柱生物曝气法吸附处理含铬废水

利用复合生物吸附剂FY01与活性污泥作为吸附材料，探讨了柱式生物曝气法对高浓度含铬电镀废水的生物吸附效果。研究结果表明，FY01性能稳定，耐进水pH冲击能力较强。当进水pH=2—5、流速为500mL／h时，10gFY01和5g活性污泥联合处理60．4mg／L含铬电镀废水2h后，铬的去除率达78％以上；在4℃冰箱和23—28℃实验室保存50d的FY01对铬的去除分别在78％～83％和77％-84％之间。柱式生物曝气吸附法对含铬废水的处理效果理想，运行稳定。串联处理2000mL总Cr、Cu^2＋和COD浓度分别为60．4、4．51和48．2mg／L的电镀废水2h后，去除率分别高达92．1％、99．2％和71．4％。     

改性芦苇生物炭对水中硫酸盐的吸附性能及机理

水中过高浓度硫酸盐赋存会对水生环境产生一定的影响。为此,选取芦苇秸秆作为生物炭原料,通过添加煤矸石共热解对生物炭进行了改性,采用扫描电子显微镜(SEM)、氮气吸附脱附法(BET)和傅里叶红外光谱(FTIR)等手段对生物炭的物理化学性质进行了分析,考察了pH、吸附剂投加量、吸附时间和初始浓度对水中硫酸盐吸附性能的影响。结果表明：改性后生物炭(MBC)的吸附效果优于未改性生物炭(OBC);MBC的粗糙程度大于OBC,MBC拥有更大的比表面积和更多的孔隙结构,其比表面积为改性前的2.4倍;对吸附过程进行吸附动力学和吸附等温模型拟合,发现准一级动力学模型和Langmuir模型可以更好的描述MBC对硫酸盐的吸附行为,表明吸附过程以静电吸附和单分子层吸附为主。当pH为2、投加量为8 g·L^-1时改性材料吸附效果最好,最大吸附量可达29.69 mg·g^-1,且经过5次再生吸附后,硫酸盐去除率仍能达到50%以上。因此,改性后的生物炭可作为去除水体中硫酸盐的良好材料。     

改性松针对水中壬基酚的吸附

研究了由乙醇改性后的松针对水中壬基酚的吸附去除效果;探讨了其吸附过程的热力学和动力学行为;考察了pH、温度对吸附效果的影响。实验结果表明,改性松针对水中壬基酚具有很好的吸附能力,当壬基酚浓度为10 mg·L-1,溶液30 mL、吸附剂投加量为1 g、温度为25℃、pH值为7时,35 min达到吸附饱和,实验饱和吸附量为0.279 mg·g-1,吸附去除率为93.3%;吸附过程符合准一级动力学方程,并能够同时满足Langmuir和Freundlich吸附等温吸附模型。     

柱生物曝气法吸附处理含铬废水

利用复合生物吸附剂FY01与活性污泥作为吸附材料,探讨了柱式生物曝气法对高浓度含铬电镀废水的生物吸附效果.研究结果表明,FY01性能稳定,耐进水pH冲击能力较强.当进水pH=2～5、流速为500 mL/h时,10 g FY01和5 g活性污泥联合处理60.4 mg/L含铬电镀废水2 h后,铬的去除率达78%以上;在4℃冰箱和23～28℃实验室保存50 d的FY01对铬的去除分别在78%～83%和77%～84%之间.柱式生物曝气吸附法对含铬废水的处理效果理想,运行稳定.串联处理2000 mL总Cr、Cu2 和COD浓度分别为60.4、4.51和48.2 mg/L的电镀废水2 h后,去除率分别高达92.1%、99.2%和71.4%.     

低成本海水改性生物炭颗粒的制备及其对水中磷的动态吸附性能

针对生物炭除磷领域中缺乏兼具经济性和实用性的Mg改性生物炭的问题,以海水为廉价Mg源,制备了海水改性生物炭颗粒(SBC-g),探究了其物理化学特性和吸附磷酸盐机理,考察了柱高、流量和初始质量浓度对SBC-g动态吸附磷酸盐的影响及对含磷养殖尾水的处理效果,并对SBC-g进行了经济性分析。结果表明,改性后SBC-g表面负载的Mg(OH)₂纳米片可增加吸附的活性位点,增大了介孔的孔径和孔容,改变了表面电荷性质,从而提高了其对磷酸盐的吸附容量。在一定范围内,柱高的增加或流量和初始质量浓度的降低均可延长穿透时间。Thomas模型对穿透曲线拟合良好(R² > 0.919),可以较为准确地反映动态吸附过程。SBC-g吸附柱对养殖尾水具有良好的除磷效果,在最佳条件下吸附柱的穿透时间为589 min,磷饱和吸附量为1 051 mg·kg⁻¹。SBC-g的生产成本约为2.65 元·kg⁻¹,和其他除磷吸附剂相比具有较大的价格优势,兼具经济性和实用性。该研究结果可为Mg改性生物炭的制备及其在水体磷污染治理领域的实际应用提供参考。     

改性丝瓜络纤维对水体日落黄的吸附特性

采用化学改性的方法将丝瓜络制备为阴离子吸附剂,并将其用于水体日落黄(SY)染料的吸附,分别考察了吸附剂的用量、日落黄染料的初始浓度(C0)、pH值、温度(K)、时间(T)5个因素对吸附效果的影响。通过模拟吸附等温曲线、吸附动力学以及热力学方程并通过比表面积(BET)和红外光谱(FTIR)分析改性丝瓜络吸附染料前后和丝瓜络改性前后的变化情况以此探究其吸附机理。结果表明,pH对吸附效果影响不明显;最大吸附量随温度升高而增大,在298 K温度时最大吸附量达到137 mg/g,是未改性丝瓜络的9.78倍。Langmuir方程拟合吸附过程描述最好,吸附类别为化学吸附。吸附过程符合伪二级动力学,是一个自发和吸热的过程。改性丝瓜络可以有效去除水体中的日落黄染料。     

板栗壳对重金属Cr（Ⅵ）吸附性能的研究

从废弃的植物材料中筛选出一种Cr(Ⅵ)高效吸附剂——板栗壳。研究了pH、接触时间、板栗壳用量、温度和Cr (Ⅵ)初始浓度对Cr(Ⅵ)吸附活性的影响。结果表明, 板栗壳的最佳pH为2～3。在pH 2时,Cr(Ⅵ)的去除率达99.7%。在15～35℃的温度范围内,板栗壳对Cr(Ⅵ)的去除率随温度的升高而增加。30℃时,Cr(Ⅵ)的去除率可达99%。板栗壳用量对Cr(Ⅵ)的去除有明显影响。由0.2 g增加到0.4 g时, Cr(Ⅵ)的去除率从90.6%提高到99%。在较宽的铬初始浓度范围内,板栗壳对Cr (Ⅵ)有明显的去除作用。     

活性矸—碘吸附体系的研究

研究了新型吸附剂－活性矸的吸附行为，结果表明，活性矸等温吸附符合Ｆｒｅｕｎｉｃｈ吸附等温方程式，吸附动力学可用Ｂａｎｇｈａｍ吸附速率方程描述，并且可利用Ｂｏｄｙ公式确定活性矸－碘吸附体系的液相有效扩散系统（Ｄｉ）。     

高锰酸钾改性生物炭对水中噻虫胺吸附性能及机理

以700 ℃热解制备的杉木生物炭(BC)为原料,采用高锰酸钾高温氧化法制备了改性生物炭(MnO_x-BC),考察了其对广泛使用的新烟碱类杀虫剂噻虫胺的强化去除及作用机理。结果表明,高锰酸钾改性生物炭对噻虫胺的去除能力较原始生物炭有所提高,Langmuir模型拟合得到MnO_x-BC对噻虫胺的最大吸附容量达到37 mg·g⁻¹。MnO_x-BC对噻虫胺的吸附动力学符合准二级动力学方程,颗粒内扩散模型拟合显示吸附过程分为3个阶段。MnO_x-BC对噻虫胺的吸附过程属于单分子层吸附,不同pH条件下MnO_x-BC比BC具有更好的吸附稳定性,共存离子Ca²⁺对MnO_x-BC吸附抑制作用大于Na⁺。MnO_x-BC对噻虫胺的吸附机理主要包括孔隙填充、π-π电子供体-受体相互作用、氢键作用和静电作用。     

改性透辉石对饮用水中余氯的吸附机理

将透辉石和碳酸钙在高温下反应活化,对透辉石进行改性,探讨了改性透辉石对余氯的吸附性能。利用X射线衍射（XRD）、扫描电镜（SEM）和X射线光电子能谱（XPS）对吸附前后的改性透辉石进行表征。考察了此吸附过程的吸附平衡、动力学和热力学。实验结果表明,吸附后的残渣XRD图谱出现了带羟基的Ca4（Si3O9）（OH）2,吸附前后的SEM图表面发生明显变化,吸附残渣的XPS图中有+1价的Cl。Freundlich和Langmuir方程都呈现良好的拟合度,改性透辉石的单分子层最大吸附量是6.974 mg·g-1,热力学平衡方程计算的ΔG0S0>0,说明吸附是自发进行的、熵增反应;从293 K至303 K时ΔH0值为3.43 kJ·mol-1,该阶段的吸附反应是吸热的;温度303 K至313 K阶段,ΔH0值为-9.00 kJ·mol-1,吸附反应是放热的。对余氯的吸附机理是斜方硅钙石Ca4（Si3O9）（OH）2的羟基和ClO-发生交换作用。     

Adsorption of phenolic compounds from aqueous solutions by a water-compatible hypercrosslinked polymeric adsorbent

A water-compatible hypercrosslinked polymeric adsorbent (NJ-8) for adsorbing and removing phenolic compounds from their aqueous solutions was prepared. This product can be used directly without a wetting process. Its adsorption property toward four phenolic compounds, phenol, p-cresol, p-chlorophenol, and p-nitrophenol was tested using the commercial Amberlite XAD-4 as a reference. The capacities of equilibrium adsorption for all four phenolic compounds on the NJ-8 from their aqueous solutions are around two times as high as that of Amberlite XAD4 within the temperature range 283-323 K, which may contribute to their micropore structure and the partial polarity on the network. Freundlich isotherm equations, as well as relative adsorption capacities and isosteric adsorption enthalpies for the four phenolic compounds, indicate that the adsorption of phenolic compounds on the NJ-8 resin is a physical adsorption process. Mini-column adsorption studies for phenol on Amberlite XAD4 and NJ-8 resins show that the breakthrough adsorption capacities are 0.54 and 0.99 mmol/ml, and the total capacities are 0.62 and 1.37 mmol/ml, while no extra acetone was needed to remove the adsorbed phenol from NJ-8 as from Amberlite XAD4.     

Oxidized multiwalled carbon nanotubes as adsorbent for the removal of manganese from aqueous solution

A batch adsorption process was applied to investigate the removal of manganese from aqueous solution by oxidized multiwalled carbon nanotubes (MWCNTs). In doing so, the thermodynamic, adsorption isotherm, and kinetic studies were also carried out. MWCNT with 5–10-nm outer diameter, surface area of 40–600 m²/g, and purity above 95 % was used as an adsorbent. A systematic study of the adsorption process was performed by varying pH, ionic strength, and temperature. Manganese-adsorbed MWCNT was characterized by Raman, FTIR, X-ray diffraction, XPS, SEM, and TEM. The adsorption efficiency could reach 96.82 %, suggesting that MWCNT is an excellent adsorbent for manganese removal from water. The results indicate that second-order kinetics model was well suitable to model the kinetic adsorption of manganese. Equilibrium data were well described by the typical Langmuir adsorption isotherm. Thermodynamic studies revealed that the adsorption reaction was spontaneous and endothermic process. The experimental results showed that MWCNT is an excellent manganese adsorbent. The MWCNTs removed the manganese present in the water and reduced it to a permissible level making it drinkable.     

Activated carbon from industrial solid waste as an adsorbent for the removal of Rhodamine-B from aqueous solution: kinetic and equilibrium studies

The activated carbon was prepared using industrial solid waste called sago waste and physico-chemical properties of carbon were carried out to explore adsorption process. The effectiveness of carbon prepared from sago waste in adsorbing Rhodamine-B from aqueous solution has been studied as a function of agitation time, adsorbent dosage, initial dye concentration, pH and desorption. Adsorption equilibrium studies were carried out in order to optimize the experimental conditions. The adsorption of Rhodamine-B onto carbon followed second order kinetic model. Adsorption data were modeled using both Langmuir and Freundlich classical adsorption isotherms. The adsorption capacity Q0 was 16.12 mg g(-1) at initial pH 5.7 for the particle size 125-250 microm. The equilibrium time was found to be 150 min for 10, 20 mg l(-1) and 210 min for 30, 40 mg l(-1) dye concentrations, respectively. A maximum removal of 91% was obtained at natural pH 5.7 for an adsorbent dose of 100mg/50 ml of 10 mg l(-1) dye concentration and 100% removal was obtained when the pH was increased to 7 for an adsorbent dose of 275 mg/50 ml of 20 mg l(-1) dye concentration. Desorption studies were carried out in water medium by varying the pH from 2 to 10. Desorption studies were performed with dilute HCl and show that ion exchange is predominant dye adsorption mechanism. This adsorbent was found to be both effective and economically viable.     

去除水中全氟辛基磺酸的纳米吸附剂的制备及性能表征

实验研究了去除水中全氟辛基磺酸(PFOS)的纳米吸附剂的制备方法,并对其性能进行表征.研究结果表明:单体(4-乙烯基吡啶)含量对吸附剂去除PFOS的效果影响显著;而聚合状态、聚合液含水率、有机溶剂和交联剂的种类仅对吸附剂形态和比表面积有一定影响,但对吸附剂去除PFOS的效果影响不大.红外光谱揭示了单体和交联剂的有效聚合,ζ电位的测定则证实了单体和PFOS是由于静电作用而结合.     

Modelling of the acid-base properties of natural and synthetic adsorbent materials used for heavy metal removal from aqueous solutions

In this paper a comparison about kinetic behaviour, acid-base properties and copper removal capacities was carried out between two different adsorbent materials used for heavy metal removal from aqueous solutions: an aminodiacetic chelating resin as commercial product (Lewatit TP207) and a lyophilised bacterial biomass of Sphaerotilus natans. The acid-base properties of a S. natans cell suspension were well described by simplified mechanistic models without electrostatic corrections considering two kinds of weakly acidic active sites. In particular the introduction of two-peak distribution function for the proton affinity constants allows a better representation of the experimental data reproducing the site heterogeneity. A priori knowledge about resin functional groups (aminodiacetic groups) is the base for preliminary simulations of titration curve assuming a Donnan gel structure for the resin phase considered as a concentrated aqueous solution of aminodiacetic acid (ADA). Departures from experimental and simulated data can be interpreted by considering the heterogeneity of the functional groups and the effect of ionic concentration in the resin phase. Two-site continuous model describes adequately the experimental data. Moreover the values of apparent protonation constants (as adjustable parameters found by non-linear regression) are very near to the apparent constants evaluated by a Donnan model assuming the intrinsic constants in resin phase equal to the equilibrium constants in aqueous solution of ADA and considering the amphoteric nature of active sites for the evaluation of counter-ion concentration in the resin phase. Copper removal outlined the strong affinity of the active groups of the resin for this ion in solution compared to the S. natans biomass according to the complexation constants between aminodiacetic and mono-carboxylic groups and copper ions.     

Comparison of commercial peroxidases for removing phenol from water solutions

This paper describes a comparison between horseradish peroxidase (HRP) and soybean peroxidase (SBP), the two most widely used commercial peroxidases for the removal of phenol from wastewater. Both enzymes achieve maximal removal efficiency in a neutral pH medium although they are still quite active in a pH range of between 6.0 and 8.0. The fact that both enzymes show similar phenol elimination levels at any temperature between 25 and 40 degrees C is also of interest. Studies were carried out in the absence and presence of different concentrations of a stabilisation additive, polyethylene glycol (PEG), in an attempt to optimise the phenol elimination procedure. The final choice of peroxidase will depend on the characteristics of the effluent, operational requirements and on economic considerations. Our findings show that HRP acts faster than SBP but is more susceptible to inactivation, although it is better protected by PEG. In consequence HRP will be the most suitable choice but the addition of a sufficient amount of PEG is critical.     

自组装单层材料对水中除草剂西玛津的吸附研究

以SiO2微粉为基底制备了终端接有SO3H基的自组装单层材料(SO3H/SiO2),研究了其吸附水中弱碱性除草剂西玛津的性能及机制.结果表明,SO3H/SiO2能有效清除水中西玛津,如0.12 g SO3H/SiO2对20 mL 1.4 mg/L西玛津吸附3 h,其吸附率达91%.吸附等温实验数据用Langmuir吸附等温式拟合效果优于Freundlich吸附等温式.吸附机制为静电相互作用,西玛津分子大部分以分子形式到达自组单层的表面,SO3H基电离的H 使西玛津质子化而带正电,从而与-SO3-通过静电作用而保留在SO3H/SiO2的表面.     

白云石矿物对水溶液中Cu2+、Pb2+吸附的动力学和热力学

采用静态实验方法研究了白云石对水溶液中Cu2+、Pb2+的吸附特性,通过批实验考察了反应时间、溶液初始浓度、pH值、离子强度、温度以及固液比等因素对吸附的影响,探讨了白云石对Cu2+、Pb2+的吸附动力学、热力学规律及其反应机制。实验结果显示:白云石对Cu2+、Pb2+的吸附在24 h达到平衡,对Pb2+的吸附量大于Cu2+,伪二级和双常数动力学方程分别能较好地拟合白云石对Cu2+、Pb2+的吸附;在一定条件下,白云石对Cu2+、Pb2+的去除率与溶液初始浓度呈反比,与固液比呈正比;吸附等温方程符合Langmuir模型,为单分子层吸附;溶液pH值对吸附行为影响显著,在溶液pH=6~7时,吸附效果最好,离子强度对吸附影响甚微;白云石对Cu2+、Pb2+的吸附属于吸热反应,反应自发进行,高温促进白云石的吸附行为。