Synthesis and characterization of zeolite NaP using kaolin waste as a source of silicon and aluminum

Hildebrando, Edemarino Araujo; Gianesi, Christiano; Andrade, Bastos de; Angélica, Rômulo Simões; Valenzuela‐Díaz, Francisco Rolando; Neves, R. F.

doi:10.1590/s1516-14392014005000035

Cited by 55 publications

(25 citation statements)

References 23 publications

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“…Assim, a problemática maior desse processo é a construção das lagoas de sedimentação, já que as mesmas ocupam grandes áreas, além dos custos elevados para sua construção e manutenção. No entanto, esse resíduo, devido à sua composição mineralógica, tem sido usado como material de partida na síntese de zeólitas, como as fases A de Na, K, Ca e Mg [1][2][3][4][5], sodalita [6,7], tipo faujasita [8], fase P de Na [9] e analcima [10]. Zeólitas podem ser definidas como aluminossilicatos hidratados, do grupo dos metais alcalinos e alcalinos terrosos, com arranjo estrutural que apresenta cavidades e canais interconectados, com a presença de íons de compensação, como Na + , Ca 2+ , Mg 2+ e K + , e moléculas de H 2 O [11].…”

Section: Introductionunclassified

Efeito do envelhecimento da mistura reacional constituída por resíduo de caulim da Amazônia na síntese da zeólita faujasita

et al. 2017

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ResumoA etapa de pré-cristalização (envelhecimento) foi introduzida no processo de síntese da zeólita tipo faujasita. Nessa síntese, um resíduo caulinítico proveniente da região amazônica foi utilizado como fonte de Si e Al, já que o mesmo foi constituído principalmente por caulinita. O processo de síntese ocorreu em três etapas: 1) tratamento térmico do resíduo de caulim a 700 °C/2 h; 2) pré-cristalização da mistura reacional por 24 h à temperatura ambiente; e 3) processo hidrotermal a 90 °C por 1 a 10 h. A caracterização do material de partida, material pré-cristalizado e produtos de síntese foi feita por meio de difratometria de raios X, microscopia eletrônica de varredura e análise química. Os resultados confirmaram que o resíduo de caulim foi constituído principalmente por caulinita, o material obtido por meio da pré-cristalização foi amorfo e a formação da zeólita faujasita iniciou-se a partir de 5 h de síntese. A partir do tempo de 8 h de cristalização, a zeólita faujasita apresentou maior grau de ordem estrutural, porém zeólita P também foi formada. Palavras-chave: resíduo caulinítico, pré-cristalização, zeólita faujasita. AbstractThe pre-crystallization step (aging) was introduced in the faujasite synthesis process. In this synthesis, the kaolin waste from the Amazon region was used as Al and Si source, since it was composed primarily of kaolinite. The synthesis process followed three steps: 1) thermal treatment of kaolin waste at 700 °C/2 h; 2) pre-crystallization of reaction mixture for 24 h at room temperature; and (3) hydrothermal process at 90 °C for 1 to 10 h. The starting material, pre-crystallized material and synthesized products were characterized by X-ray diffraction, scanning electron microscopy and chemical analysis. The results confirmed that kaolin waste was composed primarily of kaolinite, the material obtained by pre-crystallization was amorphous, and the zeolite faujasite formation started at 5 h of synthesis. Zeolite faujasite had high structural order from the synthesis time of 8 h, however zeolite P was also formed.

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Section: Introductionunclassified

Efeito do envelhecimento da mistura reacional constituída por resíduo de caulim da Amazônia na síntese da zeólita faujasita

et al. 2017

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“…In addition, new low intensity peaks noted at 1508 and 1550 cm −1 were ascribed to the aromatic N-H secondary amine group [ 28 ]; other new peaks appearing around 3621 and 3738 cm −1 were ascribed to stretching vibrations of O−H group [ 29 ]. These spectral changes indicate the interactions between PAN nanofibers and NaHCO 3 functionalization by the formation of polar interactions between the functional groups of both components.…”

Section: Resultsmentioning

confidence: 99%

“…After the PAN nanofiber was treated with NaHCO3, the spectral peaks appearing at 1095, 1664 and 2931 cm −1 shifted to the lower wave number positions 1074, 1662, and 2925 cm −1 , respectively, while other peaks such as 1225, 1360, and 3319 cm −1 shifted to the higher wave number positions 1240, 1362, and 3321 cm −1 , respectively [28]. In addition, new low intensity peaks noted at 1508 and 1550 cm −1 were ascribed to the aromatic N-H secondary amine group [28]; other new peaks appearing around 3621 and 3738 cm −1 were ascribed to stretching vibrations of O−H group [29]. These spectral changes indicate the interactions between PAN nanofibers and NaHCO3 functionalization by the formation of polar interactions between the functional groups of both components.…”

Section: Ftir Analysismentioning

confidence: 94%

Comparative Removal of Lead and Nickel Ions onto Nanofibrous Sheet of Activated Polyacrylonitrile in Batch Adsorption and Application of Conventional Kinetic and Isotherm Models

2020

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We investigated the adsorption of lead (Pb2+) and nickel (Ni2+) ions by electrospun membranes of polyacrylonitrile (PAN) nanofiber activated with NaHCO3 (PANmod). Analysis by Fourier-transform infrared spectrometry (FTIR), field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDX) validated the functionalization of PAN nanofibers with NaHCO3, and the successful agglomeration of Pb2+ and Ni2+ onto PANmod. After a rapid uptake of the heavy metal ions (15 min), the equilibrium contact time was attained (60 min) following a linear increase of both adsorption capacity and removal efficiency. PANmod showed a better affinity for Ni2+ than Pb2+. The adsorption on PANmod was best described by the pseudo-second-order kinetic model for both studied models, supporting chemisorption. By varying the solution pH from 2.0 to 9.0, we found that the adsorption capacity followed an increasing trend, reaching a maximum at the pH of 7.0. Despite increasing adsorption capacities, the removal efficiency of both heavy metal ions exhibited a decreasing trend with increase in initial concentrations. The amount of PANmod directly affects the removal efficiency, with 0.7 and 0.2 g being the optimum dose for maximum uptake of Pb2+ and Ni2+, respectively. The Langmuir model fitted well the Pb2+ adsorption data suggesting monolayer adsorption, and the Freundlich model perfectly fitted the Ni2+ adsorption data, indicating heterogeneous adsorption. The estimated values of the mean free energy of adsorption in the D–R isotherm indicated a physical adsorption of both heavy metal ions into the surface of the PANmod.

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“…The band associated with Si-O deformation is detailed to be 1040 cm -1 . 37 The band at 796 cm −1 is assigned to the Si-O-Si symmetric stretch. 38 Besides, a strong peak at 544 cm -1 indicates the presence of Si-O-Al stretching vibrations.…”

Section: Resultsmentioning

confidence: 99%

RSM-BBD Optimization of Fenton-Like Degradation of 4-Nitrophenol Using Magnetite Impregnated Kaolin

Belachew

Fekadu

Abebe

2020

Air, Soil and Water Research

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In this work, we have reported a low-cost and environmentally friendly Fe3O4-modified activated kaolin (AK-Fe3O4) composite for efficient Fenton-like degradation of 4-nitrophenol (4-NP) and optimization of the degradation variables. The AK-Fe3O4 composites were characterized by Fourier transform infrared spectroscopy, powder x-ray diffraction, scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). X-ray diffraction confirms the syntheses of pure phases of Fe3O4 and AK-Fe3O4. The SEM image of the AK-Fe3O4 composite reveals the formation of a highly porous surface. The room temperature VSM analysis describes the superparamagnetic nature of AK-Fe3O4 composites with 25 emu/g magnetization values. Response surface methodology coupled with Box-Behnken design was used to optimize the 4-NP degradation (%) variables such as contact time (10-90 minutes), 4-NP concentration (10-30 mg/L), and pH (3-8). The high regression value ( R² = 0.9964 and adjusted R² = 0.9917) and analysis of variance ( P < .0001) show that the quadratic model can sufficiently explain the 4-NP degradation (%). The optimum 4-NP degradation was found to be 96.01% ± 1.89% using 1 mg/mL of AK-Fe3O4, 20 mg/L of 4-NP, 97.9 mmol/L of H2O2, and pH of 3 at the end of 75 minutes of reaction time. Moreover, the catalyst shows good recyclability and stability after 5 successive degradations of 4-NP. In general, a low-cost and magnetically separable AK-Fe3O4 composite is an effective Fenton-like catalyst for the degradation of 4-NP.

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Synthesis and characterization of zeolite NaP using kaolin waste as a source of silicon and aluminum

Cited by 55 publications

References 23 publications

Efeito do envelhecimento da mistura reacional constituída por resíduo de caulim da Amazônia na síntese da zeólita faujasita

Efeito do envelhecimento da mistura reacional constituída por resíduo de caulim da Amazônia na síntese da zeólita faujasita

Comparative Removal of Lead and Nickel Ions onto Nanofibrous Sheet of Activated Polyacrylonitrile in Batch Adsorption and Application of Conventional Kinetic and Isotherm Models

RSM-BBD Optimization of Fenton-Like Degradation of 4-Nitrophenol Using Magnetite Impregnated Kaolin

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