石墨烯基磁性复合材料吸附水中亚甲基蓝的研究

建立了一种超声辅助共沉淀法制备磁性Fe3O4/氧化石墨烯(Fe3O4/GO)纳米粒子.透射电镜和磁滞回线研究表明,该复合物具有小的颗粒尺寸和超顺磁性.该磁性纳米材料可以吸附废水中的染料亚甲基蓝,实验研究了溶液pH值、吸附剂的用量、时间和温度对亚甲基蓝去除率的影响.结果表明,pH值在6~9范围内,Fe3O4/GO都能高效地吸附亚甲基蓝.反应过程在前25 min反应速率很快,到180 min内达到吸附平衡.该磁性纳米材料对亚甲基蓝的吸附符合Langmuir吸附等温模型和准二级动力学方程,吸附过程是一个自发和吸热过程.该吸附材料对亚甲基蓝吸附容量高,在313 K时Fe3O4/GO的饱和吸附量为196.5 mg·g-1.另外,可以方便地通过外部磁场分离回收吸附剂,利用过氧化氢可以再生重复使用,是一种优良的吸附染料废水的材料.     

Rapid degradation of dyes in water by magnetic Fe/Fe3O4/graphene composites

Magnetic Fe⁰/Fe₃O₄/graphene has been successfully synthesized by a one-step reduction method and investigated in rapid degradation of dyes in this work. The material was characterized by N₂ sorption–desorption, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), vibrating-sample magnetometer (VSM) measurements and X-ray photoelectron spectroscopy (XPS). The results indicated that Fe⁰/Fe₃O₄/graphene had a layered structure with Fe crystals highly dispersed in the interlayers of graphene, which could enhance the mass transfer process between Fe⁰/Fe₃O₄/graphene and pollutants. Fe⁰/Fe₃O₄/graphene exhibited ferromagnetism and could be easily separated and re-dispersed for reuse in water. Typical dyes, such as Methyl Orange, Methylene Blue and Crystal Violet, could be decolorized by Fe⁰/Fe₃O₄/graphene rapidly. After 20 min, the decolorization efficiencies of methyl orange, methylene blue and crystal violet were 94.78%, 91.60% and 89.07%, respectively. The reaction mechanism of Fe⁰/Fe₃O₄/graphene with dyes mainly included adsorption and enhanced reduction by the composite. Thus, Fe⁰/Fe₃O₄/graphene prepared by the one-step reduction method has excellent performance in removal of dyes in water.     

羟基磷灰石-四氧化三铁-沸石复合材料制备及去除水中刚果红研究

采用可溶性磷酸盐、钙离子、二价铁离子、三价铁离子和天然沸石等材料制备了羟基磷灰石-四氧化三铁-沸石(HAPFe3O4-沸石)复合材料,对该复合材料进行了表征,并考察了该复合材料对水中刚果红的吸附作用.结果表明,HAP-Fe3O4-沸石复合材料对水中的刚果红具备良好的吸附能力.当pH由3增加到4或由7增加到11时,HAP-Fe3O4-沸石复合材料对水中刚果红的去除能力下降;当pH由4增加到7时,对刚果红的吸附能力基本保持不变.HAP-Fe3O4-沸石复合材料对水中刚果红的去除率随吸附剂投加量的增加而增加,而对水中刚果红的单位吸附量则随吸附剂投加量的增加而降低.HAP-Fe3O4-沸石复合材料对水中刚果红的吸附动力学过程可以较好地采用准二级动力学模型加以描述,对刚果红的吸附平衡数据可以采用Langmuir和Freundlich等温吸附模型加以描述.根据Langmuir模型确定的最大吸附容量为117 mg·g-1.(pH 7和303 K).HAP-Fe3O4-沸石复合材料对水中刚果红的吸附是自发吸热并伴随熵增加的过程.当pH为7时,HAP-Fe3O4-沸石复合材料吸附水中刚果红的主要机制包括表面配位作用、氢键作用以及路易斯酸碱反应.采用热再生的方法可以使吸附刚果红后的HAP-Fe3O4-沸石复合材料得到再生,热再生后的复合材料可以循环使用并且对水中刚果红的吸附性能良好.X射线衍射分析结果表明HAP-Fe3O4-沸石复合材料含Fe3O4,磁滞回线结果表明HAP-Fe3O4-沸石复合材料具备较高的磁饱和强度,复合材料吸附刚果红后可以很容易地通过外加磁场的作用快速地与水溶液分离.结果表明,HAP-Fe3O4-沸石复合材料适合作为一种吸附剂去除废水中的刚果红.     

支化聚乙烯亚胺功能化磁性纳米吸附剂的制备及对Cu2+的吸附研究

为解决水体中重金属Cu²⁺污染,本研究首先采用水热法制备得到超顺磁四氧化三铁纳米粒子,然后使用对Cu²⁺具有强络合作用的含有丰富氨基官能团的支化聚乙烯亚胺接枝到纳米粒子表面,得到Fe₃O₄@BPEI磁性纳米吸附剂。采用红外光谱（FTIR）、X射线粉末衍射（XRD）、透射电子显微镜（TEM）等对其结构、尺寸及形貌进行表征。研究了不同吸附因素对吸附剂吸附Cu²⁺的影响,确定了最佳吸附条件,并通过吸附动力学模型和吸附等温线模型进一步探讨吸附机理。结果表明：支化聚乙烯亚胺成功接枝到四氧化三铁纳米粒子表面。最佳吸附条件为pH=6.0、吸附平衡时间为40 min、吸附剂用量为10 mg。通过实验数据拟合,Fe₃O₄@PEI吸附Cu²⁺的过程符合Langmuir等温吸附方程和拟二级动力学模型,表明吸附过程为化学吸附控制的单分子层覆盖,在303 K时,模型理论饱和吸附量为141.24 mg/g。表明支化聚乙烯亚胺修饰的磁性纳米吸附剂对Cu²⁺具有较强的吸附能力,对水体中Cu²⁺的去除具有一定的应用前景。     

Fe3O4@SiO2-Chitosan的制备及其对水中Cu2+的吸附效能研究

以SiO_2包覆Fe_3O_4,戊二醛为交联剂,交联壳聚糖(Chitosan, CTS),制得Fe_3O_4@SiO_2-Chitosan复合磁性纳米粒子.以Fe_3O_4和Fe_3O_4@SiO_2为对照,采用X射线衍射、透射电镜和傅立叶红外光谱对其进行表征分析,并测定了投加量、pH值、吸附时间和温度等因素对Cu~(2+)吸附效果的影响,从动力学、热力学以及再生回用性能评价等方面对其吸附性能进行了探究.结果表明Fe_3O_4@SiO_2-Chitosan对Cu~(2+)的吸附过程符合准二级吸附动力学模型和Langmuir模型,为自发、放热、优惠型的单分子层化学吸附.在pH为6.0, 298 K下达到最大吸附量154.8 mg·g~(-1),吸附解吸4次后吸附容量变化不大,说明Fe_3O_4@SiO_2-Chitosan具有较高的吸附容量,可作为处理含铜废水和回收铜的高效吸附剂.     

改性磁性纳米颗粒固定内生菌Bacillus nealsonii吸附废水中Cd2+的特性研究

从重金属超累积植物龙葵体内提取内生菌Bacillus nealsonii,采用二氧化硅改性纳米Fe_3O_4颗粒与海藻酸钠将其包埋交联进行固定化,制得一种新型球状生物吸附剂,并应用于废水中Cd~(2+)的吸附处理.同时,通过正交实验研究了该球状生物吸附剂的最佳制备条件和吸附处理条件,并采用扫描电镜等表征手段与构建吸附动力学考察了其吸附特征.结果表明,球状生物吸附剂的最佳制备条件为:改性纳米Fe3O4颗粒质量分数为0.1%,海藻酸钠质量分数为8.0%,菌液接种量为0.4%,交联时间为2 h;其最佳吸附处理条件为p H=6、吸附时间12 h、吸附剂用量(干重)2.5 g·L-1,在Cd~(2+)初始浓度为50 mg·L-1时的吸附率可达96%以上.研究发现,球状生物吸附剂的内外部结构孔隙率较大,有利于促进Cd~(2+)的吸附.该吸附过程遵循准二级反应动力学,以化学吸附为主,符合Freundlich等温吸附模型,最大单分子吸附量可达13.02 mg·g-1.解吸实验结果表明,该吸附剂具有较好的可重复利用性.     

Removal of tetracycline from aqueous solution by a Fe3O4 incorporated PAN electrospun nanofiber mat

Pollution of antibiotics, a type of emerging contaminant, has become an issue of concern, due to their overuse in human and veterinary application, persistence in environment and great potential risk to human and animal health even at trace level. In this work, a novel adsorbent, Fe₃O₄ incorporated polyacrylonitrile nanofiber mat (Fe-NFM), was successfully fabricated via electrospinning and solvothermal method, targeting to remove tetracycline (TC), a typical class of antibiotics, from aqueous solution. Field emission scanning electron microscopy and X-ray diffraction spectroscopy were used to characterize the surface morphology and crystal structure of the Fe-NFM, and demonstrated that Fe-NFM was composed of continuous, randomly distributed uniform nanofibers with surface coating of Fe₃O₄ nanoparticles. A series of adsorption experiments were carried out to evaluate the removal efficiency of TC by the Fe-NFM. The pseudo-second-order kinetics model fitted better with the experimental data. The highest adsorption capacity was observed at initial solution pH 4 while relative high adsorption performance was obtained from initial solution pH 4 to 10. The adsorption of TC on Fe-NFM was a combination effect of both electrostatic interaction and complexation between TC and Fe-NFM. Freundlich isotherm model could better describe the adsorption isotherm. The maximum adsorption capacity calculated from Langmuir isotherm model was 315.31 mg/g. Compared to conventional nanoparticle adsorbents which have difficulties in downstream separation, the novel nanofiber mat can be simply installed as a modular compartment and easily separated from the aqueous medium, promising its huge potential in drinking and wastewater treatment for micro-pollutant removal.     

膨润土-白云石复合吸附剂对Fe2+和Mn2+的吸附性能

针对煤矿排出的大量含重金属离子的酸性矿山废水污染问题,采用自制膨润土-白云石复合颗粒吸附剂对含Fe2+和Mn2+的酸性矿山废水进行吸附试验研究。结果表明:膨润土-白云石复合颗粒吸附剂释放总碱度达118.39mg/g(以CaCO3计),可中和酸性矿山废水;随着废水中Fe2+和Mn2+浓度增加,膨润土复合颗粒吸附剂的吸附量在不断增加,且大于原膨润土颗粒吸附剂;建立了膨润土复合颗粒吸附剂对Fe2+和Mn2+的吸附等温式和吸附动力学方程式:膨润土复合颗粒吸附剂对Fe2+的吸附符合BET吸附,对Mn2+的吸附符合Freundlich吸附,对Fe2+、Mn2+的吸附动力学均符合准二级动力学。膨润土-白云石复合颗粒吸附剂既能释放碱度、又对Fe2+和Mn2+具有优良的吸附性能,可作为处理含重金属离子酸性矿山废水的绿色环保矿物材料应用于实际。     

常规金属离子对Fe3O4磁性纳米颗粒悬浮和沉降的影响

水体中的有机质、无机盐及酸碱度是影响纳米材料迁移转化的主要因素.考察了Na~+、Mg~(2+)、Ca~(2+)、Sr~(2+)和Ba~(2+)对Fe_3O_4磁性纳米材料(Magnetic Nanoparticles,MNPs)的沉降作用.结果表明,Fe_3O_4MNPs的沉降作用是水体pH、金属离子化合价、离子强度共同影响的结果.整体上,碱土金属离子较Na~+更能加速Fe_3O_4MNPs的沉降.当pH为5.0时,浓度低于1.0 mmol·L~(-1)的Na~+、Mg~(2+)和Ca~(2+)有助于Fe_3O_4MNPs的悬浮;当浓度大于1.0 mmol·L~(-1)时,较强的离子强度促使Fe_3O_4MNPs团聚,发生沉降.当pH为9.0时,碱土金属离子较Na~+更能促使Fe_3O_4MNPs聚沉.因此,纳米颗粒在水体中的扩散和聚沉需要综合考虑金属离子种类和浓度.     

核-壳表面磁性印迹聚合物的制备及其对水中双酚A的特异性去除

采用表面印迹技术制备了核-壳结构的磁性分子印迹聚合物(Fe3O4@SiO2-MIPs),在外磁场作用下该吸附剂很容易实现固-液分离.采用X-射线衍射(XRD)、扫描电镜(SEM)和傅里叶变换红外光谱(FT-IR)对产物的结构进行了表征.通过平衡吸附实验与斯卡查德(Scatchard)分析证实了Fe3O4@SiO2-MIPs对双酚A的吸附选择性.Freundlich模型拟合吸附等温线的相关系数R2=0.995 2;准二级动力学模型很好地拟合了吸附动力学,相关系数R2达到了0.999 9.在弱酸性条件下,制备的印迹材料表现出高吸附效率和快速的吸附动力学,达到90%的去除率仅需40 min;各种离子的存在不影响双酚A的吸附率;与非印迹聚合物(Fe3O4@SiO2-NIPs)比较,Fe3O4@SiO2-MIPs对湖水中加标的双酚A表现出显著的亲和性;7次的重复使用而性能没有明显下降证明了Fe3O4@SiO2-MIPs的可重复使用性.     

Cu(II), Fe(III) and Mn(II) combinations as environmental stress factors have distinguishing effects on Enterococcus hirae

Pollution by various heavy metals as environmental stress factors might affect bacteria. It was established that iron (Fe(III)), manganese (Mn(II)) and copper (Cu(II)) ion combinations caused effects on Enterococcus hirae that differed from the sum of the effects when the metals were added separately. It was shown that the Cu^2 +–Fe^3 + combination decreased the growth and ATPase activity of membrane vesicles of wild-type E. hirae ATCC9790 and atpD mutant (with defective F_oF₁-ATPase) MS116. Addition of Mn^2 +–Fe^3 + combinations within the same concentration range had no effects on growth compared to control (without heavy metals). ATPase activity was increased in the presence of Mn^2 +–Fe^3 +, while together with 0.2 mmol/L N,N′-dicyclohexylcarbodiimide (DCCD), ATPase activity was decreased compared to control (when only 0.2 mmol/L DCCD was present). These results indicate that heavy metals ion combinations probably affect the F_OF₁-ATPase, leading to conformational changes. Moreover the action may be direct or be mediated by environment redox potential. The effects observed when Fe^3 + was added separately disappeared in both cases, which might be a result of competing processes between Fe^3 + and other heavy metals. These findings are novel and improve the understanding of heavy metals ions effects on bacteria, and could be applied for regulation of stress response patterns in the environment.     

纳米磁性颗粒Fe3O4用于吸附水相中酸性红73及其机理研究

利用纳米磁性颗粒处理含酸性红73废水以利于进一步降低其色度.实验以酸洗废液制备的纳米磁粉Fe3O4作为吸附剂,并通过单因素实验和吸附动力学及热力学的分析探讨其对酸性红73的表面吸附的吸附机理.结果表明:纳米磁粉Fe3O4对酸性红73的表面吸附符合假二级动力学方程,其反应活化能为49.05 kJ·mol-1.磁粉对酸性红73的吸附是快速的表面物理吸附,其表面吸附行为符合Langmuir等温吸附式,是放热和熵减的自发过程.在温度T为303 K的条件下,20 min内的饱和吸附量能可达到40.1 mg·g-1.因此,用纳米磁粉Fe3O4吸附处理含偶氮染料废水,吸附平衡可在很短的时间内实现.     

四氧化三铁/聚乙烯亚胺纳米颗粒的制备及除磷性能的研究

采用化学共沉淀法,以聚乙烯亚胺(PEI)为改性剂,制备了聚乙烯亚胺改性的纳米四氧化三铁复合材料(Fe3O4/PEI).Zeta电位、透射电镜和FTIR表征结果显示,PEI修饰提高了纳米Fe3O4在水中的分散性和稳定性,同时也增强了其表面正电荷,从而提高了Fe3O4对水中磷酸根的去除能力.在磷酸根初始浓度为50 mg·L~(-1),Fe3O4/PEI投加量为200 mg,p H=3,温度为25℃的条件下,Fe3O4/PEI对100 m L磷酸根的吸附去除率达到91%.吸附过程在3 h内达到平衡.吸附等温数据表明,该吸附过程符合Langmuir吸附等温方程,可决系数R2达到0.99,最大吸附量为29.88 mg·L~(-1).Fe3O4/PEI复合材料重复利用性好,在第5次吸附-解析后还能保持对磷酸根75%以上的吸附去除率.磷的解析效率随着p H增加而增加,在p H=13时,解析效率达到65%.     

High capacity adsorption of antimony in biomass-based composite and its consequential utilization as battery anode

Antimony is more than an emerging pollutant in water but a scare resource. In this study, we report an adsorbent with the record capacity so far from the balanced view of Sb(III) and Sb(V). The composite adsorbent was fabricated by encapsulating hollow Fe₃O₄ nanosphere with the EDTA grafted chitosan, and it has superhigh adsorption capacity of for 657.1 mg/g for Sb(III) and 467.3 mg/g for Sb(V), respectively. The mechanism study reveals that the adsorption of Sb initializes from the Fe₃O₄, propagates along the chitosan with hydrogen bond, and terminates at the inner sphere complex with the EDTA moiety in the adsorbent. In view of the ultra-high adsorption capacity of the adsorbent, the recovered adsorbent that contains abundant (>36.4%) highly dispersed antimony nanoparticles (600-FCSE-Sb) is applied to Li-ion battery anode after reduction. This article provides a new idea for connecting water treatment and electric energy storage.     

水合氧化铝负载的磁性核/壳结构Fe3O4@SiO2纳米颗粒对水中磷的去除及再利用

在磁铁矿纳米颗粒表面包被硅壳后再包被水合氧化铝,制备了具备核壳结构的磁性纳米颗粒除磷吸附剂(磁性氧化铝),通过XRD、TEM、VSM、BET比表面积测定进行了表征.XRD和TEM结果显示了核壳结构的存在,其饱和磁化强度达56.00 emu·g~(-1),比表面积达47.27 m~2·g~(-1).Langmuir模型计算的磷最大吸附量为12.90 mg·g~(-1),且在25℃和50℃下均保持稳定,反应快速,40min磷去除率达96%以上.磁性纳米吸附剂对磷的吸附与pH关系密切,在p H为5~9时磷去除率达90%以上.采用实际污水实验,最佳投量为1.25 kg·t~(-1).吸附-脱附-再生实验结果表明,磷吸附率随循环次数增加稍有下降,吸附的磷可以通过1 mol·L~(-1)的NaOH脱附,脱附率为90%左右,且吸附剂可以进行再生,具有反复利用和回收磷资源的潜力.     

Using a novel adsorbent macrocyclic compound cucurbit[8]uril for Pb removal from aqueous solution

In this study, cucurbit[8]uril (CB[8]) was utilized as a kind of new adsorbent to remove Pb^2 + ions from aqueous solution. With the solution pH increased from 2 to 6, the removal efficiency of adsorption increased from 55.6% to 74.5%correspondingly. The uptake of Pb^2 + increased rapidly in the initial 30 min, and then the adsorption rate became slower. The Pseudo-second order model could be used to interpret the adsorption kinetics satisfactorily; and the rate determining step in Pb^2 + adsorption onto CB[8] was the external mass transfer step. Equilibrium isotherm study reveals that the Langmuir model gave a better fitting result than Freundlich model. The maximum adsorption capacity calculated by the Langmuir model was 152.67 mg/g for 298 K, 149.70 mg/g for 313 K and 136.42 mg/g for 323 K, respectively. The adsorption is a spontaneous process of exothermic nature. The effect of the adsorbent dosage and the influences of solution pH and co-existing cations were also investigated. The CB[8] was synthesized and characterized by ¹H NMR, IR, ESI-MS spectra, SEM-EDAX, Zeta-potential and BET-analysis. The adsorption mechanism was due to the coordination between CB[8] molecule and Pb^2 + ions.     

Removal of ammonium ion from water by Na-rich birnessite: Performance and mechanisms

Na-rich birnessite (NRB) was synthesized by a simple synthesis method and used as a high-efficiency adsorbent for the removal of ammonium ion (NH₄⁺) from aqueous solution. In order to demonstrate the adsorption performance of the synthesized material, the effects of contact time, pH, initial ammonium ion concentration, and temperature were investigated. Adsorption kinetics showed that the adsorption behavior followed the pseudo second-order kinetic model. The equilibrium adsorption data were fitted to Langmuir and Freundlich adsorption models and the model parameters were evaluated. The monolayer adsorption capacity of the adsorbent, as obtained from the Langmuir isotherm, was 22.61 mg NH₄⁺-N/g at 283 K. Thermodynamic analyses showed that the adsorption was spontaneous and that it was also a physisorption process. Our data revealed that the higher NH₄⁺ adsorption capacity could be primarily attributed to the water absorption process and electrostatic interaction. Particularly, the high surface hydroxyl-content of NRB enables strong interactions with ammonium ion. The results obtained in this study illustrate that the NRB is expected to be an effective and economically viable adsorbent for ammonium ion removal from aqueous system.     

Insight into the adsorption of tetracycline onto amino and amino–Fe functionalized mesoporous silica: Effect of functionalized groups

In order to study the influences of functionalized groups onto the adsorption of tetracycline (TC), we prepared a series of amino and amino–Fe^3 + complex mesoporous silica adsorbents with diverse content of amino and Fe^3 + groups (named N,N-SBA15 and Fe-N,N-SBA15). The resulting mesoporous silica adsorbents were fully characterized by X-ray powder diffraction, Fourier transform infrared spectrometer and N₂ adsorption/desorption isotherms. Furthermore, the effects of functionalized groups on the removal of TC were investigated. The results showed that the periodic ordered structure of SBA-15 was maintained after modification of amino/Fe^3 + groups. The functionalized amino groups decreased the adsorption capacity while the coordinated Fe^3 + increased the adsorption capacity. The adsorption kinetics of TC fitted pseudo-second-order model well and the equilibrium was achieved quickly. The adsorption isotherms fitted the Langmuir model well and with the Fe^3 + content increased from 3.93% to 8.26%, the Q_max of the adsorbents increased from 102 to 188 mmol/kg. The solution pH affected the adsorption of TC onto amino complex adsorbents slightly while influenced the adsorption onto Fe-amine complex adsorbents greatly. The adsorption of TC on SBA15 and N,N-SBA15 may be related to the formation of outer-sphere surface complexes, while the adsorption of TC onto Fe-N,N-SBA15 was mainly attributed to the inner-sphere surface complexes. This study could offer potential materials that have excellent adsorption behavior for environmental remediation and suggested useful information for the preparing other adsorbents in environmental applications.     

Reuse of Fenton sludge as an iron source for NiFe2O4 synthesis and its application in the Fenton-based process

The potentially hazardous iron-containing sludge from the Fenton process requires proper treatment and disposal, which often results in high treatment cost. In this study, a novel method for the reuse of Fenton sludge as an iron source for the synthesis of nickel ferrite particles(NiFe_2O_4) is proposed. Through a co-precipitation method followed by sintering at 800°C, magnetic NiFe_2O_4 particles were successfully synthesized, which was confirmed by powder X-ray diffraction(XRD), scanning electronic microscopy(SEM), energy dispersive spectroscopy(EDS), Fourier transform infrared spectroscopy(FT-IR) and Raman spectroscopy. The synthesized NiFe_2O_4 could be used as an efficient catalyst in the heterogeneous Fenton process. In phenol degradation with H_2O_2 or NiFe_2O_4 alone, the phenol removal efficiencies within the reaction time of 330 min were as low as 5.9% ± 0.1% and 13.5% ±0.4%, respectively. However, in the presence of both NiFe_2O_4 and H_2O_2, phenol removal efficiency as high as 95% ± 3.4% could be achieved, indicating the excellent catalytic performance of NiFe_2O_4 in the heterogeneous Fenton process. Notably, a rapid electron exchange between_Ni II and_Fe III ions in the NiFe_2O_4 structure could be beneficial for the Fenton reaction. In addition, the magnetic catalyst was relatively stable, highly active and recoverable, and has potential applications in the Fenton process for organic pollutant removal.     

淀粉稳定Fe3O4纳米粒子对水中As(V)的吸附特性研究

以可溶性淀粉作为稳定剂制备纳米Fe_3O_4粒子,探讨了反应时间、p H值、初始砷浓度和腐殖酸对Fe_3O_4纳米粒子吸附水体中As(V)的吸附效果影响.实验结果表明,淀粉稳定的Fe_3O_4纳米粒子对水体中As(V)的吸附动力学过程符合准二级动力学,吸附等温线符合Langmuir吸附模型;吸附容量随着溶液p H的增加逐渐降低,在p H为8.0的弱碱性水体中对As(V)的最大吸附容量可达202.56 mg·g~(-1);此外,腐殖酸(HA)能降低纳米粒子对As(V)的吸附能力.