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1.
The adsorption of three cationic dyes (rhodamine B, RB; crystal violet, CV; and malachite green, MG) onto termite feces, a low‐cost adsorbent, was investigated. The adsorbent was characterized by IR spectroscopy, point of zero charge measurement, and the Boehm titration method. The adsorption follows the pseudo‐second‐order kinetic model and the Langmuir–Freundlich isotherm with maximum adsorption capacities of 95.53 mg g?1 (RB), 75.71 mg g?1 (CV), and 44.78 mg g?1 (MG). The study of thermodynamics showed that the adsorption is a spontaneous and endothermic process. This works suggest that termite feces can be used as a new low‐cost adsorbent for cationic dye removal.  相似文献   

2.
Waste beer yeast was modified by pyromellitic dianhydride to improve its adsorption capacity for rhodamine B (RhB). Results showed that the adsorption capacity of the modified biomass for RhB was 600 mg g?1, which was about five times than that obtained on the unmodified biomass. Dye loaded modified biomass was regenerated by (1) a common eluent: HNO3 solution and (2) a self‐cleaning eluent: TiO2 hydrosol, while the pH of both systems varied from 1 to 4. Desorption experimental results showed that low desorption rates were obtained in both systems after the first desorption cycle. A large volume of HNO3 solution was needed to obtain high desorption rate, and a concentrated solution of RhB was left, which brought a secondary pollution. As a self‐cleaning eluent, acid TiO2 hydrosol acted both as eluent and photocatalyst. The desorbed RhB could be photodegraded under sunlight irradiation and the same hydrosol could be used in the next desorption cycle without losing its activity, which could economize large volumes of solvent. The results showed an adsorption capacity of the regenerated biosorbent for RhB of 450 mg g?1 by using hydrosol with pH 2 as eluent after four desorption/photodegradation cycles.  相似文献   

3.
This work describes the modification of silica gel with dimethylglyoxime, in order to prepare an effective sorbent for the preconcentration and determination of copper. The sorption capacity of dimethylglyoxime‐modified silica‐gel (DMGMS) was 71.37 mg g–1 and the optimum pH for the quantitative recovery of copper was found to be 5.0. The optimum flow rate, sorbent amount, and sample volume were 1 mL min–1, 300 mg, and 50 mL, respectively. 10 mL of 0.1 mol L–1 HCl was the most suitable eluent. The detection limit of copper was 6.0 ng mL–1. The recommended method, for the determination of copper, is simple and reliable, without any notable matrix effect and can be successfully applied to environmental water samples. Copper recovery in the range from 99–100% was obtained from seawater and thermal spring water using this method. The method was applied to standard reference materials, NIST‐1515 (apple leaves) and NIST‐1643e (simulated fresh water), for the determination of copper and the results were in good agreement with certified values.  相似文献   

4.
One‐dimensional MoO3 nanofibers doped with Ce (MoO3 : CeO2) are synthesized by a method combining a sol‐gel process and an electrospinning technique. The resulting MoO3 : CeO2 is characterized by X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT‐IR) spectroscopy, and scanning electron microscopy (SEM). The catalytic degradation of rhodamine B and safranin‐T with MoO3 : CeO2 nanofiber catalyst is investigated in a continuous flowing mode using air (O2) as an oxidant. The results show that rhodamine B and safranin‐T are degraded effectively and the removal efficiencies are 98.3%, and 98.5%, respectively. In addition, the organic dyes are totally mineralized to simple inorganic species such as CO3–, Cl– and NO3–.  相似文献   

5.
A start‐up study for biohydrogen production from palm oil mill effluent (POME) is carried out in a pilot‐scale up‐flow anaerobic sludge blanket fixed‐film reactor (UASFF). A substrate with a chemical oxygen demand (COD) of 30 g L?1 is used, starting with molasses solution for 30 days and followed by a 10% v/v increment of POME/molasses ratio. At 100% POME, a hydrogen content of 80%, hydrogen production rate of 36 L H2 per day, and maximum COD removal of 48.7% are achieved. Bio‐kinetic coefficients of Monod, first‐order, Grau second‐order, and Stover‐Kincannon kinetic models are calculated to describe the performance of the system. The steady‐state data with 100% POME shows that Monod and Stover‐Kincannon models with bio‐kinetic coefficients of half‐velocity constant (Ks) of 6000 mg COD L?1, microbial decay rate (Kd) of 0.0015 per day, growth yield constant (Y) of 0.786 mg volatile suspended solids (VSS)/mg COD, specific biomass growth rate (μmax) of 0.568 per day, and substrate consumption rate of (Umax) 3.98 g/L day could be considered as superior models with correlation coefficients (R2) of 0.918 and 0.989, respectively, compared to first‐order and Grau's second‐order models with coefficients of K1 1.08 per day, R2 0.739, and K2s 1.69 per day, a = 7.0 per day, b = 0.847.  相似文献   

6.
Hydrological regimes in the Yellow River have changed significantly because of climate change and intensive human interventions. These changes present severe challenges to water resource utilization and ecological development. Variation of run‐off, suspended sediment load (SSL), and eight precipitation indices (P1: 0–12 mm·day?1, P12: 12–25 mm·day?1, P25: 25–50 mm·day?1, P50: P ≥ 50 mm·day?1 and corresponding rainfall day: Pd1, Pd12, Pd25, Pd50 day year?1) in three critical parts of the Yellow River basin (source region: SRYRB, upper reaches: URYRB, middle reaches: MRYRB) were investigated for the period from 1960 to 2015. The results show that run‐off and SSL significantly decreased (P < 0.01) in the URYRB and the MRYRB, whereas their decline in the SRYRB was insignificant (P > 0.05). Moreover, run‐off in the URYRB had one change point in 1987, and SSL in the URYRB as well as run‐off and SSL in the MRYRB had two change points (in the 1970s and the 1990s). Over the same period, only Pd1 and Pd12 in the SRYRB showed significant increasing trends, and an abrupt change appeared in 1981. The optimal precipitation indices for assessing the effects of precipitation on run‐off and SSL in the URYRB and MRYRB were Pd50 and P12, respectively. A double‐mass curve analysis showed that precipitation and human activities contributed to approximately 20% and 80% of the reduction in run‐off, respectively, for both the SRYRB and the MRYRB. However, the contribution rate of precipitation and human activities on SSL reduction was approximately 40% and 60% in the URYRB and 5% and 95% in the MRYRB, respectively. Human activities, primarily soil and water conservation measures and water extraction (diversion), were the main factors (>50%) that reduced the run‐off. However, the dominant driving factors for SSL reduction were soil and water conservation measures and reservoir interception, for which the contribution rate was higher than 70% in the MRYRB. This work strengthens the understanding of hydrological responses to precipitation change and provides a useful reference for regional water resource utilization.  相似文献   

7.
Effects of short‐term (1 h exposure) and long‐term (7 d exposure) aluminium stress on photosynthesis and reproductive capacity have been studied in Euglena gracilis strain Z. Following concentrations of Altot (added as AlCl3) were tested: 0.5 mg L‐1, 1.0 mg L‐1, 1.5 mg L‐1, 2.5 mg L‐1, 5.0 mg L‐1, 7.5 mg L‐1, 10.0 mg L‐1, and 15.0 mg L‐1 Al, respectively. Growth rates at different aluminium concentrations did not show significant differences, except at 15.0 mg L‐1Al. Initial respiration was higher in long‐term than in the short‐term experiments. It is supposed that an energy‐dependent mechanism of excretion of aluminium ions has been active in the stressed cells. Consequently, the cells of E. gracilis after long‐term exposure to aluminium are believed to be more acclimatised to the aluminium stress. Photosynthetic efficiency (PE) has been negatively affected by aluminium in all experiments performed. Differences between control algae and those treated with aluminium were significant in all cases. PE in long‐term experiments was in general significantly higher at all concentrations of aluminium studied, compared to the short‐term experiments. The aluminium concentrations tested led only to a general decrease in PE while the level of decrease was not especially concentration‐dependent. In general, aluminium tolerance of E. gracilis can be estimated as low, especially by short‐term exposure. However, good acclimatisation capacity of this green flagellate to aluminium doses by long‐term exposure can be supposed.  相似文献   

8.
Dust deposition onto mountain snow cover in the Upper Colorado River Basin frequently occurs in the spring when wind speeds and dust emission peaks on the nearby Colorado Plateau. Dust loading has increased since the intensive settlement in the western USA in the mid 1880s. The effects of dust‐on‐snow have been well studied at Senator Beck Basin Study Area (SBBSA) in the San Juan Mountains, CO, the first high‐altitude area of contact for predominantly southwesterly winds transporting dust from the southern Colorado Plateau. To capture variability in dust transport from the broader Colorado Plateau and dust deposition across a larger area of the Colorado River water sources, an additional study plot was established in 2009 on Grand Mesa, 150 km to the north of SBBSA in west central, CO. Here, we compare the 4‐year (2010–2013) dust source, deposition, and radiative forcing records at Grand Mesa Study Plot (GMSP) and Swamp Angel Study Plot (SASP), SBBSA's subalpine study plot. The study plots have similar site elevations/environments and differ mainly in the amount of dust deposited and ensuing impacts. At SASP, end of year dust concentrations ranged from 0.83 mg g?1 to 4.80 mg g?1, and daily mean spring dust radiative forcing ranged from 50–65 W m?2, advancing melt by 24–49 days. At GMSP, which received 1.0 mg g?1 less dust per season on average, spring radiative forcings of 32–50 W m?2 advanced melt by 15–30 days. Remote sensing imagery showed that observed dust events were frequently associated with dust emission from the southern Colorado Plateau. Dust from these sources generally passed south of GMSP, and back trajectory footprints modelled for observed dust events were commonly more westerly and northerly for GMSP relative to SASP. These factors suggest that although the southern Colorado Plateau contains important dust sources, dust contributions from other dust sources contribute to dust loading in this region, and likely account for the majority of dust loading at GMSP. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

9.
Performance‐based engineering (PBE) methodologies allow for the design of more reliable earthquake‐resistant structures. Nonetheless, to implement PBE techniques, accurate finite element models of critical components are needed. With these objectives in mind, initially, we describe an experimental study on the seismic behaviour of both beam‐to‐column (BTC) and column‐base (CB) joints made of high‐strength steel S590 circular columns filled with concrete. These joints belonged to moment‐resisting frames (MRFs) that constituted the lateral‐force‐resisting system of an office building. BTC joints were conceived as rigid and of partial strength, whereas CB joints were designed as rigid and of full strength. Tests on a BTC joint composed of an S275 steel composite beam and high‐strength steel concrete‐filled tubes were carried out. Moreover, two seismic CB joints were tested with stiffeners welded to the base plate and anchor bolts embedded in the concrete foundation as well as where part of a column was embedded in the foundation with no stiffeners. A test programme was carried out with the aim of characterising these joints under monotonic, cyclic and random loads. Experimental results are presented by means of both force–interstory drift ratio and moment–rotation relationships. The outcomes demonstrated the adequacy of these joints to be used for MRFs of medium ductility class located in zones of moderate seismic hazard. Then, a numerical calibration of the whole joint subassemblies was successfully accomplished. Finally, non‐linear time‐history analyses performed on 2D MRFs provided useful information on the seismic behaviour of relevant MRFs. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

10.
The present work investigated the biosorption of nickel from synthetic and electroplating industrial effluents using a green marine algae Ulva reticulata. Preliminary batch results imply that pH 4.5 was optimum for nickel uptake and the isotherm experiments conducted at this pH condition indicated that U. reticulata can biosorb 62.3 mg g–1 nickel ions from synthetic solutions, according to the Langmuir model. Desorption was effective and practical using 0.1 M CaCl2 (pH 2.5, HCl) and the biomass was regenerated and reused for three cycles. Continuous biosorption experiments were performed in an upflow packed column (2 cm I.D and 35 cm height). Among the two electroplating effluents used, effluent‐1 is characterized by excess co‐ions and high nickel ion content. This influenced the column nickel uptake with U. reticulata exhibiting 52.1 mg g–1 in the case of effluent‐1 compared to 56.5 mg g–1 in the case of synthetic solution. On the other hand U. reticulata performed well in effluent‐2 with uptakes of 53.3 and 54.3 mg g–1 for effluent‐2 and synthetic solution, respectively. Mathematical modeling of column experimental data was performed using nonlinear forms of the Thomas‐ and modified dose‐response models, with the latter able to simulate breakthrough curves with high correlation coefficients.  相似文献   

11.
Polyhydroxyalkanoates (PHAs), environmental friendly polyesters, can be produced by a wide range of microorganisms in nutrient‐limiting conditions. In the present study a new bacterial strain, able to produce high quantities of poly‐3‐hydroxybutyrate (PHB), is isolated from contaminated soil. The isolate is characterized and identified as Bacillus cereus Y23, based on morphological, physiological characteristics, and 16S ribosomal RNA gene sequences. PHB production is evaluated using different carbon and nitrogen sources and nutritional and culture conditions are optimized. The highest PHB production of 5.12 g L?1 was obtained in growth medium containing fructose and ammonium sulfate at a C/N ratio of 30, 0.3% yeast extract, 4.5 g L?1 phosphate solution, pH 7, inoculum size of 0.3%, and agitation rate of 150 rpm after 48 h of incubation at 32 °C. The PHB production decrement can be attributed to the intracellular utilization of the polymer during the stationary phase of the cellular growth and to the sporulation process. The presence of the main functional groups of PHB polymer is verified by Fourier‐transform infrared analysis. At optimum conditions, B. cereus Y23 turned out to be a good candidate for industrial production of PHB since it accumulates up to 67.9% of its dry weight.  相似文献   

12.
The demand for clean water is on the increase as the population increases. One of the ways to address the water shortage is to treat the polluted water through removal of the contaminants. The use of adsorbents for pollutant removal is one of the promising methods. Seaweed is an aquatic plant and its sorption ability for selected metals in water was investigated in this study. We report the performance of the seaweed (Caulerpa serrulata) before and after modification with ethylenediamine (EDA), on adsorption of copper, lead and cadmium in aqueous solution. The adsorption capacities for Cu, Cd and Pb were 5.27 mg g−1, 2.12 mg g−1 and 2.16 mg g−1, respectively, with the EDA-modified seaweed, and 3.29 mg g−1, 4.57 mg g−1 and 1.06 mg g−1, with the unmodified weed, respectively. The pH for maximum adsorption was found to be within the range of pH 4–pH 6. In a separate investigation, it was found that 0.1 g of dried seaweed leached 20 mg of dissolved organic carbon (DOC) using 100 ml of distilled-deionised water. The resulting solution was green. The leaching phenomenon contributes to secondary pollution. Modification of the seaweed with EDA reduced the DOC content by half (50%) and also removed the green colouration. Kinetic studies showed that the adsorbent was able to take up to 95% of the metals (in synthetic standard solutions) in less than 10 min. The adsorbed metals were then stripped using a solution of 0.5 M HNO3 indicating that the adsorbent can be regenerated. In addition, the study revealed that modification improved the thermal stability of the adsorbent such that even when the temperature was raised to 1000 °C, more than 80% (compared to <50% for unmodified weed) of the modified adsorbent was not degraded, indicating that modification had a significant influence on the thermal stability of seaweed. The modified seaweed has been shown to have great potential for the removal of metals and DOC in polluted water. The modified adsorbent can therefore be applied for the removal of metals in polluted waters hence suitable for treatment of water for domestic consumption at a point of use.  相似文献   

13.
Dust, as a source of trace metal elements, affects the health of society. The spatial and temporal concentrations of dust‐bound trace metals (Cd, Pb, Ni, Zn, Cu, and Mn) in Kuhdasht watershed (456 km2), Lorestan Province, Iran, is investigated. Dust is collected using glass traps placed in ten research stations in the region. The spatial and temporal distribution of dust trace metals are plotted using ARC‐GIS. The highest and the lowest concentrations of Zn (9751150 mg kg?1), Pb (46.352.9 mg kg?1), and Cd (2.443.30 mg kg?1) are obtained in winter, of Ni (98110 mg kg?1) and Cu in autumn (16.053.5 mg kg?1), and of Mn in summer (385505 mg kg?1). The spatial concentrations of dust‐bound trace metals indicate all, except Cu, show a decreasing trend from the mountains toward the plains, similar to that of soil and of dust, except for Zn, which shows higher concentrations in dust than in soil. The potential sources of dust‐bound trace metals and their rate of contamination are also investigated using the enrichment and contamination factors. The major sources of Cd and Zn in the dust of watershed are due to anthropogenic activities or from activities outside the borders.  相似文献   

14.
The removal of Malachite green (MG) from aqueous solutions by cross‐linked chitosan coated bentonite (CCB) beads was investigated and the CCB beads were characterized by Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) and X‐ray diffraction (XRD) analysis. Solubility and swelling tests were performed in order to determine the stability of the CCB beads in acidic solution, basic solution and distilled water. The amount of MG adsorbed was shown to be influenced by the initial pH of the solution, contact time and the initial MG concentration. A kinetic study indicated that a pseudo‐second‐order model agreed well with the experimental data. From the Langmuir isotherm model, the maximum adsorption capacity of MG was found to be 435.0 mg g–1. Desorption tests were carried out at different concentrations of EDTA, H2SO4 and NaOH. However, all desorbing solutions showed zero recovery of MG at all concentrations.  相似文献   

15.
The Hakusan volcano, central Japan, is located in a region where two subducting plates (the Pacific Plate and the Philippine Sea Plate) overlap near the junction of four plates adjacent to the Japanese Islands (the Pacific Plate, the Philippine Sea Plate, the Eurasia Plate, and the North American Plate). The Hakusan volcano consists of products from four major volcanic episodes: Kagamuro, Ko‐hakusan, and Shin‐Hakusan I and II. To date the eruption events of the Hakusan volcano we applied thermoluminescence and fission track methods. 238U(234U)–230Th disequilibrium and 206Pb/238U methods were applied to date the zircon crystallization ages for estimating the magma residence time before the eruptions. The eruption ages we obtained are ca 250 ka for Kagamuro, ca 100 ka and ca 60 ka for Ko‐Hakusan, ca 50 ka for Shin‐Hakusan I, and <10 ka for Shin‐Hakusan II. They are concordant with previous reports based on K–Ar dating. Some of the pyroclastic rocks, possibly originating from Shin‐Hakusan II activities, are dated to be ca 36 ka or 50 ka, and belong to the Shin‐Hakusan I activity. The zircon crystallization ages show several clusters prior to eruption. The magma residence time was estimated for each volcanic activity by comparing the major crystallization events and eruption ages, and we found a gradual decrease from ca. 500 ky for the Kagamuro activity to ca. 5 ky for the Shin‐Hakusan II activity. This decrease in residence time may be responsible for the decrease in volume of erupted material estimated from the current topography of the region. The scale of volcanic activity, which was deduced from the number of crystallized zircons, is more or less constant throughout the Hakusan volcanic activity. Therefore, the decrease in magma residence time is most likely the result of stress field change.  相似文献   

16.
ZVI‐Clay is an emerging remediation approach that combines zero‐valent iron (ZVI)‐mediated degradation and in situ stabilization of chlorinated solvents. Through use of in situ soil mixing to deliver reagents, reagent‐contaminant contact issues associated with natural subsurface heterogeneity are overcome. This article describes implementation, treatment performance, and reaction kinetics during the first year after application of the ZVI‐Clay remediation approach at Marine Corps Base Camp Lejeune, North Carolina. Primary contaminants included trichloroethylene, 1,1,2,2‐tetrachloroethane, and related natural degradation products. For the field application, 22,900 m3 of soils were treated to an average depth of 7.6 m with 2% ZVI and 3% sodium bentonite (dry weight basis). Performance monitoring included analysis of soil and water samples. After 1 year, total concentrations of chlorinated volatile organic compounds (CVOCs) in soil samples were decreased by site‐wide average and median values of 97% and >99%, respectively. Total CVOC concentrations in groundwater were reduced by average and median values of 81% and >99%, respectively. In several of the soil and groundwater monitoring locations, reductions in total CVOC concentrations of greater than 99.9% were apparent. Further reduction in concentrations of chlorinated solvents is expected with time. Pre‐ and post‐mixing average hydraulic conductivity values were 1.7 × 10?5 and 5.2 × 10?8 m/s, respectively, indicating a reduction of about 2.5 orders of magnitude. By achieving simultaneous contaminant mass depletion and hydraulic conductivity reduction, contaminant flux reductions of several orders of magnitude are predicted.  相似文献   

17.
This paper investigates the impact of a 1000‐year flood in August 2002 on floodplains and valley morphology of an Austrian mixed alluvial bed rock river. Discharges with a recurrence interval between 500 and 2000 years caused distinctive overbank scouring and material deposition in the floodplains. After the 1000‐year flood, those morphologically affected areas were at random intervals documented over the whole longitudinal profile. In addition to overbank erosion in curved sections (cut‐offs), the river bed locally widened, floodplain stripping occurred and local overbank scours were documented along straight parts of the river. A hydrodynamic‐numerical model, combined with field measurements, was used to analyse the cause of these erosional landforms. Based on the modelled hydraulic conditions for a one‐year flood (30–78 m3 s–1) and the catastrophic 2002 event (700–800 m3 s–1), the numerical results allowed a cause‐effect study with 19 parameters. Deterministic and statistical analysis (ANOVA, discriminant analysis) showed that the morphodynamic effects of the 2002 flood were influenced by the variability of valley morphology of the Kamp River, which led partially to supercritical flow during flood constriction. These processes were in some cases also anthropogenically influenced. Lateral constriction and expansion of the valley geometry over short distances led to scouring and aggradation within the inundated areas during the event. These morphological features were therefore responsible for the elongated scour holes in the floodplains. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

18.
《Marine pollution bulletin》2013,76(1-2):133-139
Effective control of outbreaks of Acanthaster planci represents the most immediate and practical intervention to reverse sustained declines in coral cover on reefs in the Indo-Pacific. This study explored the minimum doses of oxbile, oxgall, and thiosulfate-citrate-bile-sucrose agar (TCBS) that result in reliable and comprehensive mortality when injected into adult A. planci. The minimum doses required to induce 100% mortality among starfish (n = 10) were 4 g l−1 of oxbile, 8 g l−1 of oxgall and 22 g l−1 of TCBS. Moreover, there was no evidence of unintended side effects for other coral reef organisms (e.g., scleractinian corals, echinoderms and fishes) when using oxbile, oxgall, or TCBS at minimum doses. The effectiveness of peptones in killing crown-of-thorns starfish was also tested, but inconsistency in the results revealed that these proteins are unreliable.  相似文献   

19.
Dissolved organic matter (DOM) quality and quantity is not measured routinely in‐situ limiting our ability to quantify DOM process dynamics. This is problematic given legislative obligations to determine event based variability; however, recent advances in field deployable optical sensing technology provide the opportunity to address this problem. In this paper, we outline a new approach for in‐situ quantification of DOM quantity (Dissolved Organic Carbon: DOC) and a component of quality (Biochemical Oxygen Demand: BOD) using a multi‐wavelength, through‐flow fluorescence sensor. The sensor measured tryptophan‐like (Peak T) and humic‐like (Peak C) fluorescence, alongside water temperature and turbidity. Laboratory derived coefficients were developed to compensate for thermal quenching and turbidity interference (i.e., light attenuation and scattering). Field tests were undertaken on an urban river with ageing wastewater and stormwater infrastructure (Bourn Brook; Birmingham, UK). Sensor output was validated against laboratory determinations of DOC and BOD collected by discrete grab sampling during baseflow and stormflow conditions. Data driven regression models were then compared to laboratory correction methods. A combination of temperature and turbidity compensated Peak T and Peak C was found to be a good predictor of DOC concentration (R2 = 0.92). Conversely, using temperature and turbidity correction coefficients provided low predictive power for BOD (R2 = 0.46 and R2 = 0.51, for Peak C and T, respectively). For this study system, turbidity appeared to be a reasonable proxy for BOD, R2 = 0.86. However, a linear mixed effect model with temperature compensated Peak T and turbidity provided a robust BOD prediction (R2 = 0.95). These findings indicate that with careful initial calibration, multi‐wavelength fluorescence, coupled with turbidity, and temperature provides a feasible proxy for continuous, in‐situ measurement of DOC concentration and BOD. This approach represents a cost effective monitoring solution, particularly when compared to UV – absorbance sensors and DOC analysers, and could be readily adopted for research and industrial applications.  相似文献   

20.
Highly toxic divalent cadmium causes serious environmental issues. To quickly monitor and/or efficiently remove this potentially toxic metal ion as well as to explore its interfacial chemistry with metal oxides, a sulfur and carbon co‐doped titania (S/C‐TiO2) composite is synthesized via a facile sol‐gel method with the assistance of sodium lignosulphonate (SLS). The prepared composite displays a well‐crystallized TiO2 nanostructure comprising the anatase phase. Both S and C, which are derived from the SLS template, are found to enter the TiO2 lattice. The S/C‐TiO2 composite exhibits a porous structure with a wide pore size distribution. The newly synthesized composite shows adsorption capability for the potentially toxic metal Cd(II). The adsorption process requires <5 min to reach equilibrium. The measured equilibrium adsorption capacity is 19.42 mg g?1, which is twice as high as that of bare TiO2. The removal efficiency is as high as 97%. Moreover, the materials are suitable for contaminated solutions over a wide range of pH values and various initial cadmium concentrations. A mechanism for the enhanced adsorption behavior is also proposed.  相似文献   

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