Effect of Na2Co3 activation and sedimentation on surface area, particle size, and pore size distribution of Pakistani Ca-bentonite

  • Liaqat Ali ShahEmail author
Original Paper


In this research paper, the purified Na+-bentonite powder was prepared, and its textural characterizations were carried out. Bentonite with 67% montmorillonite, collected from Nowshera region of Khyber Pakhtunkhwa (Pakistan), was taken as a primary sample. The sample was activated with Na2CO3 at the following different mass ratios: 2, 3, 5, and 8%. The activated samples were then purified by sedimentation to eliminate the non-porous minerals. The Na+-bentonite has obtained at 5% Na2CO3 activation as confirmed by the X-ray diffraction. The obtained Na+-bentonite was found free of non-clay minerals. The particle sizes of Na+-bentonite were found considerably smaller in comparison to raw sample. Almost all of the particles were smaller than 4 μm. This seems that the sodium exchange in the activated sample has a valuable impact on its dispersion in aqueous media during particle size measurement. The incredibly high variation in specific surface area, mesopore area/volume, and micropore area/volume were observed after activation. With regard to the mesopore volume/area at smaller pore size, the result of the soda activated sample was found incredibly higher; however, their total pore volume was smaller and total pore area was found about 45% higher. This may be attributed to the high montmorillonite contents and/or the number of layer reduction in tactoids due to interlayer cations replacement by Na+. The higher number of smaller radii pores production, in the case of soda activated sample, results in higher porous structure and the specific surface area which suggest its use as a valuable industrial raw material specifically for the purpose of pharmaceutical and cosmetics, adsorbents, and catalysts.


Porosity Sodium montmorillonite Nowshera district Na2CO3 activation Purification Pakistan 


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Copyright information

© Saudi Society for Geosciences 2018

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of PeshawarPeshawarPakistan
  2. 2.State Key Laboratory of Multiphase Complex Systems, Institute of Process EngineeringChinese Academy of SciencesBeijingChina

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