The Experts below are selected from a list of 8490 Experts worldwide ranked by ideXlab platform

Takeshi Matsuura - One of the best experts on this subject based on the ideXlab platform.

  • polysulfone hydrous Ferric Oxide ultrafiltration mixed matrix membrane preparation characterization and its adsorptive removal of lead ii from aqueous solution
    Chemical Engineering Journal, 2016
    Co-Authors: Norfazliana Abdullah, Jaafar Juhana, Rasoul Jamshidi Gohari, Norhaniza Yusof, Ahmad Fauzi Ismail, Woei Jye Lau, Takeshi Matsuura
    Abstract:

    Abstract In this work, polysulfone (PSf)/hydrous Ferric Oxide nanoparticles (HFO NPs) ultrafiltration mixed matrix membranes (MMMs) were prepared for adsorptive removal of lead (Pb) (II) from aqueous solution. The morphologies and physiochemical properties of prepared HFO NPs and MMMs were characterized using TEM, BET, XRD, FTIR, SEM, AFM, pure water flux analysis, contact angle measurement and membrane porosity analysis. The results revealed that the self-synthesized HFO NPs possessed a specific surface area (SSA) of 233.49 m 2 /g. Increasing weight ratio of HFO NPs in PSf membranes significantly enhanced membrane pure water flux from 229.5 L/m 2  h to 942.1 L/m 2  h, attributed by the improved membrane hydrophilicity (contact angle 8.0°) coupled with greater surface roughness (74.8 nm) and overall porosity (88.8%). Adsorption study showed that removal of Pb(II) was strongly dependent on pH in which the optimum pH was 6.5–7.0. Membrane M-1.5 (mass ratio of 1.5 HFO NPs:PSf) possessed the highest adsorption capacity of Pb(II) which was 13.2 mg/g. The adsorption mechanism of Pb(II) onto PSf/HFO MMMs was best fitted to Langmuir isotherm whereas the kinetic mechanism was best described by pseudo-second order model. The UF filtration study showed that this adsorptive MMMs produced permeate of high quality with Pb(II) content (

  • polysulfone hydrous Ferric Oxide ultrafiltration mixed matrix membrane preparation characterization and its adsorptive removal of lead ii from aqueous solution
    Chemical Engineering Journal, 2016
    Co-Authors: Norfazliana Abdullah, Jaafar Juhana, Rasoul Jamshidi Gohari, Norhaniza Yusof, Ahmad Fauzi Ismail, Takeshi Matsuura
    Abstract:

    Abstract In this work, polysulfone (PSf)/hydrous Ferric Oxide nanoparticles (HFO NPs) ultrafiltration mixed matrix membranes (MMMs) were prepared for adsorptive removal of lead (Pb) (II) from aqueous solution. The morphologies and physiochemical properties of prepared HFO NPs and MMMs were characterized using TEM, BET, XRD, FTIR, SEM, AFM, pure water flux analysis, contact angle measurement and membrane porosity analysis. The results revealed that the self-synthesized HFO NPs possessed a specific surface area (SSA) of 233.49 m 2 /g. Increasing weight ratio of HFO NPs in PSf membranes significantly enhanced membrane pure water flux from 229.5 L/m 2  h to 942.1 L/m 2  h, attributed by the improved membrane hydrophilicity (contact angle 8.0°) coupled with greater surface roughness (74.8 nm) and overall porosity (88.8%). Adsorption study showed that removal of Pb(II) was strongly dependent on pH in which the optimum pH was 6.5–7.0. Membrane M-1.5 (mass ratio of 1.5 HFO NPs:PSf) possessed the highest adsorption capacity of Pb(II) which was 13.2 mg/g. The adsorption mechanism of Pb(II) onto PSf/HFO MMMs was best fitted to Langmuir isotherm whereas the kinetic mechanism was best described by pseudo-second order model. The UF filtration study showed that this adsorptive MMMs produced permeate of high quality with Pb(II) content (

Bingcai Pan - One of the best experts on this subject based on the ideXlab platform.

  • simultaneous removal of as v and cr vi from water by macroporous anion exchanger supported nanoscale hydrous Ferric Oxide composite
    Chemosphere, 2017
    Co-Authors: Ming Hua, Chao Shan, Weiming Zhang, Bowen Yang, Bingcai Pan
    Abstract:

    As(V) and Cr(VI) are both highly toxic anionic pollutants and commonly co-exist in some industrial effluents and contaminated waters. In this study, simultaneous removal of them was efficiently achieved by employing a composite adsorbent (HFO-201) fabricated by immobilizing nanoscale hydrous Ferric Oxide (HFO) within a macroporous anion exchanger D201. The HFO-201 composite possesses two types of adsorption sites, i.e. the quaternary ammonium groups fixed on the D201 matrix and the embedded HFO nanoparticles. In the binary solution, the adsorption kinetic processes of both As(V) and Cr(VI) by HFO-201 were well fitted with the pseudo-first order kinetic model. Furthermore, HFO-201 exhibited a significantly higher adsorption capacity toward As(V) than D201 and an identical adsorption capacity toward Cr(VI) to D201. During the removal process, As(V) was captured by both the electrostatic attraction from the fixed quaternary ammonium groups and the formation of inner-sphere complex with the embedded HFO nanoparticles. Whereas, Cr(VI) was primarily adsorbed by the fixed ammonium groups. Fixed-bed treatment of As(V)/Cr(VI) binary synthetic water by HFO-201 resulted in elimination of As (from 1.0 to below 0.01 mg/L) and Cr (from 5.0 to below 0.05 mg/L), with the treatment capacity of 1700 bed volume (BV). Moreover, the exhausted HFO-201 was amenable to efficient in situ regeneration with a binary NaOH-NaCl solution for repeated use without any significant capacity loss.

  • arsenate adsorption by hydrous Ferric Oxide nanoparticles embedded in cross linked anion exchanger effect of the host pore structure
    ACS Applied Materials & Interfaces, 2016
    Co-Authors: Chao Shan, Yanyang Zhang, Weiming Zhang, Jianguo Cai, Bingcai Pan
    Abstract:

    Three composite adsorbents were fabricated via confined growth of hydrous Ferric Oxide (HFO) nanoparticles within cross-linked anion exchangers (NS) of different pore size distributions to investigate the effect of host pore structure on the adsorption of As(V). With the decrease in the average pore size of the NS hosts from 38.7 to 9.2 nm, the mean diameter of the confined HFO nanoparticles was lessened from 31.4 to 11.6 nm as observed by transmission electron microscopy (TEM), while the density of active surface sites was increased due to size-dependent effect proved by potentiometric titration. The adsorption capacity of As(V) yielded by Sips model was elevated from 24.2 to 31.6 mg/g via tailoring the pore size of the NS hosts, and the adsorption kinetics was slightly accelerated with the decrease of pore size in background solution containing 500 mg/L of Cl–. Furthermore, the enhanced adsorption of As(V) was achieved over a wide pH range from 3 to 10, as well as in the presence of competing anions inc...

  • modeling batch and column phosphate removal by hydrated Ferric Oxide based nanocomposite using response surface methodology and artificial neural network
    Chemical Engineering Journal, 2014
    Co-Authors: Yanyang Zhang, Bingcai Pan
    Abstract:

    Abstract Batch and column phosphate removal was conducted by a commercially available nano-hydrated Ferric Oxide composite HFO-201 under varying conditions, and the performance was modeled and predicted with the aid of artificial neural network (ANN) model and response surface methodology (RSM). Initial pH, sulfate concentration, operating temperature, and adsorbent dosage were chosen as four variables for the batch study, while the removal efficiency was considered as the output. A central composite design (CCD) was referred to design 33 sets of batch experiments, and a RSM model was developed to compare with the ANN model. The three-layer feed-forward back-propagation network was established in MATLAB to estimate the phosphate removal efficiency. The positive behavior of both models was verified by Pearson and Spearman coefficient and mean squared error (MSE). Analysis of variance (ANOVA) tests and sensitivity analysis were performed on the models to find relative influence of four variables. Temperature was deemed as the least influential whereas the other three variables were considered significant to the output. Genetic Algorithm (GA) was employed to find optimum dosages for a desired removal efficiency under given conditions. ANN modeling was further attempted to estimate the breakthrough curves of fixed-bed adsorption, where pH, sulfate, temperature, flow rate (BV/h) and bed volume was considered as variables. Predictions made by the developed models were in reasonably good agreement with the test runs. This study suggested that ANN and RSM be considered as effective tools to model and predict trace pollutants removal by nanocomposite adsorbents.

  • preparation of polymer supported hydrated Ferric Oxide based on donnan membrane effect and its application for arsenic removal
    Science China-chemistry, 2008
    Co-Authors: Qingjian Zhang, Bingcai Pan, Xinqing Chen, Weiming Zhang, Bingjun Pan, Quanxing Zhang, X S Zhao
    Abstract:

    In the present study a novel technique was proposed to prepare a polymer-supported hydrated Ferric Oxide (D201-HFO) based on Donnan membrane effect by using a strongly basic anion exchanger D201 as the host material and FeCl3-HCl-NaCl solution as the reaction environment. D201-HFO was found to exhibit higher capacity for arsenic removal than a commercial sorbent Purolite ArsenX. Furthermore, it presents favorable adsorption selectivity for arsenic removal from aqueous solution, as well as satisfactory kinetics. Fixed-bed column experiments showed that arsenic sorption on D201-HFO could result in concentration of this toxic metalloid element below 10 μg/L, which was the new maximum concentration limit set recently by the European Commission and imposed by the US EPA and China. Also, the spent D201-HFO is amenable to efficient regeneration by NaOH-NaCl solution.

Donald L. Sparks - One of the best experts on this subject based on the ideXlab platform.

  • ATR-FTIR spectroscopic studies of boric acid adsorption on hydrous Ferric Oxide
    Geochimica et Cosmochimica Acta, 2003
    Co-Authors: Derek Peak, George W Luther, Donald L. Sparks
    Abstract:

    Boron is an important micronutrient for plants, but high B levels in soils are often responsible for toxicity effects in plants. It is therefore important to understand reactions that may affect B availability in soils. In this study, Attenuated Total Reflectance Fourier transform Infrared (ATR-FTIR) spectroscopy was employed to investigate mechanisms of boric acid (B(OH)3) and borate (B(OH)4-) adsorption on hydrous Ferric Oxide (HFO). On the HFO surface, boric acid adsorbs via both physical adsorption (outer-sphere) and ligand exchange (inner-sphere) reactions. Both trigonal (boric acid) and tetrahedral (borate) boron are complexed on the HFO surface, and a mechanism where trigonal boric acid in solution reacts to form either trigonal or tetrahedral surface complexes is proposed based upon the spectroscopic results. The presence of outer-sphere boric acid complexes can be explained based on the Lewis acidity of the B metal center, and this complex has important implications for boron transport and availability. Outer-sphere boric acid is more likely to leach downward in soils in response to water flow. Outer-sphere boron would also be expected to be more available for plant uptake than more strongly bound boron complexes, and may more readily return to the soil solution when solution concentrations decrease. © 2003 Elsevier Science Ltd.

  • doi:10.1016/S0016-7037(03)00096-6 ATR-FTIR spectroscopic studies of boric acid adsorption on hydrous Ferric Oxide
    2002
    Co-Authors: Derek Peak, George W Luther, Donald L. Sparks
    Abstract:

    Abstract—Boron is an important micronutrient for plants, but high B levels in soils are often responsible for toxicity effects in plants. It is therefore important to understand reactions that may affect B availability in soils. In this study, Attenuated Total Reflectance Fourier transform Infrared (ATR-FTIR) spectroscopy was employed to investigate mechanisms of boric acid (B(OH)3) and borate (B(OH)4) adsorption on hydrous Ferric Oxide (HFO). On the HFO surface, boric acid adsorbs via both physical adsorption (outer-sphere) and ligand exchange (inner-sphere) reactions. Both trigonal (boric acid) and tetrahedral (borate) boron are complexed on the HFO surface, and a mechanism where trigonal boric acid in solution reacts to form either trigonal or tetrahedral surface complexes is proposed based upon the spectroscopic results. The presence of outer-sphere boric acid complexes can be explained based on the Lewis acidity of the B metal center, and this complex has important implications for boron transport and availability. Outer-sphere boric acid is more likely to leach downward in soils in response to water flow. Outer-sphere boron would also be expected to be more available for plant uptake than more strongly bound boron complexes, and may more readily return to the soil solution when solution concentrations decrease. Copyright © 2003 Elsevier Science Ltd 1

Tatsuya Atsumi - One of the best experts on this subject based on the ideXlab platform.

  • a case of osteomalacia due to deranged mineral balance caused by saccharated Ferric Oxide and short bowel syndrome a case report
    Medicine, 2017
    Co-Authors: Hiroshi Nomoto, So Nagai, Hideaki Miyoshi, Akinobu Nakamura, Naoyuki Kitao, Chikara Shimizu, Tatsuya Atsumi
    Abstract:

    Saccharated Ferric Oxide has been shown to lead to elevation of fibroblast growth factor 23, hypophosphatemia, and, consequently, osteomalacia. Moreover, mineral imbalance is often observed in patients with short-bowel syndrome to some degree.A 62-year-old woman with short-bowel syndrome related with multiple resections of small intestines due to Crohn disease received regular intravenous administration of saccharated Ferric Oxide. Over the course of treatment, she was diagnosed with tetany, which was attributed to hypocalcemia. Additional assessments of the patient revealed not only hypocalcemia, but also hypophosphatemia, hypomagnesemia, osteomalacia, and a high concentration of fibroblast growth factor 23 (314 pg/mL).We diagnosed her with mineral imbalance-induced osteomalacia due to saccharated Ferric Oxide and short-bowel syndrome.Magnesium replacement therapy and discontinuation of saccharated Ferric Oxide alone.These treatments were able to normalize her serum mineral levels and increase her bone mineral density.This case suggests that adequate evaluation of serum minerals, including phosphate and magnesium, during saccharated Ferric Oxide administration may be necessary, especially in patients with short-bowel syndrome.

Derek Peak - One of the best experts on this subject based on the ideXlab platform.

  • ATR-FTIR spectroscopic studies of boric acid adsorption on hydrous Ferric Oxide
    Geochimica et Cosmochimica Acta, 2003
    Co-Authors: Derek Peak, George W Luther, Donald L. Sparks
    Abstract:

    Boron is an important micronutrient for plants, but high B levels in soils are often responsible for toxicity effects in plants. It is therefore important to understand reactions that may affect B availability in soils. In this study, Attenuated Total Reflectance Fourier transform Infrared (ATR-FTIR) spectroscopy was employed to investigate mechanisms of boric acid (B(OH)3) and borate (B(OH)4-) adsorption on hydrous Ferric Oxide (HFO). On the HFO surface, boric acid adsorbs via both physical adsorption (outer-sphere) and ligand exchange (inner-sphere) reactions. Both trigonal (boric acid) and tetrahedral (borate) boron are complexed on the HFO surface, and a mechanism where trigonal boric acid in solution reacts to form either trigonal or tetrahedral surface complexes is proposed based upon the spectroscopic results. The presence of outer-sphere boric acid complexes can be explained based on the Lewis acidity of the B metal center, and this complex has important implications for boron transport and availability. Outer-sphere boric acid is more likely to leach downward in soils in response to water flow. Outer-sphere boron would also be expected to be more available for plant uptake than more strongly bound boron complexes, and may more readily return to the soil solution when solution concentrations decrease. © 2003 Elsevier Science Ltd.

  • doi:10.1016/S0016-7037(03)00096-6 ATR-FTIR spectroscopic studies of boric acid adsorption on hydrous Ferric Oxide
    2002
    Co-Authors: Derek Peak, George W Luther, Donald L. Sparks
    Abstract:

    Abstract—Boron is an important micronutrient for plants, but high B levels in soils are often responsible for toxicity effects in plants. It is therefore important to understand reactions that may affect B availability in soils. In this study, Attenuated Total Reflectance Fourier transform Infrared (ATR-FTIR) spectroscopy was employed to investigate mechanisms of boric acid (B(OH)3) and borate (B(OH)4) adsorption on hydrous Ferric Oxide (HFO). On the HFO surface, boric acid adsorbs via both physical adsorption (outer-sphere) and ligand exchange (inner-sphere) reactions. Both trigonal (boric acid) and tetrahedral (borate) boron are complexed on the HFO surface, and a mechanism where trigonal boric acid in solution reacts to form either trigonal or tetrahedral surface complexes is proposed based upon the spectroscopic results. The presence of outer-sphere boric acid complexes can be explained based on the Lewis acidity of the B metal center, and this complex has important implications for boron transport and availability. Outer-sphere boric acid is more likely to leach downward in soils in response to water flow. Outer-sphere boron would also be expected to be more available for plant uptake than more strongly bound boron complexes, and may more readily return to the soil solution when solution concentrations decrease. Copyright © 2003 Elsevier Science Ltd 1