The crystallisation of Alkaline-earth Metal Tungstates from solutions in Sodium Tungstate Melts

Kerja ini mengemukakan suatu kajian mengenai penghabluran Tungstat logam Alkali-Bumi dari larutan lebur Natrium Tungstat. Keterlarutan Garam-Garam logam Alkali-Bumi pada suhu-suhu yang berbeza antara 600° ke 1200°C telah didapati dari bahan bacaan yang tertentu. Kajian kuantitatif peringkat awal...

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Bibliographic Details
Main Author: Subramaniam, Appalasami
Format: Thesis
Language:English
Published: 1977
Subjects:
Online Access:http://eprints.usm.my/35333/1/APPALASAMI_SUBRAMANIAM_%28KHK%29_%28NN24%29.pdf
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Summary:Kerja ini mengemukakan suatu kajian mengenai penghabluran Tungstat logam Alkali-Bumi dari larutan lebur Natrium Tungstat. Keterlarutan Garam-Garam logam Alkali-Bumi pada suhu-suhu yang berbeza antara 600° ke 1200°C telah didapati dari bahan bacaan yang tertentu. Kajian kuantitatif peringkat awal mengenai penghabluran Titanat Logam Alkali-Bumi dibuat dengan cora penyejukan perlahan yang berterusan kepada larutan tepu lebur Logam Klorid Alkali-Buml dart suhu pengabl.wan awtd, T~ = 1000° ke 1200°C, ke takat suhu ambien. Kesan suhu penghabluran awol dan keterlarutan zat laruton suhu penghabluran awal(soling tindakon zat larutan-pelarut) dan kadarcepat penyejukan atas bentuk hablur ohkir dikaii. Hastl kojion ini dibanding dengon hasil kojion peringkat awol mengenai penghobluran Tungstat Logam Alkali-Bumi dengan cora penyejukan perlahan berterusan kepada larutantepu lebur Tungstat Natrium dari suhu-suhu penghabluran awal, T 0 = 800 ke 1000 C, ke takat suhu ambien. Tungstat Natrium digunakan sebagai pelarut yang sesuai bagi penghabluran Tungstat Logam Alkali~Bumi dalam lingkungkan bezantara suhu T 0 = 800° ke 1000°C dan kadar-kadar penyejukan RT = 40° ke 200° C sejam. This work presents a study of the crystallisation of Alkaline-earth Metal Tungstates from solutions in Sodium Tungstate Melts. The solubilities of the Alkaline-earth Metal Salts in Sodium Tungstate at various temperatures from 600° to 1200° C were obtained from the I i terature • Preliminary quantitative studies were made on the crystallisation of Alkaline-earth Metal Titanates by slow continuous cooling of saturated solutions in Alkaline-earth Metal Chloride Melts from initial crystallisation temperatures, T0 = 1000° to 1200° C, down to ambient temperature. The effects of initial crystallisation temperature and solute solubility at the initial crystallisation temperature (solute-solvent interaction) and the rate of cooling on the final crystal form and size were investigated. These results were compared with the results of the preliminary studies on the crystallisation of Alkaline-earth Metal Tungstates by slow continuous cooling of saturated solutions in Sodium Tungstate Melts from initial crystallisation temperatures, T0 = 800°to 1000° C, down to ambient temperature. Sodium Tungstate was a suitable solvent for crystallisation of the Alkaline-earth Metal Tungstates within the temperature range T0 =8000 to I000°C and rates of cooling RT = 40° to 2000C/hr.