲和作用.  相似文献   

10.
以天然麦壳为生物吸附剂,研究其对模拟皮革废水中氨氮的吸附性能,并考察温度、氨氮的初始浓度、麦壳吸附剂的投加量、溶液的pH,以及吸附时间等因素对吸附效果的影响.实验结果表明,实验在温度为45℃、氨氮初始浓度为50mg/L、麦壳投加量为0.1g、溶液pH为8、接触时间为5h时,麦壳对氨氮的吸附去除效果最好,最大吸附量为8.144mg/g.经1mol/L的磷酸或氢氧化钠改性后,其氨氮吸附量反而下降.  相似文献   

11.
工业废水中高氯离子使其具有腐蚀性并妨碍水生动植物生长, 破坏生态环境, 在排放之前必须进行氯离子 去除, 达到排放要求。探究了单因素对氯离子去除率的影响, 并讨论了投料比、搅拌时间、静置时间以及体系初始 pH 对去除率影响及交互作用。研究表明: 搅拌速度为400 r/min, n(Al3+) : n(Ca2+) 为1 : 3.3, 搅拌时间为30 min, 静 置时间为30 min, 废水初始pH 为10 时, 去除效果最佳。应用所得最佳条件对实际水样进行二次去除实验并探讨了 相关影响因素。对实际水样二次氯离子去除实验的最佳工艺条件: 当n(Cl-):n(Al3+) : n(Ca2+) 为1 : 3.6 : 12, 初始溶 液浓度为4 g/L 时, 并且需要在二阶段投加药品前调节体系pH 值至弱碱性, 氯离子去除效率可达95%, 浓度可降到 400 mg/L 以下。通过X 射线洐射分析可知, 沉淀产物为层状结构的弗氏盐[Ca2Al(OH)6Cl·2H2O]。此方法成本低、 无污染, 对高氯废水去除有很好的应用价值。  相似文献   

12.
The pretreatment of refractory polyvinyl-alcohol (PVA) wastewater with low value of CODCr by Fenton’s reagent was investigated to enhance the biodegradability. The effects of operating conditions such as pH of the solution, Fe2+ dosage, H2O2 dosage, reaction time and initial PVA concentration on the removal efficiency of CODCr were discussed. It is demonstrated that the optimum value of pH for removal of CODCr is 5 and the most suitable dosages of H2O2 (2%) and FeSO4 (10 mg/L) are 5% and 8.0%, respectively. When the initial CODCr value of the PVA water is 760 mg/L, the favorable reaction time is 110 min. Under these optimum conditions, the removal ratio of CODCr is 58.6%–61.4%, and the value of biodegradability (CODB/CODCr) increases markedly from 8.9%–9.7% to 62.6%–68.3%.  相似文献   

13.
膨润土对废水中Cu2+的吸附性能研究   总被引:1,自引:0,他引:1  
研究了钙基膨润土和钠基膨润土对废水中铜离子的吸附特性.结果表明,钠基膨润土和钙基膨润土的吸附行为都依赖于溶液的pH值,初始离子浓度和吸附剂用量.在低pH值时主要是H+与Cu2+竞争吸附位.pH值在3到7时基本的吸附机制是离子交换的过程.在高pH值(>8.3)时,在膨润土颗粒表面形成氢氧化铜的吸附或沉淀.随初始金属离子浓...  相似文献   

14.
通过硫化对纳米零价铁 (nZVI) 进行改性, 制备了硫化纳米零价铁 (S-nZVI), 而后对三氯乙烯 (TCE) 进行降 解实验研究。利用 SEM、XRD 对 S-nZVI 进行材料的结构表征, 进而研究不同材料、不同 S/Fe 摩尔比、不同初始 TCE 浓度、不同初始 pH 条件下, S-nZVI 对 TCE 的降解效果。结果表明, S-nZVI 主要成分为 Fe0 并含有少量的 FeS, 制得的 S-nZVI 为球状结构, 表面有片层状的 FeS 生成;当 S/Fe 摩尔比为 0.6, 初始浓度为 20 mg/L 时, TCE 的降解 率为 87.2%, 远高于 nZVI (降解率为 56.4%)。经动力学分析后, S-nZVI 去除 TCE 符合伪二级动力学过程, 表明其降 解过程以化学还原为主。nZVI 经过硫化后提高了材料的电子选择性, 使其成为修复受污染土壤和地下水的有前途 的功能材料。  相似文献   

15.
利用弗罗里硅土吸附脱除石化低浓度废水中的氨氮。分别采用BET、SEM及XRF对弗罗里硅土进行表征。考察剂液比、吸附时间、pH、吸附温度及氨氮初始质量浓度等因素对吸附脱除氨氮效果的影响。结果表明,在氨氮初始质量浓度为50.00 mg/L、剂液比为2 g/L、pH为7、吸附温度为293.15 K和吸附时间为5 min的条件下,氨氮去除效果最佳;在此条件下处理石化低质量浓度氨氮废水,氨氮质量浓度从17.53 mg/L降至5.16 mg/L,去除率达到70.6%,满足GB 31570-2015的排放标准。  相似文献   

16.
研究了改性钢渣吸附除磷影响因素、等温吸附线特征和吸附动力学,并对生物处理后的出水进行吸附除磷研究。结果表明:在初始磷浓度10 mg/L,投加量10 g/L、pH为7时,改性钢渣吸附后总磷浓度为0.687 mg/L,去除率达93%;改性钢渣对磷的吸附符合Langmuir模型,理论饱和吸附量是1.977 mg/g,吸附动力学符合准二级动力学模型(R2>0.99);实际生活污水的吸附除磷中,投加量为50 g/L,反应2 h后出水总磷浓度达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)一级B标的排放要求。  相似文献   

17.
Coal fly ash is a typical secondary aluminum/silicon resource. The preparation of zeolite-type absorbent is a potential way for its value-added utilization, while the purity and adsorption property of zeolite are limited due to the occurrence of side reactions in the synthesis process. In this study, a designated composite consisted of crystalline zeolites and amorphous calcium silicate hydrate was selected, which was direct synthesized from fly ash under conditions of a Ca/Si molar ratio of 0.8, an initial NaOH concentration of 0.5 mol/L, a hydrothermal temperature of 170 ℃ and a liquid–solid ratio of 15 mL/g. The results indicated that this composite had superior adsorption property for a variety of heavy metals, which was based on the exchange of calcium and sodium ions in zeolites and calcium silicate hydrate. Its adsorption capacities for Pb2+, Ni2+, Cd2+, Zn2+, Cu2+ and Cr3+ attained 409.4, 222.4, 147.5, 93.2, 101.1 and 157.0 mg/g, respectively, in single solution with a pH of 4.5. After regulating the synthesis conditions, the transformation of amorphous calcium silicate hydrate into crystallized tobermorite weakened the adsorption capacity of the composite. Besides, due to the competitive adsorption in a multiple ions solution, the adsorption capacities for these heavy metals had a reduction.  相似文献   

18.
Sugarcane pulp residue (SPR), a waste from sugar-refinery, which possesses a large surface area, can be used for removing chromium (Cr(III) and Cr(VI)) from wastewater. In this work, the kinetics, isotherms of Cr(III) and Cr(VI) adsorption and their removal by SPR were investigated. The results show that the removal percentages of Cr(VI) and Cr(III) increase with increasing SPR dosage and temperature and decrease with increasing SPR particle size and the initial concentration of chromium ions. However, the influence of pH value on the Cr(VI) removal differs from that of the Cr(III) removal. The Cr(VI) removal percentage decreases with increasing pH values, while the Cr(III) removal percentage increases with increasing pH value. The adsorption kinetics of Cr(VI) and Cr(III) well fits with pseudo-second-order model. Langmuir adsorption isotherm can well describe the adsorption phenomena of chromium ions with the maximum adsorption capacity of 0.567 mg/g for Cr(VI) and 3.446 mg/g for Cr(III). Moreover, SPR reveals higher adsorption capacity for Cr(III) than that for Cr(VI), which implies that SPR has more potential application for Cr(III)-containing wastewater treatment than that for Cr(VI)-containing wastewater treatment. Foundation item: Projects(2006AA06Z374, 2007AA021304) supported by the National High-Tech Research and Development Program of China; Project(2008SK2007) supported by the Key Program of Science and Technology of Hunan Province, China  相似文献   

19.
Forming adsorbents FFA-R, FFA-A and FFA-B were prepared from different particle size coal fly ashes FA-R, FA-A and FA-B, their average particle sizes (d 50) were 15.75, 3.61 and 1.73 μm respectively. The structure and adsorption properties for Cr6+ of forming adsorbents from aqueous solution were studied. The results show that forming adsorbent prepared from the coal fly ash with smaller particle size exhibits higher specific surface area, higher pore volume and better adsorption properties for Cr6+.The adsorption kinetics of Cr6+ on FFA-R, FFA-A and FFA-B fitts the second order kinetic model and the second adsorption rate constants are 7.523, 3.197 and 2.187 mg·g-1· min-1/2, respectively. The adsorption of Cr6+ on FFA-R, FFA-A and FFA-B can be described in terms of Langmuir isotherms better, and the adsorption processes are spontaneous and exothermic.  相似文献   

20.
A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating resin for Pb2+ were studied by batch adsorption, and the adsorption process was analyzed from thermodynamics and kinetics aspects. The adsorption mechanism of Pb2+ on the modified D401 chelating resin was discussed by FT-IR spectrometry. Experimental results show that in the Pb2+ concentration range of 200–400 mg/L, the adsorption capacities of the modified D401 chelating resin for Pb2+ increase by 77%–129%, and Langmuir isothermal adsorption model is more suitable for the equilibrium adsorption data. Adsorption is an endothermic process that runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best pH value under adsorption condition is 4–5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the adsorption capacity remains stable after five consecutive adsorption-desorption cycles. The maximal static saturated adsorption capacity of the resin is 206 mg/g at 333 K in the Pb2+ concentration range of 200–400 mg/L. The modified D401 chelating resin is an efficient adsorbent for the removal of Pb2+ from its single-metal ion solution. Foundation item: Project(708049) supported by the Important Item Cultivation Foundation of Scientific Innovation Project of Colleges and Universities of China  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号