The Ndop plain clayey materials (Bamenda area – NW Cameroon): Mineralogical, geochemical, physical characteristics and properties of their fired products

Abstract

a b s t r a c tThe physicochemical, mineralogical and technological properties of clayey materials from the Ndop plain (NW Cameroon) have been investigated, for their ceramic applications. The clayey materials have mixed facies with colour ranging from brown, grey, mottled and yellowish brown. The thickness of the exploitable clay layer is more than 5 m. Their mineralogical constituents are quartz, kaolinite, illite and feldspars, with kaolinite as major clay mineral. Based on the geochemistry, their source rocks might be felsic, with a mafic rock inference. These materials display high percentage in fine particles and high Atterberg limits. For all the firing temperatures, flexural strength (1.2-11 MPa), water absorption (8.03-24.27%), linear shrinkage (2.10%), weight loss (4.88-16.54%) and bulk density (1.57-2.03 g/cm 3 ) indicate good ceramic properties for firing samples between 900 and 1100 • C. Most of the fired test bricks show a brick red colour with good to very good cohesion. The studied clays were thus, suitable as raw materials for roof tiles, light weight blocks and hollow bricks; however, mixing of high clayey and highly silty materials could improve the quality of the products.

Clay Mineralogy of Brazilian Oxisols with Shrinkage Properties

“…In addition, the value exceeds the kaolinite CEC, which generally has lower values (Giarola et al, 2009;Ryan et al, 2016), indicating a probable contribution of clay minerals with higher negative charge. This medium to high CEC may be a contribution from the 2:1 HIV (hydroxyl-interlayered vermiculite) or HIS (hydroxyl-interlayered smectite) clay minerals and/or a contribution from interstratified kaolinite-smectite in association with kaolinite, as suggested in the literature Teske et al, 2013;Yongue-Fouateu et al, 2016). Dudek and Środoń (2006) found CEC values higher than 100 cmol c kg -1 for pure smectite, and values between 25 and 100 cmol c kg -1 for kaolinite-smectite with less than 10 % of kaolinite layers in the interstratified minerals.…”

“…Traditionally, the presence of broad and asymmetric peaks in the 0.72 and 0.36 nm positions of derivatives basalt soils of southern Brazil has been interpreted as the result of disordered kaolinite, small size crystallites of this mineral (Klug and Alexander, 1954;Wilding and Tessier, 1988;Almeida et al, 2000;Melo et al, 2001), or even dehydrated halloysites (Palmieri, 1986), although some authors also interpret that the asymmetries may be due to the contribution of pure interstratified kaolinite-smectites, or to mixtures of pure smectities with pure kaolinites Teske et al, 2013;Yongue-Fouateu et al, 2016). Starting from the presupposition that asymmetric reflections with values around 0.72 nm were due only to kaolinite, and based on HighScore Plus software, the main crystallographic parameters of this supposed mineral were calculated from the peak positions 0.72 e 0.36 nm for the clay fractions.…”

Study on the Physical and Mechanical Properties of Ancient Clay Brick Samples of Kathmandu Valley, Nepal

“…It is reported that the firing temperature is one of the key factor to modulate the physical, sintering and mechanical properties of different types of brick samples (Ajala et al 2017a(Ajala et al , 2017bVelraj et al 2009;Karaman et al 2006), but not the firing rate on kaolinite based ceramics (Njoya et al 2017). Different physico-sintering properties (i. e., water absorption capacity, apparent porosity, apparent density, bulk density and so on) of clay bricks and their mechanical properties were investigated at different firing temperatures and the brick sample fired at 1100 °C showed the best mechanical properties (Martin-Marquez et al 2010;Ghorbel et al 2008;Yongue-Fouateu et al 2016;Johari et al 2010).…”

Community-Based Approach in the Prevention and Management of Flood Disasters in Babessi Sub-Division (Ndop Plain, North West Cameroon)

“…Nevertheless, this plain attracts many people owing to its fertile alluvial soils resulting from erosion, transport and deposition of materials by streams and rivers as they flood seasonally [21]. Due to demographic pressure, there is the need to farm and inhabit new areas which are prone to floods (especially behind the Bamendjin Dam).…”

“…SRT provides a framework for understanding and exploring how scientific knowledge diffuses in society and can become associated with intergroup power struggles [18] [19]. kaolinite (20% -45%), feldspars (15% -40%), quartz (10% -20%), illite (5% -20%) and traces of smectite, goethite and gibbsite [21]. The alluvial soils (40%) and colluviall soils (35%) occur on the flooded plains, meanwhile hill slopes support lightly evolved soils (12%), andosolic soils (8%) and ferrallitic soils (5%) [22].…”