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Production of carbonaceous material from avocado peel for its application as alternative adsorbent for dyes removal

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Chinese Journal of Chemical Engineering 2016年第4期24卷 521-528页

作者： Carolyn Palma Lucia Lloret Antonio Puen Maira Tobar Elsa Contreras departamento de Ingenieria quimica Ambiental Universidad Tecnica Federico Santa Mafia Vicunia Mackenna 3939 Santiago Chile departamento de Ingenieria quimica Universidad de Santiago de Chile Alameda 3363 Santiago Chile

Adsorption processes have received special attention for contaminants removal thanks to their capability to gen- erate effluents with high quality as well as their simple design. In the current work, the agro-waste residue avo- cado peel is proposed to be used as alternative to conventional activated carbons whose use is sometimes restricted to high costs, upgraded by their exhausting after long term operations. The carbonization procedure was optimized and analyzed through factorial design and response surface methodology by evaluating temper- ature （400-900 ℃） and time （30-90 min） effects： optimal conditions were found at 900℃ and 65 min, gener- ating an adsorbent with 87.52 m2.g 1 of BET surface area, a mesopore volume of 74% and a zero point charge at 8.6. The feasibility of the carbonaceous material was proved for the removal of a variety of dyes by investigating substrate （10-50 mg.L 1） and solid （0.5-20 g.L-1） concentration effects and statistical significance： complete removal of Naphthol Blue Black and Reactive Black 5 was reached under optimal conditions （10 mg.L 1 and 20g.L 1 of dye and solid, respectively）, while Basic Blue 41 was eliminated by using 13.4 g. L- 1 of the adsorbent. Overall, dyes removal by adsorption on carbonized avocado peel is presented as a promising technology due to the low cost and easy availability of the precursor, as well as the straightforward generation, the satisfactory char- acteristics and the proved adsorption capacity of the adsorbent.

关键词： Avocado peelCarbonizationOptimizationAdsorptionDyes

Hadron resonances as rovibrational states

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Chinese Physics C 2021年第8期45卷 99-104页

作者： Douglas L.Bernardo Cristiano C.Bastos Antonio C.Pavao departamento de quimica Fundamental Universidade Federal de PernambucoRecife50740-540Brazil departamento de quimica Universidade Federal Rural de PernambucoRecife52171-900Brazil

A rovibrational model,including anharmonic,centrifugal,and Coriolis corrections,is used to calculate π,K,N,and ∑ orbital and radial *** four orbital excitations of the n meson correspond to the/?(1235),ti2(1670),63(2030),and π4(2250)*** first four radial excitations correspond to the π(1300),π(1800),π(2070),and 7t(2360)*** orbital excitations of the K meson are interpreted as the K_(1)(1270),K_(2)(1770),K_(3)(2320),and K_(4)(2500)resonances;its radial excitations correspond to the K(1460)and K(1830)*** N orbital excitations are identified with the N(1520),N(1680),N(2190),N(2220),and N(2600)*** first four radial excitations of the N family correspond to the N(1440),N(1880),N(2100),and N(2300)*** orbital excitations of the ∑ baryon are associated with the ∑(1670),∑(1915),∑(2100),and ∑(2250)resonances,whereas its radial excitations are identified with the ∑(1660),∑(1770),and ∑(1880)*** proposed rovibrational model calculations show a good agreement with the corresponding experimental values and allow for the prediction of hadron resonances,thereby proving to be useful for the interpretation of excited hadron spectra.

关键词： excited hadron spectrum orbital and radial resonances rovibrational states

Molecular modeling of the octacoordinated tetracarbonato-Nd(III), [Nd(CO_3)_4]^(5-), complex and its nonacoordinated fluoro- and aquo-adducts

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Journal of Rare Earths 2010年第6期28卷 847-853页

作者： S. P. Sinha Alfredo M. Simas Gustavo L. C. Moura Scientific Research & development departamento de quimica Fundamental CCEN Universidade Federal de Pernambuco

Theoretical investigation on the structures of the octacoordinated [Nd(CO3)4]5-and the nonacoordinated [Nd(CO3)***2]5-complexes, using the SPARKLE parameters of the lanthanides within MOPAC, revealed that they possessed dodecahedral and square antiprismatic structures respectively with an average Nd-O distance of 0.249 nm. These structures and the Nd-O distances agreed well with those experimentally found in the crystal structures. Replacing the water molecule with a fluoride ion or a mondentatecarbonato ligand resulted in a nonacoordinated distorted square antiprismatic structures where the trans-carbonato groups were twisted. The corresponding decacoordinated structures with two fluoride ions or a bidentatecarbonato group, [Nd(CO3)4·F2]7-and [Nd(CO3)5]7-, were also investigated. In both cases considerable twisting of the transcarbonato groups was observed.

关键词： lanthanides theoretical molecular models octacoordination carbonato complexes adducts MOPAC SPARKLE rare earths

Manifestation of external field effect in time-resolved photo-dissociation dynamics of LiF

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Chinese Physics B 2013年第7期22卷 140-147页

作者：孟庆田 A. J. C. Varandas department of Physics Institute of Physics and ElectronicsShandong Normal University departamento de quimica Universidade de Coimbra

The photo-dissociation dynamics of LiF is investigated with newly constructed accurate ab initio potential energy curves （PECs） using the time-dependent quantum wave packet method. The oscillations and decay of the wave packet on the adiabats as a function of time are given, which can be compared with the femtosecond transition-state （FTS） spectroscopy. The photo-absorption spectra and the kinetic-energy distribution of the dissociation fragments, which can exhibit the vibration-level structure and the dispersion of the wave packet, respectively, are also obtained. The investigation shows a blue shift of the band center for the photo-absorption spectrum and multiple peaks in the kinetic-energy spectrum with increasing laser intensity, which can be attributed to external field effects. By analyzing the oscillations of the wave packet evolving on the upper adiabat, an approximate inversion scheme is devised to roughly deduce its shape.

关键词： photo-dissociation dynamics time-dependent wave packet method photo-absorption spectra external field effect

P-functionalized carbon nanotubes promote highly stable electrocatalysts based on Fe-phthalocyanines for oxygen reduction: Experimental and computational studies

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Journal of Energy Chemistry 2022年第9期31卷 276-290,I0008页

作者： Beatriz Martinez-Sanchez Diego Cazorla-Amors Emilia Morallon departamento de quimica Fisica and Instituto Universitario de Materiales de Alicante(IUMA)University of Alicante Ap.99.03080 AlicanteSpain departamento de quimica Inorganica and Instituto Universitario de Materiales de Alicante(IUMA) University of AlicanteAp.9903080 AlicanteSpain

Iron(Ⅱ) phthalocyanines(FePc) supported on functionalized nanostructured carbon materials have been studied as electrocatalysts for the oxygen reduction reaction(ORR) in an alkaline medium. Herein, two types of carbon nanotubes(CNTs) have been explored as support, Single-Walled Carbon Nanotubes and Herringbone Carbon Nanotubes(SWCNTs and h CNTs, respectively), both electrochemically modified with ortho-aminophenylphosphonic acid(2APPA), which provides phosphate axial coordinating ligands for the immobilization of FePc molecules. All the catalysts were prepared via a facile incipient wetness impregnation method. Comprehensive experimental analysis together with density functional theory(DFT) calculations has demonstrated both the importance of the five-coordinated Fe macrocycles that favor the interaction between the FePc and the carbon support, as well as the effect of the CNT structure in the ORR. FePc axial coordination provides a better dispersion, leading to higher stability and a favorable electron redistribution that also tunes the ORR performance by lowering the stability of the reaction intermediates. Interestingly, such improvement occurs with a very low content of metal(~1 wt% Fe),which is especially remarkable when h CNT support is employed. This work provides a novel strategy for the development of Fe-containing complexes as precious metal-free catalysts towards the ORR.

关键词： Carbon nanotubes Iron phthalocyanine Oxygen reduction Electrocatalysis Axial ligand

Use of micellar liquid chromatography for rapid monitoring of fungicides post harvest applied to citrus wastewater

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Journal of Environmental Sciences 2016年第4期28卷 284-292页

作者： Juan Peris-Vicente Ana Marzo-Mas Pasqual Roca-Genovés Samuel Carda-Broch Josep Esteve-Romero departamento de quimica Fisica i Analitica ESTCE Universitat Jaume I 12071 Castello Spain

A method based on micellar liquid chromatography has been developed to simultaneously monitor four pesticides largely post-harvest applied to citrus：thiabendazole,pyrimethanil,o-phenylphenol and *** samples were filtered and directly injected without other treatment,thus avoiding extraction *** composition of the mobile phase was optimized using a chemometrical approach to achieve and excellent resolution to 0.07 mol/L SDS/5%,V/V 1-pentanol buffered at p H *** phase run through a C18 column at 1 m L/min at room *** detection was performing by UV–Visible absorbance using a wavelength program：0–10 min,305 nm（for thiabendazole）;10–12;265 nm（for pyrimethanil）and 12–18,220 nm（o-phenylphenol and imazalil）.The developed method was validated following the guidelines of the US Environmental Protection Agency in terms of：quantitation range,（0.5–4 to 15μg/m L）,linearity（r2〉0.9995）,sensitivity（LOD,0.18–1.4μg/m L）,precision（〈9.2%）,trueness（93.9%–103.7%）,and ruggedness（〈9.9%）.It was found that the fungicides remain up to eight days in surface water at outdoor *** method was used to screen the presence of the analytes in several waste water samples,and was proved to be useful in routine analysis.

关键词： Direct injection Micellar Pesticide Pollution Validation Water

Use of Mussel Shells as a Soil Amendment:Effects on Bulk and Rhizosphere Soil and Pasture Production

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Pedosphere 2012年第2期22卷 152-164页

作者： E.LVAREZ M.J.FERNNdeZ-SANJURJO N.SECO A.NUEZ departamento de Edafologia y quimica Agricola Escuela Politécnica SuperiorUniversidad de Santiago de CompostelaCampus Universitario

Large quantities of mussel shells （66000-94000 t year^-1）, an alkaline material that can be used as a soil amendment, are generated as waste in Galicia, NW Spain. A field trial was carried out by planting different pasture species in a Haplic Umbrisol using a randomized block design with four blocks and six treatments （not amended control or soil amended with lime, finely ground shell, coarsely ground shell, finely ground calcined shell or coarsely ground calcined shell） to compare the effects of lime and mussel shells additions on a soil with a low cation exchange capacity and high AI saturation. The trial was established in March 2007, and samples of plants and soil were collected when plots were harvested in summer 2008 （separating the bulk and rhizosphere soil）. The soils were analyzed for pH, total C, total N, available P, exchangeable cations, effective cation exchange capacity and available micronutrients. Dry matter yield was measured in all plots and plants were analyzed for nutrients. Application of mussel shells and the commercial lime resulted in an increase in pH and exchangeable Ca and a decrease in exchangeable Al and Al were most noticeable in the rhizosphere. The amendment of Ca in the plant. saturation. The stability of pH over time was high. These effects also had a positive effect on dry matter yield and concentration

关键词： dry matter production exchangeable A1 liming pasture quality soil nutrients

Sol–gel La2O3–ZrO2 mixed oxide catalysts for biodiesel production

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Journal of Energy Chemistry 2018年第2期27卷 565-572页

作者： Daniela Salinas Catherine Sepúlveda Néstor Escalona J.L.GFierro Gina Pecchi departamento de Fisicoquimica. Facultad de Ciencias quimicas Universidad de Concepcion Post Office 160-C Concepcion Chile departamento de quimica Facultad de Ciencias Universidad del Biobio Post Office 5-C Concepcion Chile departamento Ingenieria quimica y Bioprocesos Escuela de lngenieria Pontificia Universidad Catolica de Chile Avda. Vicuria Mackenna 4870 Maeul Santiago 7820436 Chile Centro de Investigacion en Nanotecnolagia y Materiales Avanzados (CIEN-UC) Pontificia Universidad Catolica de Chile Post Office 306 Santiago Chile departamento de quimica Fisica Facultad de Quimica Pontificia Universidad Catolica de Chile Post Offce 306 Santiago Chile Instituto de Catalisis y Petroleoquimica CSIC 28049 Madrid. Espana

Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel *** biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.

关键词： La2O3 -ZrO2 Sol-gel Biodiesel Canola oil Transesterification

Carbon dioxide fixation into cyclic carbonates at room temperature catalyzed by heteroscorpionate aluminum complexes

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Green Chemical Engineering 2022年第3期3卷 280-287页

作者： Felipe de la Cruz-Martinez Jose A.Castro-Osma Agustin Lara-Sanchez Universidad de Castilla-La Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de Ciencias y Tecnologias QuimicasCiudad Real13071Spain Instituto de Investigaciones quimicas(IIQ) Departamento de Quimica Inorganica and Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Consejo Superior de Investigaciones Cientificas(CSIC)and University of SevillaSevilla41092Spain Universidad de Castilla-La Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de FarmaciaAlbacete02071Spain

Novel mono-and bimetallic scorpionate aluminum compounds have been designed and characterized by spec-troscopic *** organometallics complexes,in combination with tetrabutylammonium bromide as cocatalyst,displayed good catalytic activity for the cycloaddition of styrene oxide and CO_(2) under ambient *** the compounds tested,monometallic complex 3 featuring diethylamino groups showed the highest catalytic *** catalytic system catalyzed the formation of cyclic carbonate products from their corresponding epoxides at room temperature and 1 bar of CO_(2) pressure in the absence of a solvent in good yields and excellent selectivities.

关键词： CO_(2) Epoxides Cyclic carbonates Aluminum complexes