Effect of particle-size and pore-size distributions in cross-flow filtration

In this research study, two different wooden biomasses (birch and pine) were thermally carbonized and steam-activated into activated carbons in a one-stage process. The effects of particle size and humidity (as received and oven-dried) on the properties, such as specific surface areas, pore volumes, and pore size distributions, of the final activated carbon characteristics were examined. Another set of biomasses (birch, spruce, and pine) was pre-treated before carbonization and the activation steps through an extractive process using a weak acetic acid in Soxhlet extractors. According to the results, the dried samples had a slightly lower surface area, while no difference was observed in the yields. For the extracted samples, there was a significant difference, especially in the pore size distributions, compared to the non-extracted samples. There appeared to be a shift from a meso-microporous distribution to a microporous distribution caused by the extractive pre-treatment.

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Cross-flow Filtration through Ceramic Membranes of Enzymes and Degradation Products from Enzymatic Peeling of Satsuma Mandarin Segments

Food Science and Technology International ◽

10.1177/1082013208094681 ◽

2008 ◽

Vol 14 (5_suppl) ◽

pp. 71-76 ◽

Cited By ~ 4

Author(s):

M. Moliner ◽

D. Saura ◽

J.M. Ros ◽

J. Laencina

Keyword(s):

Molecular Weight ◽

Pore Size ◽

Degradation Products ◽

Cross Flow ◽

Ceramic Membranes ◽

Satsuma Mandarin ◽

Cross Flow Filtration ◽

Enzymatic Peeling ◽

Commercial Enzymes ◽

Flow Filtration

The present work evaluates the possibility of using cross-flow filtration to recover enzymatic activities from commercial enzymes used for peeling mandarin segments. Two ceramic membranes of different pore size and molecular weight cut-off were assayed. The membrane of 40 kDa molecular weight cut-off provided better separation of enzymes and carbohydrates than the membrane of 0.14 μm pore size, since the enzymes were readily retained in the retentate fraction, while carbohydrates easily passed into the permeate fraction. After separation, both fractions (enzymes and carbohydrates) could be further used.

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Relationship between pore size distributions and physical properties of clay soils

Soil Research ◽

10.1071/sr9740107 ◽

1974 ◽

Vol 12 (2) ◽

pp. 107 ◽

Cited By ~ 18

Author(s):

ID Sills ◽

LAG Aylmore ◽

JP Quirk

Keyword(s):

Particle Size ◽

Pore Size ◽

Pore Volume ◽

Total Pore Volume ◽

Particle Size Analysis ◽

The Other ◽

Clay Soils ◽

Size Analysis ◽

Size Distributions ◽

Pore Size Distributions

Pore size distributions using mercury injection and nitrogen sorption techniques were determined on a number of soils classified as clays on the basis of particle size analysis. Some of these soils exhibit markedly different consistencies during texturing and undergo changes in texture during prolonged manipulation, e.g. subplastic, superplastic and self-mulching soils. The pore size distributions for these soils do not differ significantly from those obtained for the normal labile clay soil in the pore size range 2 nm to 50 �m. The clay soils examined, with the exception of the krasnozem, have the majority of their pore volume within pores smaller than 10 nm with the predominant pore size centred around 3 nm plate separation. In the case of the krasnozem, the particle size analysis does not correspond to the texture assessment as a clay loam. Surface and subsoil samples of the krasnozem have high porosities and predominant plate separations of 6 nm. They consequently possess significantly different pore size distributions from the other clays. In the case of the surface sample, only a small proportion of its total pore volume is in pores smaller than 10 nm. These differences in pore structure observed between the krasnozem and the other soils examined may result from differences in mineralogy, and in particular from the high sesquioxide content of the krasnozem.

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Cross-flow ultrafiltration of proteins through asymmetric polysulfonic membranes: I. Retention curves and pore size distributions

Biotechnology and Bioengineering ◽

10.1002/bit.260470602 ◽

1995 ◽

Vol 47 (6) ◽

pp. 617-625 ◽

Cited By ~ 16

Author(s):

P. Prádanos ◽

A. Hernández

Keyword(s):

Pore Size ◽

Cross Flow ◽

Size Distributions ◽

Pore Size Distributions

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Glasses and Ceramics from Colloids

MRS Proceedings ◽

10.1557/proc-32-205 ◽

1984 ◽

Vol 32 ◽

Cited By ~ 2

Author(s):

G. W. Scherer

Keyword(s):

Particle Size ◽

Pore Size ◽

High Purity ◽

Low Temperatures ◽

Solvent Evaporation ◽

Nonpolar Solvent ◽

Size Distributions ◽

Pore Size Distributions ◽

The Mean

ABSTRACTFlame-generated particles can be suspended in a nonpolar solvent, molded, and gelled. The microstructure obtained after solvent evaporation depends on the characteristics of the colloid. Higher solids loadings lead to denser green bodies and narrow pore size distributions. The mean pore size is proportional to the particle size. Sintering occurs at relatively low temperatures, producing amorphous or crystalline bodies of high purity.

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