Microwave drying as an effective method to obtain porous carbon xerogels

Zubizarreta, Leire; Arenillas, A.; Menéndez, J.Á.; Pís, J.J.; Pirard, Jean‐Paul; Job, Nathalie

doi:10.1016/j.jnoncrysol.2008.06.003

Cited by 39 publications

(32 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…hours). Furthermore, according to some recent studies (Calvo et al, 2011a;Job et al, 2006;Leonard et al, 2005;Zubizarreta et al, 2008b) if the different evaporation conditions (i.e. the type of the solvent used, the temperature of evaporation, the carrier gas used during evaporation, use of vacuum, microwave heating, etc.)…”

Section: Dryingmentioning

confidence: 99%

“…This is due to, except in the case of subcritical drying, under supercritical and freezing conditions, it is necessary to perform solvent exchanges, which requires several days, and in the most extreme conditions of drying entails a substantial increase in production costs Tamon et al, 2000;Zhang et al, 2007). Consequently, the research in this field is being addressed to the development of faster and cheaper methods of synthesizing carbon gels in order to make them more attractive and competitive than the activated carbons used until now (Calvo et al, 2008Conceição et al, 2009;Tonamon et al, 2006;Zubizarreta et al, 2008b). Some of these works are based on the use of different types of electromagnetic radiation as a heating source for one or several stages of the synthesis process.…”

Section: Introductionmentioning

confidence: 99%

“…Some of these works are based on the use of different types of electromagnetic radiation as a heating source for one or several stages of the synthesis process. As will be explained in more detail in Section 2.4, microwave and ultrasonic radiation are the most widely investigated of the new synthesis techniques, being the results very promising not only because they meet the target of lower production times and costs but also they produce carbon gels with properties similar to those obtained using more established methods (Calvo et al, 2008Zubizarreta et al, 2008b). To increase the porosity of carbon gels or to enrich their chemical structure, carbon gels can be subjected to various activation, oxidation and doping processes.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Designing Nanostructured Carbon Xerogels

Calvo¹,

Menéndez²,

Arenillas³

2011

Nanomaterials

View full text Add to dashboard Cite

Section: Dryingmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Designing Nanostructured Carbon Xerogels

Calvo¹,

Menéndez²,

Arenillas³

2011

Nanomaterials

View full text Add to dashboard Cite

“…R and F are mixed with water in appropriate proportions, with the addition of a catalyst (usually Na 2 CO 3 ), and then aqueous solution is allowed to polycondensation. The obtained resorcinol-formaldehyde (RF) gels are subjected to dehydration, most often by the exchange of solvents [1], drying with supercritical CO 2 [1,2], drying at ambient temperature [3][4][5], microwave drying [6] or by freeze drying [7,8]. The products of drying are then subjected to thermal treatment to obtain carbon gels.…”

Section: Introductionmentioning

confidence: 99%

The effect of catalyst and heat treatment on the properties of carbon–metal composites

Osińska

2015

J Porous Mater

View full text Add to dashboard Cite

Carbon gel and carbon-nickel-palladium doped gels (C-Ni-Pd) were prepared by carbonising resorcinol-formaldehyde (RF) hydrogel and resorcinolformaldehyde-nickel-palladium (RF-Ni-Pd) hydrogels at 900°C in a nitrogen atmosphere. RF and RF-Ni-Pd hydrogels were synthesized through sol-gel polycondensation followed by ambient drying. The aim of this study was the determination of the effect of heat treatment in air at 450°C on the properties of C-Ni-Pd gels prepared using different Pd salts. In the present work, Ni was added as acetate whereas Pd was added as acetate (CA-Ni-Pd) and as chloride (CB-Ni-Pd). Samples were examined by scanning electron microscopy and X-ray diffraction. Surface area was characterized by N 2 adsorption at -195.5°C. Thermogravimetric analysis was carried out in order to determine the thermal characteristics of carbon gel and nickel-palladium composites in air atmosphere. CANi-Pd composite had a higher activity and two-phase reaction compared to the CB-Ni-Pd composite. Further improvement of the electrolyte diffusion into the particles of nickel and palladium was obtained by oxidative thermal treatment. During this process a structural modification of the material took place, consequently leading to changes in the electrochemical properties of the composites.

show abstract

“…En el ámbito de los materiales carbonosos se han realizado estudios con microondas especialmente para la sínte-sis de nuevos materiales [12], nanoestructuras de carbono [13,14,15], carbones grafíticos [16], soportes carbonosos de catalizadores [17], xerogeles de carbono [18], entre otros; también para la preparación [16,19,20,21], modificación [22] y regeneración de carbones activos [23,24,21], con implementación comercial en algunos casos, como ocurre con la regeneración del carbón activo utilizado en la Industria de extracción de oro [25]. Por otro lado, los procesos asistidos con microondas han facilitado la molienda de carbones [11], así como su desulfuración [26].…”

Section: Introductionunclassified

Variables influyentes en el secado discontinuo del carbón asistido con microondas

Alvarado

2014

prospect

View full text Add to dashboard Cite

RESUMENEn este estudio se evalúa la influencia del tamaño de partícula, el tipo de carbón, el tiempo de operación y la energía microondas suministrada como variables influyentes en el proceso de secado del carbón mineral. Posteriormente, se compara el secado con microondas con el secado térmico del carbón en estufa convencional. Los resultados evidencian que con el secado en horno microonda se remueve hasta el 50% de la humedad contenida en el carbón en el 10% del tiempo requerido por la técnica convencional. Se encontró que el proceso microondas no afecta las propiedades de Índice de Hard Grove, poder calorífico y contenido de ceniza del carbón bajo las condiciones empleadas en esta investigación. ABSTRACTThis study evaluates the variables effect of particle size, coal type, operating time and microwave power level during the coal dewatering in a batch microwave process. The batch microwave coal drying was obtained at 300 and 500W of power and was compared with the muffle thermal drying at 80°C. The results show that batch microwave drying is able to remove the 50% of the contain moisture within the coal delaying 10% of the required time by muffle technique. Was found that microwave process do not affect Hard Grove Index, the Calorific Value, and the Ash content coal properties.

show abstract

Microwave drying as an effective method to obtain porous carbon xerogels

Cited by 39 publications

References 7 publications

Designing Nanostructured Carbon Xerogels

Designing Nanostructured Carbon Xerogels

The effect of catalyst and heat treatment on the properties of carbon–metal composites

Variables influyentes en el secado discontinuo del carbón asistido con microondas

Contact Info

Product

Resources

About