Micro-Fabric Transformations of Ball Clay in Alkaline Environment

Based on the strong evidence of case histories, this study focused on mineralogical and morphological changes of an artificial kaolinitic soil -Ball clay, when exposed to different concentrations of sodium hydroxide (0.1N, 1N, 4N, and 8N) under different curing periods (7, 28 and 100 days). Sediment volume tests are conducted on Ball clay with all combinations and results are analyzed with the help of analytical techniques. XRD and SEM studies are analyzed to understand the micro-level changes of alkali contaminated Ball clay. Mineralogical and morphological transmutations of Ball clay are investigated for 7, 28, and 100 days curing period. Results revealed new mineral formations like Sodalite under 4N and 8N concentrations of NaOH with 100 days interactions are well observed. The morphological transformation from needle shape to pellet shape is clear evidence of the rate of dissolution and precipitation of minerals under 100 days curing periods.

Micro- and Nanotexture and Genesis of Ball Clays in the Lower Cretaceous (SE Iberian Range, NE Spain)

Ball clay deposits in the SE of the Iberian Range (NE Iberian Peninsula) consist of Albian clays and siltstones with greyish and blackish colors, interbedded with subbituminous coals. The ball clays are nowadays mined for the manufacture of white color ceramics. The mineralogy of these deposits consists mainly of kaolinite, illitic phases, and quartz. The euhedral to sub-euhedral morphology of the kaolinites suggests their in-situ origin. The anhedral morphology of the illites and the presence of frayed illites suggest a detrital origin. At the micro-scale, authigenic kaolinite booklets are observed filling pores and forming mica/kaolinite intergrowths, in which the kaolinite grows between the cleavage sheets of pre-existing detrital mica. At nanometer scale, illite/smectite (IS) phases are detected forming interlayers with mica and kaolinite, and evidence of the replacement of mica by kaolinite is observed. The matrix consists of defective illite and kaolinite, and random mixed layers of kaolinite-I/S (Kln-IS), illite-I/S (Ilt-IS), and I/S-smectite (IS-S). The textures of illite and the presence of different types of mixed layers suggest that the expandable phases and kaolinite are products of mica alteration. The effectivity of the alteration was probably a consequence of the low pH that occurred in the environment due to the presence of abundant organic- and acidic- rich fluids.

Potential utilization of quartz sand and kaolin from tin mine tailings for whitewares

Purpose. To do experimental research into the potential utilization of residual quartz-based sands and kaolin from the tin mine tailings in Bangka Belitung Province, Indonesia. Methods. Process of raw materials beneficiation by washing, vibration on the screen, magnetic separation. Manufacturing whiteware from beneficiated quartz sand, beneficiated kaolin, ball clay and feldspar. The whiteware properties were analyzed in terms of shrinkage, water absorption, flexural strength, and whiteness index. Findings. The amount of iron oxide in the quartz sand and the kaolin was reduced by beneficiation process from 1.12% and 1.06 to 0.51% and 0.5%, respectively. The whiteware specimens showed the required physical and mechanical properties. Thus, these raw materials can principally be utilized for the manufacture of whiteware ceramic items with whiteness index up to 68.3. Originality. Quartz sand and kaolin extracted from tin mine tailings were used after beneficiation of raw materials for whiteware manufacture. Practical implications. This research can provide practical solution to the problem related to mine tailings rich in quartz and kaolin which can be utilized for manufacturing whiteware. Keywords: tin mine tailings, quartz sand, kaolin, magnetic separation, whiteware ceramics

Scaffolds Materials from Gellan Gum Incorporated Ball Clay as Dressing Materials

The demand for wound management treatment especially advanced and active wound care products is huge. In this study, the scaffolds were prepared from gellan gum (GG) incorporated ball clay (BC) at different concentrations to investigate their swelling properties, water vapor transmission rates (WVTR), mechanical characteristic and thermal behavior. There are three different concentrations of BC were added into the GG scaffolds which were 5% w/w (GG/BC5), 10% w/w (GG/BC10) and 15% w/w (GG/BC15). Swelling ratio of GG scaffolds were increased upon addition of ball clay, while WVTR values of all scaffolds were decreased in the range of 1081–1164 g m−2 d−1. The mechanical performance results show that the GG/BC10 has the highest compressive stress at break (26 ± 5 MPa) and compressive strain at break (110 ± 21%). For thermal behavior, it shows that the thermal stability of GG scaffolds had improved after the addition of ball clay attributed to the interaction between GG and ball clay. The results show that the GG/BC scaffolds could be a potential candidate to be used as an active wound care product.

Sayong Ball Clay Membrane for Copper and Nickel Removal from Effluent

An adsorption filtration mechanism using porous ceramic membranes was proposed for the removal of heavy metals from the effluent of the UTM Lake. The effectiveness of the removal depends on kaolinite microparticle which is used as an adsorption agent in ceramic membranes. In this work, Sayong ball clay (SBC) from Malaysia was used in the preparation of the ceramic membrane. Sayong ball clay membranes were fabricated by gel casting (GC) and spark plasma sintering (SPS) methods. The effect of kaolinite and pore size on copper and nickel removal was investigated. X-ray fluorescence (XRF), X-ray diffraction (XRD), mercury porosimetry, and adsorption analysis were used to relate with the adsorption performance. It is found that kaolinite with the 14:1 ratio of monomers in the GC-SBC membrane performed the highest heavy metal removal.