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K M Parida - One of the best experts on this subject based on the ideXlab platform.
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a kinetic thermodynamic and mechanistic approach toward adsorption of methylene blue over water washed Manganese Nodule leached residues
Industrial & Engineering Chemistry Research, 2011Co-Authors: K M Parida, Swagatika Sahu, K H Reddy, Prakash C SahooAbstract:The present study aims to investigate and develop a cheap adsorption method for color removal from wastewater using water-washed Manganese Nodule leached residues (WMNLR) as adsorbent. The method was employed for the removal of methylene blue (MB), and the influence of various factors such as adsorbent dose, adsorbate concentration, electrolytes (NaCl, Na2HPO4, Na2SO4, NaNO3, and Na2CO3), temperature, and pH was studied. The equilibrium of adsorption was modeled by using the Langmuir and Freundlich isotherm models; the kinetic parameters and intraparticle diffusion were also then determined for the MB−WMNLR system. Kinetic data were well described by the pseudo second-order model. The thermodynamics of the MB−WMNLR system indicates spontaneous and endothermic nature of the process. The results in this study indicated that WMNLR was an attractive candidate for removing MB (98%), which could be reused up to four times without significant loss in its adsorption capacity.
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removal of phenolic compounds from aqueous solutions by adsorption onto Manganese Nodule leached residue
Journal of Hazardous Materials, 2010Co-Authors: K M Parida, Amaresh C PradhanAbstract:Abstract Manganese Nodule leached residue is a good adsorbent. Adsorption of phenol (PhOH) on water washed Manganese Nodule leached residue (WMNLR), waste materials from Manganese Nodules processing plant, has been investigated. The adsorbent (WMNLR) used for the removal of phenolic compounds were characterized by EDX, FTIR, SEM and BET surface area measurement before and after the adsorption process. Adsorption experiments were carried out to study the effect of various parameters like adsorbent dose, pH, adsorbate concentration, reaction time, temperature and calcination temperature. WMNLR calcined at 400 °C showed highest adsorption capacity. The equilibrium adsorption data for phenol was analyzed by using Langmuir isotherm model. The maximum adsorption of phenol was obtained at pH 3 (about 95% for adsorbent dose 1 g/L and 30 mg/L adsorbate concentration). The increase in percentage of adsorption with increase in temperature indicates that adsorption is endothermic in nature. The pseudo-second-order kinetics was followed in the adsorption process.
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potentiality of indian ocean Manganese Nodule and its leached residue as oxidation catalyst and adsorbent
Eighth ISOPE Ocean Mining Symposium, 2009Co-Authors: K M Parida, S S Dash, Amaresh C PradhanAbstract:The detailed physico-chemical characterization of Manganese Nodules (MN) and water washed Manganese Nodule leached residues (WMNLR) has been carried out on the basis of chemical analysis, XRD, TG/DTA, FT-IR, surface area and other surface properties. The surface area of MN samples dried at 110 o C ranges from 97 to 130 m 2 /g. Surface area, surface oxygen, surface hydroxyl group and surface acid sites of MN and WMNLR increase up to 400 o C and then decrease with further rise in calcination temperatures up to 700 o C. The catalytic activity of MN samples for CO oxidation and decomposition of VOCs such as acetone, methanol and 2-propanol has been performed in a static bed reactor. The catalytic activity of the calcined WMNLR samples was tested for single step oxidation of benzene to phenol, esterification of acetic acid with n-butanol and bromination of phenol. MN-400 and WMNLR-400 shows highest catalytic activity in the above mentioned reactions. MN and WMNLR are found to have good adsorption capacity for both cations and anions.
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surface characterization and catalytic evaluation of Manganese Nodule leached residue toward oxidation of benzene to phenol
Joint International Conference on Information Sciences, 2007Co-Authors: K M Parida, S S DashAbstract:Water washed Manganese Nodule leached residue (WMNLR) calcined at different temperatures was characterized by XRD, FTIR, TG-DTA, surface area, surface oxygen, and surface acid sites. Surface area, surface oxygen, surface hydroxyl group, and surface acid sites increase up to 400 °C and then decrease with further rise in calcination temperature up to 700 °C. The catalytic activity of the calcined samples was tested for single-step oxidation of benzene to phenol using hydrogen peroxide as the oxidant and acetic acid as the solvent at room temperature. The influence of various reaction parameters such as solvent, concentration of solvent, oxidant amount, time, temperature, and catalyst amount was studied to optimize the reaction conditions. WMNLR calcined at 400 °C showed the highest catalytic activity towards oxidation of benzene with 12.7% conversion and 98% selectivity.
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esterification of acetic acid with n butanol over Manganese Nodule leached residue
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: S S Dash, K M ParidaAbstract:Abstract Manganese Nodule leached residue (MNLR) was obtained as waste material after selective extraction of Cu, Co and Ni from Indian Ocean Manganese Nodule. MNLR was washed with water to remove sulphate and other impurities present in its surface. The catalytic activity of the waste material was tested for liquid phase esterification of acetic acid with n -butanol. The effect of reaction time, catalyst amount, temperature and mole ratio of reactants on esterification was studied to optimize the reaction conditions. Water-washed Manganese Nodule leached residue (WMNLR) calcined at 400 °C shows highest catalytic activity with 76.6% conversion having 100% selectivity towards n -butyl acetate. Esterification reaction follows first order kinetics with respect to acid and 0th order with respect to n -butanol. Conversion of C 1 –C 4 aliphatic acids with n -butanol follows the following order: formic > acetic > proponoic > n -butyric.
S S Dash - One of the best experts on this subject based on the ideXlab platform.
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potentiality of indian ocean Manganese Nodule and its leached residue as oxidation catalyst and adsorbent
Eighth ISOPE Ocean Mining Symposium, 2009Co-Authors: K M Parida, S S Dash, Amaresh C PradhanAbstract:The detailed physico-chemical characterization of Manganese Nodules (MN) and water washed Manganese Nodule leached residues (WMNLR) has been carried out on the basis of chemical analysis, XRD, TG/DTA, FT-IR, surface area and other surface properties. The surface area of MN samples dried at 110 o C ranges from 97 to 130 m 2 /g. Surface area, surface oxygen, surface hydroxyl group and surface acid sites of MN and WMNLR increase up to 400 o C and then decrease with further rise in calcination temperatures up to 700 o C. The catalytic activity of MN samples for CO oxidation and decomposition of VOCs such as acetone, methanol and 2-propanol has been performed in a static bed reactor. The catalytic activity of the calcined WMNLR samples was tested for single step oxidation of benzene to phenol, esterification of acetic acid with n-butanol and bromination of phenol. MN-400 and WMNLR-400 shows highest catalytic activity in the above mentioned reactions. MN and WMNLR are found to have good adsorption capacity for both cations and anions.
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surface characterization and catalytic evaluation of Manganese Nodule leached residue toward oxidation of benzene to phenol
Joint International Conference on Information Sciences, 2007Co-Authors: K M Parida, S S DashAbstract:Water washed Manganese Nodule leached residue (WMNLR) calcined at different temperatures was characterized by XRD, FTIR, TG-DTA, surface area, surface oxygen, and surface acid sites. Surface area, surface oxygen, surface hydroxyl group, and surface acid sites increase up to 400 °C and then decrease with further rise in calcination temperature up to 700 °C. The catalytic activity of the calcined samples was tested for single-step oxidation of benzene to phenol using hydrogen peroxide as the oxidant and acetic acid as the solvent at room temperature. The influence of various reaction parameters such as solvent, concentration of solvent, oxidant amount, time, temperature, and catalyst amount was studied to optimize the reaction conditions. WMNLR calcined at 400 °C showed the highest catalytic activity towards oxidation of benzene with 12.7% conversion and 98% selectivity.
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esterification of acetic acid with n butanol over Manganese Nodule leached residue
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: S S Dash, K M ParidaAbstract:Abstract Manganese Nodule leached residue (MNLR) was obtained as waste material after selective extraction of Cu, Co and Ni from Indian Ocean Manganese Nodule. MNLR was washed with water to remove sulphate and other impurities present in its surface. The catalytic activity of the waste material was tested for liquid phase esterification of acetic acid with n -butanol. The effect of reaction time, catalyst amount, temperature and mole ratio of reactants on esterification was studied to optimize the reaction conditions. Water-washed Manganese Nodule leached residue (WMNLR) calcined at 400 °C shows highest catalytic activity with 76.6% conversion having 100% selectivity towards n -butyl acetate. Esterification reaction follows first order kinetics with respect to acid and 0th order with respect to n -butanol. Conversion of C 1 –C 4 aliphatic acids with n -butanol follows the following order: formic > acetic > proponoic > n -butyric.
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studies on selenite adsorption using Manganese Nodule leached residues
Journal of Colloid and Interface Science, 2007Co-Authors: S S Dash, K M ParidaAbstract:Abstract Selenite adsorption on water-washed Manganese Nodule leached residues (WMNLR) was studied with the aim of detoxifying industrial effluents before their safe disposal into the environment. WMNLR, a solid waste material, was characterized with the help of XRD, FTIR, TG-DTA, pHpzc, BET surface area, surface oxygen, surface hydroxyl group, and chemical analyses. The adsorption behavior of WMNLR toward selenite was studied as a function of time, pH, temperature, and concentration of adsorbate and adsorbent. Increased adsorption capacity with rise in temperature indicates that the adsorption process was endothermic in nature. Based on the thermodynamic parameters such as the Gibbs free energy change, standard enthalpy change, and standard entropy change, the adsorption process was found to be spontaneous and endothermic in nature. Adsorption followed second-order kinetics. The adsorption capacity of the material was found to be 54.6 mg g−1 at 60 mg L−1 of selenite concentration at pH 5 in 3 h contact time.
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adsorption of hexavalent chromium on Manganese Nodule leached residue obtained from nh3 so2 leaching
Joint International Conference on Information Sciences, 2006Co-Authors: Sujata Mallick, S S Dash, K M ParidaAbstract:Abstract Adsorption of hexavalent chromium onto Manganese Nodule leached residues was investigated as a possible alternative to the conventional methods of its removal from aqueous synthetic solutions. Adsorption behavior was studied as a function of time, pH, temperature, and concentration of adsorbate and adsorbent in acetic acid–sodium acetate buffer medium. Cr (VI) removal was pH dependent and was found to be of a maximum at pH 3. The applicability of the Langmuir isotherm to the present system was tested. Increased adsorption capacity with increased temperature indicates that the adsorption reaction was endothermic in nature. Based on these studies, thermodynamic parameters such as Gibbs free energy change ( Δ G 0 ), standard enthalpy change ( Δ H 0 ), and standard entropy change ( Δ S 0 ) were calculated.
Christian Bussau - One of the best experts on this subject based on the ideXlab platform.
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new deep sea nematoda enoplida thoracostomopsidae oncholaimidae enchelidiidae from a Manganese Nodule area of the eastern south pacific
Zoologica Scripta, 1995Co-Authors: Christian BussauAbstract:Five new nematode species are described from a mangancsc Nodule area of the abyssal eastern South Pacific: Enoploides tyrannis sp. n., Paramesacanthion abyssorum sp. n., P. forcepssp. n. (all three Thoracostomopsidae), Phylloncholaimus immanis gen. et sp. n. (Oncholaimidac), and Eurystomina absoluta sp. n. (Enchelidiidae). They are characterized by large size (body length 5000–23000 μm), short tails (c = 17–33), and strongly cuticularizcd, barrel-shaped buccal cavities with large teeth. With the exception of one male of E. tyrannis from the surface of a Manganese Nodule, all other specimens were found in the sediment. The new species are sporadic in distribution and represented by few individuals.
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new deep sea tardigrada arthrotardigrada halechiniscidae from a Manganese Nodule area of the eastern south pacific
Zoologica Scripta, 1992Co-Authors: Christian BussauAbstract:Three new Tardigrada species are described from a Manganese Nodule area of thc abyssal castern South Pacific. Moebjergarctus mangunis gen. et sp.n. is characterized by its segmcntcd ccphalic cirri, club-shaped and forward bent primary clavae, spherical secondary clavae, spines on legs I, 11, 111, small clavoid papillae on legs IV, long cirri E, and corkscrew-shaped digits with simple claws. Angursa capsula sp.n. is distinguished by the presence of secondary and tertiary clavac, occurring as elevated cuticular areas, club-shaped primary clavae, short lateral cirri, short median cirrus, spines on legs I and hcmisphcrical, capsulc-shaped papillae on legs IV. Angursa lingua sp.n. is characterized by the presence of secondary and tertiary clavae, occurring as elevated cuticular areas, balloon-shaped primary clavae, long lateral cirri, long median cirrus, spines on legs I, clavoid papillae on legs IV and weakly broadened distal parts of cirri E, resulting in tongue-shaped swellings. A simple key to the species of Angursa is presented.
Hongmiao Pan - One of the best experts on this subject based on the ideXlab platform.
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The detection of magnetotactic bacteria in deep sea sediments from the east Pacific Manganese Nodule Province
Environmental Microbiology Reports, 2016Co-Authors: Yi Dong, Wuchang Zhang, Wenyan Zhang, Yuan Zhao, Tian Xiao, Hongmiao PanAbstract:Magnetotactic bacteria (MTB) are distributed ubiquitously in sediments from coastal environments to the deep sea. The Pacific Manganese Nodule Province contains numerous polymetallic Nodules mainly composed of Manganese, iron, cobalt, copper and nickel. In the present study we used Illumina MiSeq sequencing technology to assess the communities of putative MTB in deep sea surface sediments at nine stations in the east Pacific Manganese Nodule Province. A total of 402 sequence reads from MTB were classified into six operational taxonomic units (OTUs). Among these, OTU113 and OTU759 were affiliated with the genus Magnetospira, OTU2224 and OTU2794 were affiliated with the genus Magnetococcus and Magnetovibrio, respectively, OTU3017 had no known genus affiliation, and OTU2556 was most similar to CandidatusMagnetananas. Interestingly, OTU759 was widely distributed, occurring at all study sites. Magnetism measurements revealed that all sediments were dominated by low coercivity, non-interacting single domain magnetic minerals. Transmission electron microscopy confirmed that the magnetic minerals were magnetosomes. Our data suggest that diverse putative MTB are widely distributed in deep sea surface sediments from the east Pacific Manganese Nodule Province.
Horst U Oebius - One of the best experts on this subject based on the ideXlab platform.
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Parametrization and evaluation of marine environmental impacts produced by deep-sea Manganese Nodule mining
Deep-sea Research Part Ii-topical Studies in Oceanography, 2001Co-Authors: Horst U Oebius, Hermann J Becker, Susanne Rolinski, Jacek A. JankowskiAbstract:Abstract The evaluation of marine environmental impacts resulting from the exploitation of marine resources requires the numerical description, parametrization, and modelling of such processes in order to be able to transfer, compare, and forecast the effects of anthropogenic activities in the deep sea. One of the controversial effects is the formation and behaviour of sediment clouds as a consequence of anthropogenic activities on the seafloor. Since there is a need for reliable data, two subprojects of the “Interdisciplinary Deep-sea Environmental Protection Group (TUSCH)”-project “Impacts from Technical Activities on the Deep-Sea Ecosystem of the South East Pacific Offshore Peru (ATESEPP)” were devoted to the assembly of such data. Based on the German technical approach for deep-sea mining, the possible environmental impacts by a miner were estimated, the impacts on the seafloor were simulated and investigated by tests with large volume undisturbed sediment samples on board the research vessel and in the laboratory, and the results were evaluated and extrapolated. This report gives a comprehensive presentation of the physical problems, the technical approach, and the results of these investigations.
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geotechnical and sedimentological investigations of deep sea sediments from a Manganese Nodule field of the peru basin
Deep-sea Research Part Ii-topical Studies in Oceanography, 2001Co-Authors: Bernd Grupe, Hermann J Becker, Horst U OebiusAbstract:Abstract Deep-sea mining of Manganese Nodules will significantly modify the surface layer of deep sea. Surface sediments are mechanically disturbed, and a cloud of sediment particles suspended and re-deposited. Assessment of sedimentological and soil mechanical characteristics of undisturbed top layer sediments from a Manganese Nodule field of the Peru Basin are necessary to provide baseline data for soil mechanical estimations and for the physical and numerical modelling of environmental impacts of future ocean mining activities. This will assist the International Seabed Authority to make decisions on how to formulate the mining code, and will increase our understanding of sedimentation processes in the Peru Basin. The deployment of a new sampling device (maxicorer) guaranteed undisturbed sediment samples in which soil mechanics-related parameters were measured including sediment density, water content, shear strength, and penetration force. Data evaluation show a close relationship between the soil mechanical parameters and various sedimentological properties such as grain-size distribution, mineral composition and micro-structure. From the results it can be concluded that in the worst case a deep-sea Nodule mining vehicle would sink about 15–20 cm into the sea bed.