- Dendrocalamus strictus Charcoal: An Efficient Adsorbent for Removal of Cu (II) Ions from Aqueous Solution and its Applicability in the Reduction of Genotoxic Potential of Cu (II) Ions. [Journal Article]
- WEWater Environ Res 2018 Nov 01; 90(11):1964-1976
- The present study pertains to evaluate the efficiency of Dendrocalamus strictus charcoal powder as an adsorbent to adsorb copper ions from aqueous solution under different conditions of pH, initial...
The present study pertains to evaluate the efficiency of Dendrocalamus strictus charcoal powder as an adsorbent to adsorb copper ions from aqueous solution under different conditions of pH, initial metal ion concentration, adsorbent dose, contact time, and temperature. Physical characterization of Dendrocalamus strictus charcoal powder was performed using different techniques such as scanning electron microscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy, Brunauer Emmett and Teller surface analysis and X-ray diffraction. Langmuir, Freundlich, and Temkin isotherm models were employed to describe the adsorption behavior of adsorbent in the removal of copper ions from aqueous solution. Thermodynamic parameters indicated that the adsorption of copper ions onto the surface of the adsorbent was feasible, spontaneous, and endothermic in nature. Data analysis using kinetic models revealed the pseudo-second-order as the suitable model to describe the process of adsorption. Studies were further carried out to analyze the genotoxic effects of copper ions in aqueous solution before and after adsorption, using Allium cepa assay. This study revealed that Dendrocalamus strictus charcoal powder could be applied as an alternative for more costly adsorbents in the detoxification of copper ions from aqueous solution.
- N-methylcarbamate pesticides and their phenolic degradation products: hydrolytic decay, sequestration and metal complexation studies. [Journal Article]
- JEJ Environ Sci Health B 2018 Nov 21; :1-7
- We report on the rates of decomposition of a group of N-methylcarbamate (NMC) pesticides (carbaryl, carbofuran and propoxur) under pre-determined tropical field conditions. Rates of decomposition for...
We report on the rates of decomposition of a group of N-methylcarbamate (NMC) pesticides (carbaryl, carbofuran and propoxur) under pre-determined tropical field conditions. Rates of decomposition for three NMCs were determined at pH 7.08 and T = 20 °C and pH 7.70 and T = 33 °C respectively, as follows: carbaryl (78 days and 69 days); carbofuran (143 days and 83 days) and propoxur (116 days and 79 days). Investigation on methods for removal of NMCs and their phenolic decomposition products shows that activated charcoal outperforms zeolite, alumina, diatomaceous earth, cellulose and montmorillonite clay in the removal of both NMCs and phenols from aqueous solution. Furthermore, metal complexation studies on the NMCs and phenols showed that Fe (III) forms a complex with isopropoxyphenol (IPP) within which the Fe:IPP ratio is 1:3, indicative of the formation of a metal chelate complex with the formula Fe(IPP)3.
- Partitioning biochar properties to elucidate their contributions to bacterial and fungal community composition of purple soil. [Journal Article]
- STSci Total Environ 2019 Jan 15; 648:1333-1341
- Although effects of biochar application on soil microorganism have been increasingly reported, the direct evidences for demonstrating the contributions of biochar chemical and physical properties to ...
Although effects of biochar application on soil microorganism have been increasingly reported, the direct evidences for demonstrating the contributions of biochar chemical and physical properties to soil microorganisms are still lacking. Herein, we partitioned corn-straw biochar (BC) into three fractions, including aqueous extractable substances (AE), organic extractable substances (OE) and the remaining solid (EBC) after these two extractions. These fractions and BC were added to purple soil for a 30-day incubation. Soil properties, microbial α-diversity indices and microbial community compositions were analysed after the incubation. The results showed the obvious changes in soil properties, along with higher available P, available K and total organic C, as well as, lower pH and available N than those of soil without biochar, were observed in the BC-treated soil. Illumina Miseq sequencing displayed a distinct difference between responses of bacteria and fungi to biochar application, in which fungal richness and diversity were increased, and no significant changes happened in bacterial richness. Furthermore, biochar had apparent effects on bacterial and fungal community compositions at phylum level, which were most close to the influences of AE and EBC, respectively. These results suggested that AE, improving soil nutrients (e.g., total N), played a pivotal role in changing bacterial phylum community composition. The EBC, regarded as physical structure and relatively recalcitrant compounds of BC, had a dominant contribution to the influence of biochar on the fungal community composition.
- Statistical optimization of preparing marine macroalgae derived activated carbon/iron oxide magnetic composites for sequestering acetylsalicylic acid from aqueous media using response surface methodologys. [Journal Article]
- CChemosphere 2019; 215:432-443
- This study focuses on the optimization of synthetic conditions for preparing marine macroalgae-derived activated carbon/iron oxide magnetic composites (AC/Fe-MC) and its feasibility for the removal o...
This study focuses on the optimization of synthetic conditions for preparing marine macroalgae-derived activated carbon/iron oxide magnetic composites (AC/Fe-MC) and its feasibility for the removal of acetylsalicylic acid from aqueous media. Response surface methodology coupled with a 3k Box-Behnken design was applied to determine the optimal conditions (independent variables: impregnation ratio, activation temperature, and activation time) towards two response variables (production yield and adsorption capacity). According to the analysis of variance and numerical desirability function approaches, the optimal conditions were impregnation ratio of 2.62:1, activation temperature of 727 °C, and activation time of 129 min. Physicochemical properties of the prepared composite revealed that AC/Fe-MC possesses a porous structure and superparamagnetic property, which substantially contributed to the effective adsorption capacity and separation from the solution using an external magnetic field. Adsorption kinetics and equilibrium studies delineated that the pseudo-second-order and Sips isotherm models represent the adsorption behavior of AC/Fe-MC accurately. The maximum adsorption capacity of AC/Fe-MC was found to be around 127 mg/g at 10 °C, as fitted by Sips isotherm model, which is higher than that of other adsorbents reported in the literature. Intraparticle diffusion and Boyd models suggested that the adsorption process was mainly controlled by film diffusion mechanism. Lastly, thermodynamic and isosteric heat of adsorption analyses demonstrated that the adsorption process was controlled by physisorption and exothermic mechanisms.
- Study of ciprofloxacin removal by biochar obtained from used tea leaves. [Journal Article]
- JEJ Environ Sci (China) 2018; 73:20-30
- In this study, used tea leaves (UTLs) were pyrolyzed to obtain used tea-leaf biochar (UTC), and then the UTC was used as an adsorbent to remove ciprofloxacin (CIP) from aqueous solutions. Batch exper...
In this study, used tea leaves (UTLs) were pyrolyzed to obtain used tea-leaf biochar (UTC), and then the UTC was used as an adsorbent to remove ciprofloxacin (CIP) from aqueous solutions. Batch experiments were conducted to investigate the CIP adsorption performance and mechanism. The results showed that the CIP-adsorbing ability first increased and then declined as the UTC pyrolysis temperature increased. The UTC obtained at 450°C presented excellent CIP-absorbing ability at pH6 and 40°C. The maximum monolayer adsorption capacity was 238.10mg/g based on the Langmuir isotherm model. The pseudo-second-order kinetic equation agreed well with the CIP adsorption process, which was controlled by both external boundary layer diffusion and intra-particle diffusion. The characterization analysis revealed that the OH groups, CC bonds of aromatic rings, CH groups in aromatic rings and phenolic CO bonds play vital roles in the CIP adsorption process, and that the NC, NO, OCO and COH groups of UTC were consumed in large quantities. π-π interactions, hydrogen bonding and electrostatic attraction are inferred as the main adsorption mechanisms. The present work provides not only a feasible and promising approach for UTLs utilization but also a potential adsorbent material for removing high concentrations of CIP from aqueous solutions.
- Alginate-modified biochar derived from Ca(II)-impregnated biomass: Excellent anti-interference ability for Pb(II) removal. [Journal Article]
- EEEcotoxicol Environ Saf 2018 Dec 15; 165:211-218
- A novel biochar modified with sodium alginate was prepared using Ca(II)-impregnated biomass, and used to remove metals from aqueous solutions. The maximum adsorption capacity for Pb(II) was estimated...
A novel biochar modified with sodium alginate was prepared using Ca(II)-impregnated biomass, and used to remove metals from aqueous solutions. The maximum adsorption capacity for Pb(II) was estimated to be 1.225 mmol/g (253.6 mg/g), which is far more than that of most adsorbents. Moreover, the modified biochar had a great anti-interference ability for effective removal of Pb(II) from multi-metal system. The biochar still had strong ability to adsorb Pb(II) when the initial concentrations of interfering ions were 5 times higher than that of Pb(II). Functional groups and minerals of the biochar worked for Pb(II) removal and the anti-interference ability. On the one hand, carboxyl could complex with Pb(II) through monodentate and bidentate bridging; on the other hand, Pb(II) was easier to form a precipitate with minerals than other metals. This study suggested that the novel biochar had the potential for practical application in effective removal of Pb(II) from wastewater.
- Efficacy of Sida pilosa Retz aqueous extract against Schistosoma mansoni - induced granulomatous inflammation in the liver and the intestine of mice: histomorphometry and gastrointestinal motility evaluation. [Journal Article]
- BCBMC Complement Altern Med 2018 Sep 06; 18(1):247
- CONCLUSIONS: Our findings provide evidence that SpAE improves granulomatous inflammation induced by S. mansoni both in the liver and in the intestine, as well as it re-establishes normal gastrointestinal transit. SpAE may be used for the development of alternative medicine against S. mansoni infection.
- Adsorption characteristics of vanadium on different resin-active carbon composite electrodes in capacitive deionization. [Journal Article]
- CChemosphere 2018; 212:34-40
- Three kinds of anion exchange resins (AERs) (D201, D301, D314) and one kind of cation exchange resin (D860) were used with activated carbon (AC) to fabricated the ion exchange resin-AC (IER/AC) compo...
Three kinds of anion exchange resins (AERs) (D201, D301, D314) and one kind of cation exchange resin (D860) were used with activated carbon (AC) to fabricated the ion exchange resin-AC (IER/AC) composite electrodes in capacitive deionization (CDI) for selective adsorption of V(V). The characteristics of four kinds of composite electrodes, such as wettability, pore distribution and electrochemical properties, indicates IER/AC composite has great potential as electrode materials for the electro-adsorption in CDI. The pH of solution has apparent influence on the adsorption capacity of the composite electrodes for V(V) because of the various V(V) species in the solution with different pH. The reduction rate of V(V) on IER/AC electrodes mainly relates to the amount of VO2+ in solution. The adsorption capacity of AER/AC electrodes for V(V) is slightly affected by the applied voltage may be due to that the adsorption of V(V) is mainly dependent on ion exchange with AERs and only a minority of V(V) is adsorbed by electrostatic adsorption. The adsorbed V(V) on D860/AC electrode decreases with the rising applied voltage because the pH increases with the increase of voltage. The separation of V(V) from V(V), Al and P indicates that the selective adsorption capability of IER/AC composite electrode is related to the migration rate of V(V), Al, P at different voltages and the selectivity of resins. This study may provide reference for recovering and separating metal ions from aqueous solution with CDI.
- Research on the sustainable efficacy of g-MoS2 decorated biochar nanocomposites for removing tetracycline hydrochloride from antibiotic-polluted aqueous solution. [Journal Article]
- STSci Total Environ 2019 Jan 15; 648:206-217
- Antibiotic concentrations in surface waters far exceed the pollution limit due to the abuse of pharmaceuticals, resulting in an urgent need for an approach with potential efficiency, sustainability a...
Antibiotic concentrations in surface waters far exceed the pollution limit due to the abuse of pharmaceuticals, resulting in an urgent need for an approach with potential efficiency, sustainability and eco-friendliness to remove antibiotic pollutants. A novel biochar-based nanomaterial was synthesized by hydrothermal synthesis and was investigated for its removal potential for tetracycline hydrochloride (TC) from both artificial and real wastewater. The associative facilitation between biochar and g-MoS2 nanosheets was proposed, revealing the favorable surface structures and adsorption properties of the composite. The related adsorption kinetics, isotherms and thermodynamics were studied by several models with adsorption experimental data, turning out that biochar decorated by g-MoS2 exhibited optimum TC removal with adsorption capacity up to 249.45 mg/g at 298 K. The adsorption behavior of TC molecules on g-MoS2-BC can be interpreted well by three-step process, and it is dominated by several mechanisms containing pore-filling, electrostatic force, hydrogen bond and π-π interaction. In addition, the cost-effective g-MoS2-BC nanocomposites demonstrated excellent adsorption and recycling performance in TC-contaminated river water, which might provide the underlying insights needed to guide the design of promising approach for contaminant removal on a large scale in practical application.
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- Enhanced removal of phosphate from aqueous solutions using a modified sludge derived biochar: Comparative study of various modifying cations and RSM based optimization of pyrolysis parameters. [Journal Article]
- JEJ Environ Manage 2018 Nov 01; 225:75-83
- Different biochars produced by the impregnation of Mg, Ca, Al, Cu, and Fe were compared for the phosphate (P) uptake capacity and the effect on solution pH. Among them, Ca- and Mg-rich biochars demon...
Different biochars produced by the impregnation of Mg, Ca, Al, Cu, and Fe were compared for the phosphate (P) uptake capacity and the effect on solution pH. Among them, Ca- and Mg-rich biochars demonstrate better sorption ability to P and have less effect on pH change. The optimum conditions of the pyrolysis processes were determined using response surface methodology. Comparison of the P removal efficiency of these two biochars under optimum conditions imply the superior adsorption capability of Ca-rich biochar. According to XRD analysis, calcite is the dominant mineral on the biochar surface, indicating the potential of Ca-rich biochar for P removal by adsorption and precipitation. Predictive second-order kinetic and linear Langmuir isotherm models could adequately interpret the P sorption process for optimized Ca-rich biochar. The maximum P sorption capacity of Ca-rich biochar of 153.85 mg/g is superior to other adsorbents reported in literature.