Borik Asit ve Boraks Pentahidrat Kristalleri için Kekleşmenin İncelenmesi

Abstract

Bu çalışmada, CMSMPR (sürekli-karıştırmalı, sürekli-ürün çekmeli) tipi kristalizörde, saf ortamda üretilen borik asit ve boraks pentahidrat kristallerinin su alma yeteneği, kekleşme derecesi tayini, ve mekanik dayanım, kekleşme, kırma testleri yapılmıştır. CMSMPR sisteminde üretilen hem borik asit hem de boraks pentahidrat kristallerinin su alma yeteneği, kekleşme, aşınma derecelerinin yüksek olduğu ve bu kristallerin nemden oldukça etkilendiği ve bu nedenle habitinde bozulmalar meydana geldiği görülmüştür. Ayrıca, kekleşme ve kırma testleri sonucunda belirlenen akışkanlık durumları değerlendirildiğinde ise borik asit kristallerinin kohezif (yapışan), boraks pentahidrat kristallerinin ise çok kohezif olduğu tespit edilmiştir. Tüm bu sonuçlar esas alındığında, kekleşmeyi önlemek için borik asit ve boraks pentahidrat kristallerinin yüksek nem oranlarına maruz kalmaması gerektiği görülmektedir.

Keywords

• Boraks Pentahidrat,Borik Asit,Kristalin kekleşmesi

Investigation of Caking for Boric Acid and Borax Pentahydrate Crystals

Abstract

In this study, the determination of hygroscopicity and the caking degree, and the tests of mechanical strength, caking, breaking of boric acid and borax pentahydrate crystals produced in pure medium in the CMSMPR (Continuous Mixed-Suspension, Mixed-Product Removal) type crystallizer were performed. Both the boric acid and borax pentahydrate crystals produced in the CMSMPR system were found to have high hygroscopicity, degrees of caking and attrition, and these crystals were highly influenced by moisture and thus deteriorated their habit. Furthermore, when the fluidity conditions determined as a result of caking and breaking tests were evaluated, it was found that boric acid crystals were cohesive and borax pentahydrate crystals were very cohesive. Based on these results, it is seen that boric acid and borax pentahydrate crystals should not be exposed to high humidity in order to avoid caking.

Keywords

• Borax Pentahydrate,Boric Acid

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