Progress 07/01/09 to 06/30/14
Outputs
Target Audience: Farmers People involved in remediation Environmental consulting companies Employees of Environmental Protection Agency Employees of Nuclear Regulatory Commission Water treatment people Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Training of students How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
There is a need to explore the synthesis and characterization of layered double hydroxides (LDHs) and organoclays which will selectively take up oxyanions such as nitrate and phosphate and toxic oxyanions such as chromate, perchlorate, arsenate, arsenite, selenate and selenite which may contaminate soils and groundwater worldwide. Two types of LDHs, hydrotalcite and hydrocalumite with different composition of layers and interlayers were investigated for the removal of arsenite from solutions. The kinetics study showed that anion exchange process was very fast and apparently attained a steady-state in the range of 8-16 hrs. Arsenite removal was found to be 87.5% and 83.6% with the nitrate forms of hydrotalcite and hydrocalumite, respectively. The uptake process was anion exchange in hydrotalcite-type LDH but possibly some dissolution-reprecipitation occurred with hydrocalumite-type LDH. Synthetic Zn-Al-SO4LDH was evaluated for the removal of arsenite and arsenate from a simulated soil solution. The Zn-Al-SO4was synthesized using a hydrothermal method. The results of the experiments revealed that the adsorption isotherms of arsenite and arsenate on the Zn-Al-SO4LDHs can be described well with Langmuir isotherm and maximum adsorption capacities were calculated to be 34.24 and 47.39 mg/g for arsenite and arsenate, respectively. The adsorption kinetics of arsenate followed pseudo-second order while arsenite uptake showed better correlation with intra-particle diffusion model. Furthermore, the effects of two major coexisting and competing divalent anions such as SO4 and CO3 on the uptake of arsenite and arsenate were studied and the results showed that CO3 had greater adverse effect on the uptake of arsenite and arsenate by Zn-Al-SO4 than SO4. Based on XRD results, the main adsorption mechanism of arsenite and arsenate might be the exchange on the external surfaces and edges of Zn-Al-SO4 LDHs with some exchange taking place in the interlayers. The organoclay, Closite10A, synthesized using benzyldimethyldodecylammonium (BDDA) chloride, showed the highest value, 0.260 plus or minus 0.006 meq/g for uptake of perchlorate. On the other hand, Nanomer 1.30E, prepared by using octadecylammonium (ODA) bromide, gave the lowest value of 0.057 plus or minus 0.006 meq/g for perchlorate uptake. Among the Nanomer samples, the higher the X-ray diffraction (001) ‘d’ value, the higher is the perchlorate uptake. The organoclay with dimethyldioctadecylammonium (DMDA) bromide surfactant (Nanomer 1.42E) gave the highest perchlorate uptake (0.170 plus or minus 0.003 meq/g) with a (001) ‘d’ value of 3.56 nm while Nanomer 1.30E, prepared by using ODA bromide, gave the lowest value for perchlorate uptake (0.057 plus or minus 0.006 meq/g) with a (001) ‘d’ value of 2.25 nm. In the above two cases there was a correlation of higher perchlorate uptake with larger (001) ‘d’ value. The main factor that controls the perchlorate uptake, however, is residual positive charge in these organoclays. The mechanism of uptake of perchlorate is by anion exchange of Cl- or Br- which are electrostatically bonded with the excess surfactant in organoclays. Organosilicas, which are analogous to organoclays have also shown selective uptake of perchlorate. Oraganosilicas such as MCM-41 and MCM-48 and composites of rice husks with MCM-48 were synthesized and characterized by powder X-ray diffraction (XRD). Various MCM-41 mesoporous materials were prepared at room temperature using different surfactants. MCM-48 silica and its composites with rice husks were synthesized under hydrothermal conditions using cetyltrimethylammonium (CTMA) bromide and rice husks. Organoclays were compared with organosilicas for their perchlorate uptake. Among the MCM-41 materials, the sample prepared with octadecyltrimethylammonium (ODTMA) chloride showed the highest perchlorate uptake capacity of 0.227 plus or minus 0.006 meq/g while MCM-48 showed the highest perchlorate uptake capacity of 0.437 plus or minus 0.011 meq/g among all the oraganosilicas and organoclays tested. ODTMA chloride was used to prepare organosilicas such as MCM-41 at room temperature while MCM-48 and a mesoporous layered organosilica (MCM-50) were synthesized under hydrothermal conditions using CTMA bromide. These synthetic organosilicas in addition to a commercially available organoclay, Cloisite 10A were characterized by powder XRD and tested with the occluded surfactant as adsorbents for perchlorate. The organosilicas were used for comparing with organoclay for perchlorate uptake kinetics. The results showed that the highest perchlorate uptake capacities were achieved with MCM-48 silica (0.421 plus or minus 0.007 meq/g) followed by mesoporous layered organosilica (0.400 plus or minus 0.006 meq/g). Cloisite 10A and MCM-41 silica adsorbed 0.280 plus or minus 0.003 and 0.246 plus or minus 0.003 meq/g of perchlorate, respectively. Kinetics studies showed that the adsorption followed pseudo-second-order kinetics model. Langmuir model fitted well with perchlorate adsorption. We tested two organosilicas and one organoclay for nitrate uptake. ODTMA chloride was used to prepare MCM-41 at room temperature while CTMA bromide was used to synthesize MCM-48 and layered organosilica material under hydrothermal conditions. These synthetic organosilica materials, in addition to a commercially available organoclay, Cloisite®10A, were characterized by powder XRD and tested with the occluded surfactant as sorbents for nitrate. The results showed that the highest nitrate uptake capacities were achieved with Cloisite® 10A (0.359±0.003 meq/g) followed by a layered organosilica (0.287±0.008 meq/g). MCM-48and MCM-41 silica adsorbed 0.096±0.002 and 0.157±0.005 meq/g of nitrate, respectively. Kinetics studies showed that the adsorption followed pseudo-second-order kinetic model. Layered organosilica gave a good fit to the Langmuir model. An organoclay was prepared using montmorillonite and hexadecylpyridinium chloride (HDPyCl) and tested for the removal of nitrate and perchlorate anions from aqueous solutions. Powder XRD analysis of the above organoclay showed a large basal spacing of 40.27A with the intercalation of HDPy cations in the interlayers in a paraffin-type bilayer arrangement. The nitrate and perchlorate uptakes by this organoclay could be described well using the Langmuir isotherm while their uptake kinetics fitted well to the pseudo-second order model. The maximum adsorption capacities of nitrate and perchlorate by the organoclay, HDPy-montmorillonite were calculated at 1.11 and 0.67mmol/g, respectively. Furthermore, the uptakes of nitrate and perchlorate by HDPy-montmorillonite were found to be highly selective in the presence of Cl, SO4 and CO3, the most abundant naturally occurring anions. Several organoclays were synthesized from different types of high charge synthetic clays using ODTMA chloride or polyethylenimine (PEI). Two alumina pillared clays were also prepared using two naturally occurring montmorillonites. These organic–clay and inorganic–clay nanocomposites were characterized by XRD and tested for perchlorate uptake. The results showed that the highest perchlorate uptake capacity of 0.436 ± 0.001 was achieved with ODTMA Na-3-mica followed by 0.269 ± 0.016 meq/g with ODTMA Na-2-mica. The uptake of perchlorate by synthetic Na-n-micas is as follows: ODTMA Na-3-mica > ODTMA Na-2-mica > ODTMA Na-1-mica > ODTMA Na-4-mica. The uptake of perchlorate by the ODTMA Na-n-micas could be attributed to exchange with chloride ions of the neutral surfactant occluded in between cationic chains during the cation exchange process. Organoclays prepared with PEI and hydroxy Al polymer pillared clays and their calcined counterparts showed little or no uptake because no excess positive charge exists in these unlike in organoclays.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Seliem, M. K., S. Komarneni, T. Byrne, F. S. Cannon, M. G. Shahien, A. A. Khalil, I. M. Abd El-Gaid. 2013. Removal of nitrate by synthetic organosilicas and organoclay: Kinetic and isotherm studies. Separation and Purification Technology 110:181-187.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Komarneni, S., A. R. Aref, S. Hong, Y. D. Noh, F. S. Cannon and Y. Wang. 2013. Organoclays of high-charge synthetic clays and alumina pillared natural clays: perchlorate uptake. Applied Clay Science 80-81:340-345.
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Bagherifam, S., S. Komarneni, A. Lakzian, A. Fotovat, R. Khorasani, W. Huang, J. Ma, S. Hong, and Y. Wang. 2014. Evaluation of Zn-Al-SO4 layered double hydroxide for removal of arsenite and arsenate from a simulated soil solution: Isotherms and kinetics. Applied Clay Science 95:119-125.
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Bagherifam, S., S. Komarneni, A. Lakzian, A. Fotovat, R. Khorasani, W. Huang, J. Ma, S. Hong, F. S. Cannon and Y. Wang. 2014. Highly selective removal of nitrate and perchlorate by organoclay. Applied Clay Science 95:126-132.
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Progress 10/01/12 to 09/30/13
Outputs
Target Audience: Farmers, people involved in remediation, environmental consulting companies, Environmental Protection Agency employees, Nuclear Regulatory Commission Employees, and water treatment people. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? One PSU graduate student and two visiting students were trained. How have the results been disseminated to communities of interest? The results were disseminated through journal publications. What do you plan to do during the next reporting period to accomplish the goals? We will synthesize different organoclays and use them for the uptake of different anions.
Impacts
What was accomplished under these goals?
Organoclays were synthesized and selective uptake of perchlorate, nitrate and aresenate were investigated.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Seliem, M. K., S. Komarneni, T. Byrne, F. S. Cannon, M. G. Shahien, A. A. Khalil, I. M. Abd El-Gaid. 2013. Removal of perchlorate by synthetic organosilicas and organoclay: Kinetics and isotherm studies. Applied Clay Science 71: 2126.
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Progress 10/01/11 to 09/30/12
Outputs
OUTPUTS: There is a need to explore layered double hydroxides (LDHs) and organoclays which may selectively take up oxyanions such as nitrate, phosphate, chromate, perchlorate, arsenate, arsenite, selenate and selenite that may contaminate soils and groundwater. In this study, octadecyltrimethylammonium (ODTMA) chloride was used to prepare organosilicas such as MCM-41 at room temperature while MCM-48 and a mesoporous layered organosilica (MCM-50) were synthesized under hydrothermal conditions using cetyltrimethylammonium (CTMA) bromide. These synthetic organosilicas in addition to a commercially available organoclay, Cloisite 10A were characterized by powder X-ray diffraction (XRD) and tested with the occluded surfactant as adsorbents for perchlorate. The organosilicas were used for comparing with organoclay for perchlorate uptake kinetics. The Adsorption data were modeled using the Langmuir and Freundlich adsorption isotherms. Adsorption kinetics data were tested using pseudo-first-order, pseudo-second-order and intraparticle (in pores of MCM-41 and MCM-48 or interlayers in the case of layered silica and organoclay, Cloisite) diffusion models. The results showed that the highest perchlorate uptake capacities were achieved with MCM-48 silica (0.421 plus or minus 0.007 meq/g) followed by mesoporous layered organosilica (0.400 plus or minus 0.006 meq/g). Cloisite 10A and MCM-41 silica adsorbed 0.280 plus or minus 0.003 and 0.246 plus or minus 0.003 meq/g of perchlorate, respectively. Kinetics studies showed that the adsorption followed pseudo-second-order kinetics model. The good fit of the experimental data and the values of correlation coefficients indicated the applicability of Langmuir model to perchlorate adsorption in the present study. PARTICIPANTS: Sridhar Komarneni, Principal investigator, Department of Crop and Soil Sciences. He contributed to the ideas and overall direction for the research, supervised students and contributed in writing papers. Moaz K. Seliem, visiting student from Egypt, carried out preparation of organoclays and organosilicas and perchlorate and nitrate anion exchange experiments. Robert Parette, student in Department of Civil and Environmental Engineering analyzed perchlorate solutions and contributed towards writing in which he has authorship. Fred S. Cannon, Professor in Department of Civil and Environmental Engineering contributed towards writing in which he has authorship. Hiroaki Katsuki, Saga Ceramics Research Laboratory, 3037-7, Arita-machi, Saga 844-0024, Japan, carried out SEM analyses and contributed in writing paper in which he has authorship. M. G. Shahien, Professor in Geology Department, Faculty of Science, Beni-Sueif University, Egypt., contributed to ideas for research. A. A. Khalil, Professor in Refractories, Ceramics and Building Materials Department, National Research Center, Dokki, Cairo, Egypt, contributed to ideas for research. I. M. Abd El-Gaid, Professor in Geology Department, Faculty of Science, Beni-Sueif University, Egypt, contributed to ideas for research. TARGET AUDIENCES: Farmers People involved in remediation Environmental consulting companies Employees of Environmental Protection Agency Employees of Nuclear Regulatory Commission Water treatment people. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This project deals with the development of synthetic layered double hydroxides and organoclays for the remediation of soils and water contaminated with oxyanions such as nitrate and phosphate and toxic oxyanions such as arsenate, arsenite, chromate, perchlorate, selenate and selenite. The above materials being developed are expected to be useful for remediation of soils and water contaminated with oxyanions.
Publications
- Seliem, M. K., S. Komarneni, R. Parette, H. Katsuki, F. S. Cannon, M. G. Shahien, A. A. Khalil, and I. M. Abd El-Gaid. 2011. Perchlorate uptake by organosilicas, organo-clay minerals and composites of rice husk with MCM-48. Applied Clay Science 53:621-626.
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Progress 10/01/10 to 09/30/11
Outputs
OUTPUTS: There is a need to explore layered double hydroxides (LDHs) and organoclays which may selectively take up oxyanions such as nitrate, phosphate, chromate, perchlorate, arsenate, arsenite, selenate and selenite that may contaminate soils and groundwater. The organoclay, Closite10A, synthesized using benzyldimethyldodecylammonium (BDDA) chloride, showed the highest value, 0.260 plus or minus 0.006 meq/g for uptake of perchlorate. On the other hand, Nanomer 1.30E, prepared by using octadecylammonium (ODA) bromide, gave the lowest value of 0.057 plus or minus 0.006 meq/g for perchlorate uptake. Among the Nanomer samples, the higher the X-ray diffraction (001) 'd' value, the higher is the perchlorate uptake. The organoclay with dimethyldioctadecylammonium (DMDA) bromide surfactant (Nanomer 1.42E) gave the highest perchlorate uptake (0.170 plus or minus 0.003 meq/g) with a (001) 'd' value of 3.56 nm while Nanomer 1.30E, prepared by using ODA bromide, gave the lowest value for perchlorate uptake (0.057 plus or minus 0.006 meq/g) with a (001) 'd' value of 2.25 nm. Among the Closite samples, Closite 15A and 20A have the same surfactant but different 'd' values because different concentrations of surfactant were used for synthesis and in these two cases there was a correlation of higher perchlorate uptake with larger (001) 'd' value. Although, there was a correlation of higher perchlorate uptake with larger (001) 'd' value, the main factor that controls the perchlorate uptake is residual positive charge in these organoclays. The mechanism of uptake of perchlorate is by anion exchange of Cl- or Br- which are electrostatically bonded with the excess surfactant in organoclays. During the course of this research we discovered that organosilicas, which are analogous to organoclays have also shown selective uptake of perchlorate. A variety of oraganosilicas such as MCM-41 and MCM-48 and composites of rice husks with MCM-48 were synthesized under an array of conditions and characterized by powder X-ray diffraction (XRD). Various MCM-41 mesoporous materials were prepared at room temperature using different surfactants. MCM-48 silica and its composites with rice husks were synthesized under hydrothermal conditions using cetyltrimethylammonium (CTMA) bromide and rice husks. Both untreated and carbonized rice husks were used for preparing composites of rice husk with MCM-48. Organoclays were compared with organosilicas for their perchlorate uptake. Among the MCM-41 materials, the sample prepared with octadecyltrimethylammonium (ODTMA) chloride showed the highest perchlorate uptake capacity of 0.227 plus or minus 0.006 meq/g while MCM-48 showed the highest perchlorate uptake capacity of 0.437 plus or minus 0.011 meq/g among all the oraganosilicas and organoclays tested here. The uptake of perchlorate by organosilicas and organoclays is due to residual positive charge on the surfactants located in the mesopores of organosilicas and interlayers of organoclays. Recent experiments showed that an organoclay, Closite10A has a better nitrate uptake capacity than either MCM-41 or MCM-48 mesoporous organosilicas. Further nitrate uptake studies are continuing. PARTICIPANTS: Sridhar Komarneni, Principal investigator, Department of Crop and Soil Sciences. He contributed to the ideas and overall direction for the research, supervised students and contributed in writing papers. Moaz K. Seliem, visiting student from Egypt, carried out preparation of anoclays and organosilicas and perchlorate and nitrate anion exchange xperiments. Joo Young Kim, student in Department of Civil and Environmental Engineering, carried out preparation of layered double hydroxides and organoclays and perchlorate anion exchange experiments and contributed towards writing in which she has authorship. Robert Parette, student in Department of Civil and Environmental Engineering analyzed perchlorate solutions and contributed towards writing in which he has authorship. Fred S. Cannon, Professor in Department of Civil and Environmental Engineering contributed towards writing in which he has authorship. Hiroaki Katsuki, Saga Ceramics Research Laboratory, 3037-7, Arita-machi, Saga 844-0024, Japan, carried out SEM analyses and contributed in writing paper in which he has authorship. TARGET AUDIENCES: Farmers, People involved in remediation, Environmental consulting companies, Employees of Environmental Protection Agency, Employees of Nuclear Regulatory Commission, Water treatment people PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This project deals with the development of synthetic layered double hydroxides and organoclays for the remediation of soils and water contaminated with oxyanions such as nitrate and phosphate and toxic oxyanions such as arsenate, arsenite, chromate, perchlorate, selenate and selenite. The above materials being developed are expected to be useful for remediation of soils and water contaminated with oxyanions.
Publications
- Komarneni, S., J. Y. Kim, R. Parette and F. S. Cannon. 2010. As-synthesized MCM-41 silica: New adsorbent for perchlorate. J. Porous Materials 17:651-656.
- Kim, J. Y., S. Komarneni, R. Parette, F. S. Cannon, and H. Katsuki. 2011. Perchlorate uptake by synthetic layered double hydroxides and organoclays. Applied Clay Science 51:158-164.
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Progress 10/01/09 to 09/30/10
Outputs
OUTPUTS: There is a need to explore the synthesis and characterization of layered double hydroxides (LDHs) and organoclays which will selectively take up oxyanions such as nitrate and phosphate and toxic oxyanions such as chromate, perchlorate, arsenate, arsenite, selenate and selenite which may contaminate soils and groundwater worldwide. The uptake of arsenite by LDHs was reported in last year's report. This year's report deals with arsenate uptake by LDHs and arsenate uptake mechanism. Hydrotalcite and hydrocalumite type LDHs were synthesized by coprecipitation at room temperature or higher with different compositions of layers and interlayers. The kinetics study showed that arsenate anion exchange was fast. The arsenate removal was 100% and 99.9% with nitrate form of hydrotalcite and hydrocalumite, respectively. Carbonate and chloride forms of hydrotalcite and chloride form of hydrocalumite removed 50-90% of arsenate from solution. The uptake capacities of hydrotalcite-type LDHs synthesized by different methods were also compared. Hydrotalcite-type LDH synthesized by co-precipitation method had greater uptake capacity than those synthesized by hydrothermal method because of smaller crystal size in the former. In the presence of much larger concentrations of other anions, the uptake of arsenate was reduced but it was still selective on LDH. The results of uptake were confirmed by powder X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM). In the case of chloride and nitrate forms of hydrotalcite the mechanism for arsenate anion exchange is topotactic. It involved breaking up of electrostatic interactions between the positive layers and anions in the interlayers and in the case of nitrate form of hydrocalumites the mechanism appears to be dissolution-precipitation. The perchlorate uptake capacities of hydrotalcite- and hydrocalumite-type layered double hydroxides (LDHs), and cationic surfactant modified clays were compared. Perchlorate uptake by both types of LDHs were determined and found to be in the range of 0.011 to 0.197 meq/g from a 2mM perchlorate solution. The nitrate form of Mg:Al LDH had the highest uptake of 0.197 plus or minus 0.033 meq/g while the carbonate form of LDH had the lowest uptake of 0.011 plus or minus 0.003 meq/g. Organoclays of octadecyl- trimethylammonium chloride (ODTMA), dodecyl- trimethylammonium bromide (DoDTMA), and hexadecyl- trymethylammonium bromide (HDTMA) removed perchlorate in the range of 0.025 to 0.348 meq/g from a 2mM perchlorate solution. Organoclay synthesized with HDTMA and a synthetic clay using a HDTMA amount equal to 5x of the cation exchange capacity (CEC) of clay exhibited the highest removal of perchlorate with 0.348 plus or minus 0.011 meq/g, while an organoclay of montmorillonite-DoDTMA has the lowest removal with 0.025 plus or minus 0.009 meq/g. Organophilic clay with larger interlayer space resulted in higher perchlorate uptake by exchange/adsorption on the residual charge of cationic surfactants. The uptake of perchlorate by LDH materials is by anion exchange on the surfaces and from the interlayers, the latter with nitrate form of hydrotalcite. PARTICIPANTS: Sridhar Komarneni, Principal investigator, Department of Crop and Soil Sciences. He contributed to the ideas and overall direction for the research, supervised students and contributed in writing papers. Kanchan Grover, student in Department of Crop and Soil Sciences, carried out preparation of layered double hydroxides and arsenate anion exchange experiments and contributed towards writing in which she has authorship. Joo Young Kim, student in Department of Civil and Environmental Engineering, carried out preparation of layered double hydroxides and organoclays and perchlorate anion exchange experiments and contributed towards writing in which she has authorship. Hiroaki Katsuki, Saga Ceramics Research Laboratory, 3037-7, Arita-machi, Saga 844-0024, Japan, carried out SEM analyses and contributed in writing paper. TARGET AUDIENCES: Farmers, People involved in remediation, Environmental consulting companies, Employees of Environmental Protection Agency, Employees of Nuclear Regulatory Commission, Water treatment people PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This project deals with the development of synthetic layered double hydroxides and organoclays for the remediation of soils and water contaminated with oxyanions such as nitrate and phosphate and toxic oxyanions such as arsenate, arsenite, chromate, perchlorate, selenate and selenite. The above materials being developed are expected to be useful for remediation of soils and water contaminated with oxyanions.
Publications
- Grover, K., S. Komarneni, and H. Katsuki. 2010. Synthetic hydrotalcite-type and hydrocalumite-type layered double hydroxides for arsenate uptake. Applied Clay Science 48:631-637.
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Progress 10/01/08 to 09/30/09
Outputs
OUTPUTS: There is a need to explore the synthesis and characterization of layered double hydroxides (LDHs) and organoclays which will selectively take up oxyanions such as nitrate and phosphate and toxic oxyanions such as chromate, perchlorate, arsenate, arsenite, selenate and selenite which may contaminate soils and groundwater worldwide. Two types of layered double hydroxides (LDHs), hydrotalcite and hydrocalumite with different composition of layers and interlayers were investigated for the removal of arsenite from solutions. The kinetics study showed that anion exchange process was very fast and apparently attained a steady-state in the range of 8-16 hrs. Arsenite removal was found to be 87.5% and 83.6% with the nitrate forms of hydrotalcite and hydrocalumite, respectively. Layered double hydroxides synthesized at room temperature showed higher uptake than those synthesized by hydrothermal method due to small crystal size (high surface area) of the former. As expected, calcined hydrotalcite showed higher uptake than uncalcined carbonate form of hydrotalcite. The uptake process was anion exchange in hydrotalcite-type LDH as confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) but possibly some dissolution-reprecipitation occurred with hydrocalumite-type LDH. PARTICIPANTS: Sridhar Komarneni, Principal investigator, Department of Crop and Soil Sciences. He contributed to the ideas and overall direction for the research, supervised students and contributed in writing papers. Kanchan Grover, student in Department of Crop and Soil Sciences, carried out preparation of layered double hydroxides and anion exchange experiments and contributed towards writing in which she has authorship. Hiroaki Katsuki, Saga Ceramics Research Laboratory, 3037-7, Arita-machi, Saga 844-0024, Japan, carried out SEM analyses and contributed in writing paper. TARGET AUDIENCES: Farmers People involved in remediation Environmental consulting companies Employees of Environmental Protection Agency Employees of Nuclear Regulatory Commission Water treatment people PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This project which has just begun deals with the development of synthetic layered double hydroxides and organoclays for the remediation of soils and water contaminated with oxyanions such as nitrate and phosphate and toxic oxyanions such as chromate, perchlorate, arsenate, arsenite, selenate and selenite. The above materials being developed are expected to be useful for remediation of soils and water contaminated with oxyanions.
Publications
- Grover, K., S. Komarneni, and H. Katsuki. 2009. Uptake of arsenite by synthetic layered double hydroxides. Water Research 43:3884-3890.
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