scholarly journals Kaolinite-Magnesite Based Ceramics. Part I: Surface Charge and Rheological Properties Optimization of the Suspensions for the Processing of Cordierite-Mullite Tapes

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 757 ◽  
Author(s):  
Aghiles Hammas ◽  
Gisèle Lecomte-Nana ◽  
Nadjet Azril ◽  
Imane Daou ◽  
Claire Peyratout ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Sodium Silicate ◽  
Ph Value ◽  
Tape Casting ◽  
Casting Process ◽  
Sodium Hexametaphosphate ◽  
Cohesion Energy ◽  
Limit Values ◽  
Clay Slurry ◽  
Kaolinitic Clay

The present study aimed at investigating the influence of the concentration of sodium silicate and sodium hexametaphosphate on the dispersion of an aqueous kaolinitic clay slurry regarding further use for the tape casting process. The zeta potential of the kaolinitic clay slurry matched the requirements for tape casting. The addition of magnesite in the kaolinitic slurries tended to increase the zeta potential towards the required limit values. Despite this, the further addition of surfactants allowed improving the zeta potential in agreement with the tape casting conditions. Accordingly, the rheological behavior, under continuous and oscillatory flow conditions, of various mixtures of magnesite and a kaolinitic clay was studied. Regarding the pH and the zeta potential measurements, the E–F attraction prevailed at low pH value, and F–F or E–E attraction was predominant at high pH value. All slurries exhibited a shear thinning behavior, which was well-correlated by the Herschel–Bulkley model. It appeared that the best stability for the kaolinitic clay slurries was obtained while using 0.4 mass% and 1.2 mass% of sodium hexametaphosphate and sodium silicate, respectively. An increase in the magnesite concentration above 6 mass% led to a complex behavior with low cohesion energy due to the occurrence of soluble complexes.

scholarly journals Kaolinite-Magnesite Based Ceramics. Part I: Surface Charge and Rheological Properties Optimization of the Suspensions for the Processing of Cordierite-mullite Tapes

2019 ◽  
Author(s):  
Aghiles Hammas ◽  
Gisèle Laure Lecomte-Nana ◽  
Nadjet Azril ◽  
Imane Daou ◽  
Claire Peyratout ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Sodium Silicate ◽  
Ph Value ◽  
Tape Casting ◽  
Casting Process ◽  
Sodium Hexametaphosphate ◽  
Cohesion Energy ◽  
Limit Values ◽  
Clay Slurry ◽  
Kaolinitic Clay

The present study aimed at investigating the influence of the concentration of sodium silicate and sodium hexametaphosphate on the dispersion of an aqueous kaolinitic clay slurry regarding further use for the tape casting process. The zeta potential of the kaolinitic clay slurry matched the requirements for tape casting. The addition of magnesite in the kaolinitic slurries tended to increase the zeta potential towards the required limit values. Despite, the further addition of surfactants allowed improving the zeta potential in agreement with the tape casting conditions. Accordingly, the rheological behavior, under continuous and oscillatory flow conditions, of various mixtures of magnesite and a kaolinitic clay was studied. Regarding the pH and the zeta potential measurements, the E–F attraction prevailed at low pH value, and F–F or E–E attraction was predominant at high pH value. All slurries exhibited a shear thinning behavior, which was well-correlated by Herschel–Bulkley model. It appeared that the best stability for the kaolinitic clay slurries was obtained while using 0.4 mass% and 1.2 mass% of sodium hexametaphosphate and sodium silicate respectively. An increase in the magnesite concentration above 6 mass% led to a complex behavior with low cohesion energy due to the occurrence of soluble complexes.

Fabrication and Characterization of Sr0.7Ca0.3TiO3 Substrates Using Aqueous Tape Casting Process

2010 ◽  
Vol 434-435 ◽  
pp. 275-277
Author(s):  
Wei Liang Liu ◽  
Shuo Qi Liu ◽  
Du Song Mao
Keyword(s):  
Zeta Potential ◽  
Ph Value ◽  
Tape Casting ◽  
Casting Process ◽  
Solid Loading ◽  
Potential Measurement ◽  
Binder Ratio ◽  
Rheological Test ◽  
Test Result

Sr0.7Ca0.3TiO3 (SCT) substrates were prepared through aqueous tape casting. Properties of SCT slurries with and without ammonium polyacrylate (NH4PAA) dispersant were characterized by zeta potential. The zeta potential measurement result shows that the isoelectric point (IEP) of the powder changed obviously with the addition of the dispersant. The optimum pH value of the slurry is in the range of 9-10. The rheological test result indicates that the proper content of the dispersant is between 0.6 and 0.8 wt%. The effect of different plasticizer/binder ratio (R) on the properties of the green tapes was investigated. For 56 wt% solid loading, the tensile strength of the green tape reached 2.02 MPa and the breaking elongation rate was about 8%. SEM micrographs show that the microstructure of the green tapes is homogeneous and the microstructure of the sintered tapes is dense.

scholarly journals EFFECT OF PH CONDITIONS ON GOETHITE BEHAVIOR IN THE PRESENCE/ABSENCE OF DIFFERENT DISPERSANTS

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Svjetlana Sredić ◽  
Ljiljana Tankosić
Keyword(s):  
Zeta Potential ◽  
Surface Charge ◽  
Sodium Silicate ◽  
Ph Value ◽  
Sodium Hexametaphosphate ◽  
Surface Charges ◽  
Effect Of Ph ◽  
Ph Values ◽  
Ph Conditions ◽  
Settling Behavior

Dispersion and settling behavior of goethite has been studied and effect of pH values on surface properties of goethite particles with /without dispersants has been discussed. A prerequisite for the successful flocculation is the stabilization of the system which is achieved by the good dispersion of particles. The effect of pH, sodium silicate (Na2SiO3), sodium hexametaphosphate (Na6P6O18) and sodium pyrophosphate (Na4P2O7), on the surface charges of goethite was studied. The IEP of natural goethite was found by measuring zeta potential at pH value of 6.6. With the use of sodium silicate the IEP of goethite moves to pH 4.95. An IEP could not be detected when the poly-phosphates were used and the surface charge is negative from pH 2 to pH 12. The relatively high zeta potential values indicate a fairly stable dispersion, especially when the sodium hexametaphosphate were used as dispersant.

scholarly journals Kaolinite-Magnesite or Kaolinite–Talc-Based Ceramics. Part II: Microstructure and the Final Properties Related Sintered Tapes

Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1080
Author(s):  
Aghiles Hammas ◽  
Gisèle Lecomte-Nana ◽  
Imane Daou ◽  
Nicolas Tessier-Doyen ◽  
Claire Peyratout ◽  
...  
Keyword(s):  
Flexural Strength ◽  
Ceramic Industry ◽  
Raw Materials ◽  
Tape Casting ◽  
Casting Process ◽  
Aqueous System ◽  
Mechanical And Thermal Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Kaolinitic Clay

In recent decades, talc and kaolinite have been widely used as raw materials for the ceramic industry. In this study, the final characteristics of kaolinitic clay mixed with 6 mass% of magnesite obtained in our previous work were compared with those obtained with mixtures of kaolin (kaolin BIP) and talc (as the source of magnesium oxide). However, different amounts of talc in the kaolin powder were studied, namely 10, 30, and 50 mass% of added talc (with respect to kaolin + talc). The tape casting process was used during this work in order to manufacture the green tapes in an aqueous system with 0.2 mass% of dispersant. Subsequently, the green tapes were heated to 1000 and 1100 °C with a dwelling time of 12 min. The green and sintering tapes were characterized using the following techniques: DTA/TG, X-ray diffraction, porosity, and flexural strength analyses. The results obtained from our previous work indicate that the specimen with 6 mass% of MgCO3 sintered at 1200 °C for 3 h exhibited the best performances, with high flexural strength and weak porosity value—117 MPa and 27%—respectively. As results from this study, the optimal mechanical and thermal properties of sintering tapes were obtained for the specimen with 10 mass% of added talc sintered at 1100 °C. Indeed, this specimen exhibited 50 MPa and 43% of stress to rupture and apparent porosity, respectively.

scholarly journals The Flotation Separation of Magnesite and Limonite Using an Amine Collector

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Jiahong Han ◽  
Xiaoan Li ◽  
Shujuan Dai ◽  
Guozhen Liu
Keyword(s):  
Infrared Spectroscopy ◽  
Zeta Potential ◽  
Sodium Silicate ◽  
Carboxymethyl Cellulose ◽  
Sodium Carboxymethyl Cellulose ◽  
Sodium Hexametaphosphate ◽  
Electrostatic Adsorption ◽  
Adsorption Mechanisms ◽  
The Difference ◽  
Soluble Components

In order to reduce the iron impurities in magnesite ore and improve the purity of magnesium products, the difference in floatability between magnesite and limonite has been studied by using mixtures with a collecting agent—KD (cationic amine collectors, containing soluble components). Sodium hexametaphosphate, pH, sodium silicate, and sodium carboxymethyl cellulose were used as regulators. Adsorption mechanisms of the reagents on minerals were analyzed by a zeta potential analyzer and infrared spectroscopy. Sodium silicate increased the floatability of both minerals at 11.6. All the three regulators reduced the zeta potential of both minerals, while KD increased the zeta potential of magnesite and decreased the zeta potential of limonite. All the three regulators were likely chemically adsorbed on the surface of both minerals; KD has electrostatic adsorption on the surface of the minerals.

On the Factors Influencing the Liquidity of Slip Casting Al2O3 Slurry

2016 ◽  
Vol 680 ◽  
pp. 115-119
Author(s):  
Zhen Hua Geng ◽  
Kai Li ◽  
Ping Wu ◽  
Hai Jian Li
Keyword(s):  
Zeta Potential ◽  
Mass Fraction ◽  
Ph Value ◽  
Solid Phase ◽  
Slip Casting ◽  
Casting Process ◽  
Test Results ◽  
Absolute Value ◽  
Layer Effect ◽  
Potential Test

Abstract: This paper use zeta potential test and dynamic viscosity test to research the influence of different factors such as pH value, mass fraction of solid phase and dispersant content on the liquidity of Al2O3 slurry. The test results show that, when the solid-phase mass fraction and particle size are given, the absolute value of zeta potential increases with the rise of pH value, raise at first then descrease with the adding of (NaPO3)6. This article analyzes the phenomena from a legal point of electric double layer effect. The results of liquidity test are consistent with zeta potential test. The optimum value of pH value, mass fraction of solid-phase and dispersant content are determined by formulation design. The study develop a Al2O3 slurry with high fluidity which has an important significant in slip casting process of Al2O3 ceramics.

A Study of Slurries in Aqueous Tape Casting Processing

2007 ◽  
Vol 280-283 ◽  
pp. 753-756
Author(s):  
Xue Min Cui ◽  
Yong Huang ◽  
Ji Zhou ◽  
Chang An Wang ◽  
Shi Xi Ouyang
Keyword(s):  
Coating Thickness ◽  
Ph Value ◽  
Tape Casting ◽  
Casting Process ◽  
Solid Loading ◽  
Binder System ◽  
Drying Process ◽  
Rheological Behaviors ◽  
Acrylic Latex ◽  
Slurry Coating

As a good binder for aqueous Al2O3 suspensions tape-casting process, a commercial styrene-acrylic latex binder had been investigated. This paper studied on the rheological behaviors of the suspensions and drying process of aqueous slurries with latex binder system, and the research results indicated the rheological behaviors was affected by pH value, solid loading and dispersant (PAA-NH4) additives; and the drying speed of slurries was most decided by drying temperature and slurry coating thickness.

Research on the Floatability of Magnesite and its Gangue Minerals with Sodium Oleate and Lauryl Amine as Collectors

2013 ◽  
Vol 798-799 ◽  
pp. 328-332 ◽  
Author(s):  
Jin Yao ◽  
Ying Hou ◽  
Yu Lian Wang ◽  
Wen Xing Zhong ◽  
Wan Zhong Yin
Keyword(s):  
Sodium Silicate ◽  
Sodium Oleate ◽  
Ph Value ◽  
Sodium Hexametaphosphate ◽  
Mineral Flotation

In this study, the single mineral flotation experiments of magnesite and its associated minerals including dolomite, serpentine, talc and quartz were conducted, and the influences of the dosage of collectors such as sodium oleate and lauryl amine, pH value and the influences of regulars such as sodium hexametaphosphate and sodium silicate on those minerals were researched. According to the results, a process to reduce the content of gangue minerals was proposed, which at first use lauryl amine as a collector to remove most talc and quartz and part of the dolomite and serpentine, and then use sodium oleate as a collector to separate magnesite from dolomite and serpentine. This is a theoretical reference for the beneficiation of magnesite.

scholarly journals Microstructure and Thermoelectric Properties of (Bi0.48Sb1.52)Te3 Thick Films Prepared with Tape Casting Method

Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 140
Author(s):  
Lichen Liu ◽  
Ziping Cao ◽  
Min Chen ◽  
Jun Jiang
Keyword(s):  
Thermoelectric Properties ◽  
Low Cost ◽  
Thick Films ◽  
Tape Casting ◽  
Casting Process ◽  
Casting Method ◽  
Glass Substrates ◽  
Conductive Films ◽  
Casting Technology

This paper reports the fabrication and characterization of (Bi0.48Sb1.52)Te3 thick films using a tape casting process on glass substrates. A slurry of thermoelectric (Bi0.48Sb1.52)Te3 was developed and cured thick films were annealed in a vacuum chamber at 500–600 °C. The microstructure of these films was analyzed, and the Seebeck coefficient and electric conductivity were tested. It was found that the subsequent annealing process must be carefully designed to achieve good thermoelectric properties of these samples. Conductive films were obtained after annealing and led to acceptable thermoelectric performance. While the properties of these initial materials are not at the level of bulk materials, this work demonstrates that the low-cost tape casting technology is promising for fabricating thermoelectric modules for energy conversion.

Sign in / Sign up

Export Citation Format

Share Document