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1.
张林  冯江涛  王宁  徐浩  延卫 《环境化学》2018,37(12):2621-2629
本文以钛酸异丙酯为钛源,以甘氨酸(gly)为改性材料,通过水解法在比较温和的条件下合成了二氧化钛(TiO2-gly)吸附剂,同时以亚甲基蓝(MB)和酸性红G(ARG)两种染料为处理对象,考察了合成的TiO2的吸附性能,并将之与P25材料进行对比.结果表明,经过甘氨酸改性的TiO2吸附剂的比表面积大幅提升到354.2 m2·g-1;改性TiO2对亚甲基蓝(100 mg·L-1)和酸性红G(100 mg·L-1)两种染料的吸附能力得到较大提高,最大吸附量分别为49.25 mg·g-1和43.98 mg·g-1,远高于P25对二者的吸附容量(分别为28.24 mg·g-1和16.40 mg·g-1);P25的吸附主要受物理吸附作用控制,而改性TiO2吸附剂20 min即可达到吸附平衡,并展现出准二级动力学和Langmuir吸附等温线特性,这表明吸附剂与染料分子之间主要为化学吸附.另外,通过吸附影响因素实验发现通过延长吸附时间、控制pH都能提高该吸附剂的吸附性能,而改性TiO2-gly吸附剂经过5次再生循环实验后仍展现出较好的吸附性能.  相似文献   

2.
黄河沉积物对磷的吸附行为   总被引:2,自引:0,他引:2  
研究了黄河流域9个沉积物对磷的吸附行为,用修改后的Langmuir等温吸附模型对吸附实验数据进行了拟合,得到最大吸附容量PAC、Langmuir吸附平衡常数k.利用所得拟合参数通过公式计算方法得到EPC_0,以此判断沉积物是磷"源"还是磷"汇",分析了沉积物组成及其理化性质与磷吸附特征的关系.结果表明,各沉积物的吸附,解吸平衡磷浓度EPC_0范围在0.0031~0.109 3 mg/L,,其值也较低,与可解吸的内源磷含量正相关,与地理位置没有表现出相关性.在本研究条件下,在壶口张家湾断面,沉积物对磷表现为"汇";而其他沉积物对磷表现为"源",但释放量和吸附量不大.黄河沉积物对磷的最大吸附容量PAC的范围为0.073~0.454 mg/L,吸附能力较弱,沉积物的最大吸附容量与沉积物的有机质有较好的正相关关系.此外,沉积物对磷的吸附存在明显的固体浓度C_S效应,吸附滞后角随着C_S的增加而增大,随着同体浓度的增加,沉积物对P的吸附量逐渐降低,但EPCC_0值却增大,体现了颗粒物在磷循环中的两性作用.  相似文献   

3.
李北罡  马钦  刘培怡 《生态环境》2010,19(8):1901-1905
研究了黄河中下游10个不同表层沉积物在黄河水体中对磷酸盐(P)的吸附动力学及其影响因素和吸附机理。结果表明:(1)不同黄河沉积物对P的吸附能力各不相同,但吸附量随时间的变化具有相同的变化趋势,吸附速率均在前8h内较快,以后逐渐趋缓,在48h时基本达到吸附平衡。不同黄河沉积物对P的吸附量均随P初始质量浓度的增加而增大,随沉积物含量增大而减小;(2)不同沉积物在不同P初始质量浓度下对P的吸附动力学均符合Lagergren二级吸附动力学模型及Weber-Morris扩散方程,求得二级吸附速率常数和扩散速率常数分别在11.9866~157.55g·mg^-1·h^-1和0.0005~0.0119mg·g^-1·h^-1/2之间,吸附过程由P在沉积物内扩散控制。  相似文献   

4.
黄河上游沉积物对磷酸盐的吸附动力学研究   总被引:1,自引:0,他引:1  
李北罡  刘培怡  马钦 《生态环境》2010,19(11):2693-2697
研究了黄河上游10个不同表层沉积物在黄河水体中对磷酸盐(P)的吸附动力学及其影响因素和吸附机理。结果表明:不同黄河沉积物对P的吸附能力各不相同,但吸附量随时间的变化具有相同的趋势,吸附速率均在前8 h内较快,以后逐渐趋缓,在48 h时基本达到吸附平衡。不同黄河沉积物对P的吸附量均随P初始质量浓度的增加而增大,随沉积物质量浓度增大而减小,且也受水体pH值的影响,在pH为6.0~9.0范围内吸附量比较大。不同沉积物在不同P起始质量浓度下对P的吸附动力学均符合Lagergren二级吸附动力学模型及Weber–Morris扩散方程,求得二级吸附速率常数和扩散速率常数分别在10.85~229.29 g.mg-1.h-1和0.7×10-3~5.2×10-3 mg.g-1?h-1/2)之间,吸附过程由P在沉积物内的扩散控制。  相似文献   

5.
    
In this work, continuous removal of Malachite Green from aqueous solution by adsorption was investigated using a laboratory scale fixed-bed column packed with binary solid mixture of seashell powder (SSP) and eggshell powder (ESP). The effects of initial dye concentration, feed flow rate, bed height, and the SSP?:?ESP ratio in the binary solid mixture on the breakthrough characteristics were studied. The breakthrough time decreased with increase in the flow rate and the initial dye concentration. The breakthrough time also varied greatly with change in bed height. The breakthrough time increased from 17.2?h to 34.5?h with increase in bed height from 6?cm to 12?cm. The breakthrough time was significantly affected by the change in the SSP?:?ESP ratio in the binary mixture. The breakthrough time decreased with increase in the SSP ratio in the binary mixture. In order to determine the column kinetic parameters, three different column kinetic models, namely Adams–Bohart, Bed Depth Service Time (BDST), and Yoon–Nelson models were fitted to the dynamic flow experimental data. The BDST model showed good agreement with the experimental results at all the process parameters studied. Results suggest that this novel approach of simultaneous utilization of adsorbents can be adopted for the treatment of dye-bearing effluents.  相似文献   

6.
利用好氧颗粒污泥对酸性淡黄2G溶液进行吸附脱色研究,考察了pH值、吸附剂用量、初始酸性淡黄2G的浓度、温度以及NaCl浓度对吸附过程的影响.实验结果表明,吸附过程对溶液pH值具有很高的依赖性,其最佳pH值为2.0.Temkin等温线在整个实验染料浓度范围内能够很好地描述吸附过程.吸附动力学符合准二级动力学模型.内部扩散和边界层扩散都可能影响生物吸附速率.热力学分析表明,吸附过程是一个自发的放热过程.采用FTIR分析的结果进一步揭示了颗粒污泥上官能团(如胺基、羧基和羟基等)可能是染料生物吸附的活跃结合位点.这些结果表明,好氧颗粒污泥可以作为吸附剂以去除水中的酸性淡黄2G.  相似文献   

7.
黄河水体沉积物对敌百虫和甲拌磷的吸附   总被引:8,自引:0,他引:8       下载免费PDF全文
李桂芝  刘永明 《环境化学》2001,20(3):244-248
对敌百虫和甲拌磷在黄河水体沉积物中的吸附特性进行了研究,观察了pH值和离子强度等因素对吸附的影响。结果表明,敌百虫的吸附过程为一级动力学规律;敌百虫的吸附符合Langmuir等温式,甲拌磷的吸附可用Freundich等温式较好地描述。pH值降低或离子强度增加使敌百虫和甲拌磷在沉积物中的吸附程度明显减小。敌百虫在黄河水体沉积物中的吸附以表面吸附为主,而甲拌磷则表现为表面吸附和在有机碳中的分配作用两种吸附方式。  相似文献   

8.
    
The adsorption potential of FMBO, FeOOH, MnO2 for the removal of Cd2+, Cu2+ and Pb2+ in aqueous systems was investigated in this study. Comparing to FMBO and FeOOH, MnO2 offered a much higher removal capacity towards the three metal ions. The maximal adsorption capacity of MnO2 for Cd2+, Cu2+ and Pb2+ were 1.23, 2.25 and 2.60 mmol·g-1, respectively. And that for FMBO were 0.37, 1.13, and 1.18 mmol·g-1 and for FeOOH were 0.11, 0.86 and 0.48 mmol·g-1, respectively. The adsorption behaviors of the three metal ions on the three adsorbents were all significantly affected by pH values and heavy metal removal efficiency increased with pH increased. The Langmuir and Freundlich adsorption models were used to describe the adsorption equilibrium of the three metal ions onto the three adsorbents. Results showed that the adsorption equilibrium data fitted well to Langmuir isotherm and this indicated that adsorption of metal ions occurred on the three metal oxides adsorbents limited to the formation of a monolayer. More negative charged of MnO2 surface than that of FMBO and FeOOH could be ascribed by lower pHiep of MnO2 than that of FMBO and FeOOH and this could contribute to more binding sites on MnO2 surface than that of FMBO and FeOOH. The higher metal ions uptake by MnO2 than FMBO and FeOOH could be well explained by the surface charge mechanism.  相似文献   

9.
    
Dyes are common pollutants in textile wastewaters, and the treatment of the wastewater has now attracted much attention due to its wide application and low biodegradability. In this study, Fe0/C/Clay ceramics, a kind of novel micro-electrolysis filler, were sintered and employed in a dynamic micro-electrolysis reactor for synthetic Acid Red 73 (AR73) and Reactive Blue 4 (RB4) wastewater treatment. The effects of influent pH, hydraulic retention time (HRT), and aeration on the decoloration efficiencies of AR73 and RB4 were studied. The optimum conditions for wastewater treatment were: AR73, influent pH of 4, HRT of 2 h and aeration; RB4, influent pH of 5, HRT of 6 h and aeration. Under the optimum conditions, decoloration efficiency of AR73 and RB4 wastewater was 96% and 83%, respectively. Results of UV-vis spectrum scanning demonstrated that the chromophores were broken. Continuous running tests showed that improvement of micro-electrolysis system with Fe0/C/Clay ceramics for AR73 and RB4 synthetic wastewater treatment could avoid failure of micro-electrolysis reactor, which indicated great potential for the practical application of the ceramics in the field of actual industrial wastewater treatment.  相似文献   

10.
层状氢氧化镁铝对染料酸性橙Ⅱ的脱色性能   总被引:2,自引:0,他引:2       下载免费PDF全文
赵毅  牛向楠  王山  朱洪涛 《环境化学》2011,30(5):1019-1024
分别用层状氢氧化镁铝(LDHs)和焙烧层状氢氧化镁铝(CLDH)作为吸附剂,吸附脱除水溶液中染料酸性橙Ⅱ,考察了Mg/Al物质的量之比、吸附剂的投加量、脱色时间、初始pH值等因素对脱色率的影响.结果表明,以Mg/Al物质的量之比为3制得的层状氢氧化镁铝对酸性橙Ⅱ溶液的脱色效果最好;室温下,3.0 g·L-1LDHs和1.0 g·L-1的CLDH对浓度为70 mg·L-1的染料的脱色率分别达96.97%和99.88%;焙烧态的层状氢氧化镁铝在脱色时用量更少、脱色反应更迅速、适用的pH范围更广、脱色性能更好;饱和吸附后的LDHs用高温热解法再生,吸附性能良好,随再生次数增多,脱色率下降.  相似文献   

11.
本文合成了β-环糊精功能化的石墨烯纳米材料(β-CD-GNs),考察了其作为一种新型高效吸附剂对水中酸性大红G(ASG)和橙黄Ⅱ(Orange Ⅱ)的吸附性能.该材料结合了石墨烯和β-环糊精的特性,表现出对所述两种染料良好的吸附性能,吸附平衡时间小于3 min,吸附率达90%以上,β-CD-GNs对ASG和橙黄Ⅱ的最大吸附量为622.2 mg·g-1和534.7 mg·g-1.另外,考察了β-CD-GNs用量、溶液pH、反应温度对吸附效果的影响. 结果表明,当溶液pH值为6.0,β-CD-GNs浓度达到25 mg·L-1时,吸附率最大,而且吸附率随反应温度升高而降低.通过对吸附数据进行线性拟合发现,β-CD-GNs对ASG和橙黄Ⅱ的吸附等温线符合Langmuir吸附等温式.该材料在印染废水的处理领域有潜在的应用价值.  相似文献   

12.
二叉树创建算法的研究   总被引:2,自引:0,他引:2  
通过对二叉树四种遍历方法的分析,给出四种建立二叉树的通用算法,以及对这些算法效率的初步分析.解决了二叉树在实际应用中创建的问题,同时,给出的算法对一些高级树型数据结构的研究也具有一定参考价值.参4.  相似文献   

13.
The photodegradation of Acid blue 74 in aqueous solution employing a H2O2/ultraviolet system in a photochemical reactor was investigated. The kinetics of decolorization were studied by application of a kinetic model. The results show that the reaction of decolorization followed pseudo-first order kinetics. We demonstrate that there is an optimum H2O2 concentration, at which the rate of the decolorization reaction is maximum. Irradiation at 253.7 nm of the dye solution in the presence of H2O2 results in complete discoloration after ten minutes of treatment.  相似文献   

14.
陈友媛  刘花  杨世迎  赫刚 《环境化学》2013,32(10):1970-1975
2012年4月23—26日黄河向东昌湖补水期间,从入湖口到出湖口布设5个纵断面监测点,同步观测流速、悬浮泥沙含量、化学需氧量(COD)变化情况,并对比分析整个湖区12个监测点补水前后的COD值.结果表明,黄河补水阶段对东昌湖水体流速、泥沙含量及COD的影响主要集中在入湖口附近,范围有限;悬浮泥沙含量与COD相关系数在补水阶段达0.843,补水前后不相关;虽然黄河水中COD含量比湖区高,在补水阶段总入湖口处COD峰值达65 mg·L-1,到出湖口处COD平均值下降为15.68 mg·L-1.同样,补水后整个湖区原水样COD平均含量比补水前下降了21%,悬浮态COD平均含量下降了10%.原水样COD和清水样COD浓度在补水阶段入湖口处峰值差达45 mg·L-1,这意味着黄河泥沙对COD有极强的吸附力,一方面吸附自身携带COD,另一方面从湖泊水体中吸附COD.分析黄河水悬浮泥沙中的各种有机成分表明,不易被酸碱所溶解的胡敏素物质占63.1%,说明黄河泥沙携带COD对湖水不易造成污染,而且悬浮泥沙可将吸附的有机污染物迁移至底泥,起到自然净化的作用.  相似文献   

15.
NKA—Ⅱ大孔吸附树脂吸附高浓度苯胺溶液的试验研究   总被引:4,自引:0,他引:4  
占新民  王建龙 《环境化学》1999,18(4):359-365
本文利用NKA-Ⅱ大孔吸附树脂对高浓度苯胺溶液进行了静态吸附试验,希望利用大孔吸附树脂从化工废水中回收苯胺。  相似文献   

16.
改性泥炭对水溶液中铬的去除   总被引:11,自引:0,他引:11  
为克服泥炭利用过程中存在的一些问题,对原泥炭进行了改性处理,并将改性后的泥炭与树脂结合以增强改性泥炭的机械强度。通过静态试验方法研究了改性泥炭对来自水溶液中的铬离子的吸附特性。结果表明:改性泥炭对水溶液中的铬的吸附等温过程符合Freundlich吸附等温方程,其吸附动力学符合准二级动力学方程。溶液的pH值对铬的去除产生显著的影响,在pH在1.5-3.0时,改性泥炭对6价铬的去除效果最好。  相似文献   

17.
本文对丙烯腈-甲基丙烯酸甲酯二元共聚物(PAN)超滤膜的成膜过程及膜分离性能进行了研究。结果表明:由PAN-双溶剂-酯类铸膜液制成的超滤膜对牛血清蛋白的截留率(R)为97.62%,通量(f)为84.96ml/cm~2.h.通过电子显微镜扫描观察膜底、表层以及膜断面的结构,对膜的形成机理与膜分离性能进行了研究,证明PAN是一种性能良好的新型膜材料,用PAN二元共聚物超滤膜对α-粉酶进行超滤浓缩试验,取得了较好的结果。  相似文献   

18.
Sorghastrum Nutans L. Nash is used as an adsorbent for the removal of Cr(VI) from wastewater. Adsorption coupled reduction i.e. indirect reduction is the mechanism of Cr(VI) removal by the biomaterial. The adsorbent surface became highly positively charged at lower pH, adsorption rate of Cr(VI) is faster and reduction reaction also accelerates at lower pH since the binding of negatively charged Cr(VI) ion species to the cationic groups is enhanced and protons take part in this reaction. The adsorbent is characterised by using XRD, FTIR, SEM and EDAX analysis. OH bending, CN stretching/bending and NH stretching play a major role in Chromium adsorption. Experimental values follow pseudo-second order reaction and Langmuir adsorption isotherm. Surface diffusion is the rate controlling mechanism for the process. The maximum percentage of Cr(VI) removal obtained is 75.5% with 7?g/L dosage at pH 1.3 and adsorbate concentration was 100?mg/L. From the normal probability, residual, contour, 3D surface, main effect and interaction plot along with t-test, ANOVA, and F-test, it is observed that pH has the most significant effect on the percentage removal followed by adsorbent dosage and time. The adsorbate concentration has the least effects and interaction effects are found to be significant.  相似文献   

19.
青霉菌对活性艳蓝 KN-R的吸附作用   总被引:3,自引:0,他引:3  
研究了青霉菌(Penicillium X5)对活性艳蓝KN—R的吸附作用.通过对培养液的波谱分析和宏观现象的观察,结果表明,在72h内,脱色是由吸附引起的.当染料的浓度为100mg/L时,活菌体对染料的吸附率可达88.66%.本实验还研究了对实际应用和吸附过程有影响的几个因素,包括葡萄糖、NaCl、温度和pH.结果表明:葡萄糖浓度在0-20g/L时,随着葡萄糖浓度的增加,菌体的干重相应增加,说明对活性艳蓝KN—R的吸附具有促进作用,但浓度在10-20g/L时,吸附作用不显著;而随着NaCl浓度(0-2%)的增加,吸附率却显著降低.最佳脱色温度为25℃,pH为4.0.活菌体与死菌体的生物吸附均符合Langmuir方程,活菌体比死菌体具有更好的吸附性能.吸附在菌丝体上的染料可以用甲酵进行洗脱,菌丝球在下次使用前用蒸馏水冲洗至pH中性,此菌丝球可重复使用3次.固8表2参11  相似文献   

20.
黄河"断流”对该河段河水中主要离子化学特征的影响   总被引:3,自引:1,他引:3  
根据全球水质监测计划(GEMS/WaterProgram)和我国水利部黄河流域的水质监测数据,对1970s-1990s期间黄河下游河水主要离子含量的变化趋势及其与“断流”现象之间的关系进行了研究,结果表明,近年来黄河下游“断流现象”的频频出现,主要与枯水期中、上游地区引水量急剧增加有关;黄河的“水质浓化”趋势也主要由中、上游地区大量引水灌溉农田引起,因此,黄河“断流”与“水质浓化”现象是同一人类活动的两个平行的生态后果。  相似文献   

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