Preparation and properties of some hydroxy-aluminium beidellites

Brindley, G. W.; Sempels, R. E.

doi:10.1180/claymin.1977.012.3.05

Cited by 356 publications

(159 citation statements)

References 6 publications

Supporting

Mentioning

148

Contrasting

Unclassified

Order By: Relevance

“…The spectrum of APS exhibited characteristic bands of the alkyl chain at 2960, 2931 and 2872 cm 1 ; characteristic bands of the primary amine at 3385, 1615 and 1485 cm 1 ; a characteristic band of C-N at 1146 cm 1 ; a characteristic band of Si-O-C at 1100 cm 1 . The spectrum of APSHC exhibited characteristic bands of the primary ammonium ion at 3000-2800, 2034, 1610 and 1486 cm 1 ; a characteristic band of silanol group at 3500 cm 1 ; a characteristic band of Si-O-Si at 1040 cm 1 . From the results, it was found that the neutralization and hydrolysis of APS by hydrochloric acid solution resulted in the protonated ammonium ions and siloxane linkages.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Polyvinyl Alcohol on the Synthesis of Silica-Pillared Clay by Using 3-Aminopropyltriethoxysilane

Nakao

Nogami

2005

J. Ceram. Soc. Japan

View full text Add to dashboard Cite

Silica pillared clays with large interlayer distance were synthesized by the simultaneous intercalation of 3-aminopropyltriethoxysilane APS and polyvinyl alcohol PVA . Characterization of the synthetic silica pillared clay was done by X-ray diffraction measurement, nitrogen adsorption-desorption measurement and X-ray fluorescence analysis. The gallery height of the synthesized pillared clay was 1.3 nm in the presence of PVA, and it was found that the gallery height was twice as large as that of the pillared clay synthesized without using PVA. The specific surface area and pore volume of the pillared clay obtained with PVA were larger than those obtained without PVA. It was confirmed that the interlayer distance was enlarged with increase in the amount of pillaring precursors only by using PVA. 1 -3 Silica is one of the oxides of interest to obtain thermally stable and catalytically active pillared clays. Silica-pillared clays have been synthesized from a titania-silica or iron oxide-silica complex sol, because silica precursors are silicate anions which cannot enter between the negatively charged clay sheets. 4 -6 In spite of the large interlayer distance of the sol pillared clay, the pores were mainly micropores due to the multilayer stacking of the nanosize sol particles between the silicate layers. The mesoporous sol pillared clays have been synthesized by using surfactants.5 ,7 -9 On the other hand, a silica-pillared montmorillonite has been synthesized using ion exchangeable aminopropyltriethoxysilane APS instead of inorganic precursors. The intercalation of APS was expected to expand the interlayer distance due to the polycondensation by hydrolysis.10 However, there was no significant increase in the basal spacing even though the silica content significantly increased with the APS. The porosities were not increased by the addition of an excess APS for ion exchange capacity. Kaneko et al. have investigated the structure and the properties of the polysiloxane made from APS.11 The polysiloxane was dispersed in water. Pillared clays having the large surface areas and pore volumes have been prepared by introducing cationic oligomers using polyvinyl alcohol PVA .12 -15 The PVA presence in the interlayer space retained the distance between the silicate layers expanded. PVA was incorporated into the interlayer region

show abstract

Section: Resultsmentioning

confidence: 99%

“…1, the infrared spectra of the clay and APSHC-clay complex before calcination indicate the existence of ammonium groups. The spectrum of APSHC-clay complex exhibited characteristic bands of the primary ammonium ion at 3000-2800, 2025 and 1606 cm 1 . These bands were absent in the spectrum of Montmorillonite.…”

Section: Resultsmentioning

confidence: 99%

Effect of Polyvinyl Alcohol on the Synthesis of Silica-Pillared Clay by Using 3-Aminopropyltriethoxysilane

Nakao

Nogami

2005

J. Ceram. Soc. Japan

View full text Add to dashboard Cite

show abstract

“…The typical porous properties of various porous materials are summarized in figure 1 [1]. Porous ceramics with small pore sizes are generally gels, zeolites, Porous ceramics with 2D structures are typically observed in activated carbons [9] and pillared clays [10,11]. Activated carbons are prepared by reaction at elevated temperatures of various carbonaceous precursors with oxidizing gases (physical activation) or oxidizing chemicals (chemical activation).…”

Section: Introductionmentioning

confidence: 99%

Porous ceramics mimicking nature—preparation and properties of microstructures with unidirectionally oriented pores

Okada

Isobe

Katsumata

et al. 2011

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

Porous ceramics with unidirectionally oriented pores have been prepared by various methods such as anodic oxidation, templating using wood, unidirectional solidification, extrusion, etc. The templating method directly replicates the porous microstructure of wood to prepare porous ceramics, whereas the extrusion method mimics the microstructures of tracheids and xylems in trees. These two methods are therefore the main focus of this review as they provide good examples of the preparation of functional porous ceramics with properties replicating nature. The well-oriented cylindrical through-hole pores prepared by the extrusion method using fibers as the pore formers provide excellent permeability together with high mechanical strength. Examples of applications of these porous ceramics are given, including their excellent capillary lift of over 1 m height which could be used to counteract urban heat island phenomena, and other interesting properties arising from anisotropic unidirectional porous structures.

show abstract

“…A aplicação de esmectitas pilarizadas como adsorventes é sugerida, por estes materiais apresentarem pilares que mantêm separadas as camadas da estrutura da argila e propiciam que as dimensões de suas cavidades se tornem bem superiores às das zeólitas [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46] . Neste trabalho foi feita uma avaliação sobre o uso de esmectita pilarizada na adsorção de Cu(II), Ni(II) e Co(II), sendo selecionada uma amostra de esmectita da região noroeste do estado do Pará, que foi submetida à pilarização mista com poliidroxicátions de zircônio e titânio.…”

Section: Introductionunclassified

Aplicação de Zr/Ti-PILC no processo de adsorção de Cu(II), Co(II) e Ni(II) utilizando modelos físico-químicos de adsorção e termodinâmica do processo

Guerra¹,

Airoldi²,

Lemos³

et al. 2008

Quím. Nova

View full text Add to dashboard Cite

Recebido em 26/6/07; aceito em 10/8/07; publicado na web em 26/2/08 APPLICATION OF Zr/Ti-PILC IN THE ADSORPTION PROCESS OF Cu(II), Co(II) and Ni(II) USING ADSORPTION PHYSICO-CHEMICAL MODELS AND THERMODINAMICS OF THE PROCESS. The aim of this investigation is to study how Zr/Ti-PILC adsorbs metals. The physico-chemical proprieties of Zr/Ti-PILC have been optimized with pillarization processes and Cu(II), Ni(II) and Co(II) adsorption from aqueous solution has been carried out, with maximum adsorption values of 8.85, 8.30 and 7.78 x10 -1 mmol g -1 , respectively. The Langmuir, Freundlich and Temkin adsorption isotherm models have been applied to fit the experimental data with a linear regression process. The energetic effect caused by metal interaction was determined through calorimetric titration at the solid-liquid interface and gave a net thermal effect that enabled the calculation of the exothermic values and the equilibrium constant.Keywords: adsorption isotherms; metals; Zr/Ti -pillared clay. INTRODUÇÃOA adsorção de metais por superfícies minerais é um processo reconhecidamente importante que controla a biodisponibilidade dos metais em ambientes aquáticos [1][2][3][4][5][6][7][8][9] . O tratamento clássico de efluentes contendo metais envolve processos físico-químicos de precipitação, troca iônica, adsorção e extração por solventes, sendo mais utilizado o de precipitação, que é inadequado no tratamento de grandes volumes de efluentes, devido à baixa eficiência e elevados custos 10 . Neste caso, é mais recomendado o uso de recursos naturais sem tratamento prévio, como solos argilosos ferruginosos ricos em substân-cias húmicas 11 e, também, materiais naturais quimicamente modificados, como exemplos zeólitas naturais impregnadas com materiais magnéticos 12,13 e argilas modificadas por processo de pilarização ou intercalação. Tais materiais se enquadram no grupo de materiais porosos, desenvolvidos pela engenharia de materiais, com ampla aplicação em catálise heterogênea 14 e como adsorventes [15][16][17][18][19][20][21] .Com a evolução das pesquisas em busca de novos materiais que fossem utilizados como adsorventes, surgiram os materiais meso e microporosos, em particular as zeólitas ou peneiras moleculares, que atuam efetivamente com alto poder adsortivo, provocado por suas propriedades texturais. No decorrer do avanço das pesquisas surgiram as argilas pilarizadas com diversos polioxicátions, que produziram resultados satisfatórios em processos de adsorção. Vários metais pesados foram testados em meio líquido com adsorventes minerais quimicamente modificados, sendo que os resultados obtidos mostraram que as argilas pilarizadas são bastante eficientes em processos de adsorção 9-13 . Diversos estudos comprovam a eficiência das argilas em processos adsortivos e catalíticos, sendo que as argilas mais comumente empregadas em estudos de adsorção pertencem ao grupo da esmectita, principalmente a montmorilonita [14][15][16][17][18] .Estudos de adsorção de cobre realizados com amostras de esmectitas pilarizadas com pilare...

show abstract

Preparation and properties of some hydroxy-aluminium beidellites

Cited by 356 publications

References 6 publications

Effect of Polyvinyl Alcohol on the Synthesis of Silica-Pillared Clay by Using 3-Aminopropyltriethoxysilane

Effect of Polyvinyl Alcohol on the Synthesis of Silica-Pillared Clay by Using 3-Aminopropyltriethoxysilane

Porous ceramics mimicking nature—preparation and properties of microstructures with unidirectionally oriented pores

Aplicação de Zr/Ti-PILC no processo de adsorção de Cu(II), Co(II) e Ni(II) utilizando modelos físico-químicos de adsorção e termodinâmica do processo

Contact Info

Product

Resources

About