Properties of Kaolinite as a Raw Material for Porcelain

Abstract

In this work, we investigated kaolinite raw materials from China, Vietnam, and Seongju (Korea) used for the manufacture of porcelain products in Korea. According to chemical analysis results, for the kaolinites from Seongju, more feldspar components containing CaO, K 2 O, and Na 2 O are found than in those from China or Vietnam, of which the composition is close to that of pure kaolinite. Through X-ray Rietveld quantitative analysis, kaolinite and muscovite are found to be the main phases for all the raw materials. Halloysite, quartz, gibbsite, and andesine are found at more than 5% for KM-85 (China), LKC-60 (Vietnam), KC-009 (China), and WA (Seongju). Absorption rate is on order of LKC-60 < KC-009 < KM-85 < PA < WA, and the sample, sintered in reductive atmosphere, exhibits the lowest absorption rate. Comparing the color of the sintered samples, kaolinites of KM-85, LKC-60, and KC-009 (L * : 94-97%) show higher whiteness value than those of WA and PA (L * : 82-91%).

Halloysite in Different Ceramic Products: A Review

“…In a second stage, 25% addition of recycled alumina (silico-aluminous refractory brick waste) in the aforementioned mixture and sintering at 1500 °C further improved the mechanical properties of the new ceramic, especially its flexular strength value (45.08 MPa), due mainly to the high content of mullite which occurred in the refractory waste and its elongated crystal shape. At that time, because of the significant reduction in the kaolin deposits in Korea used in porcelain production, Kim and Hwang [ 55 ] investigated alternative clays derived from China and Vietnam. They indicated that the whole raw materials studied (Korea, China, Vietnam) were comprised mainly of kaolinite and muscovite and less of halloysite, quartz and rutile.…”