Description

Brief Overview

Borax pentahydrate, also known as Etibor 48 or sodium tetraborate pentahydrate, is the most common form of sodium borate used in various industries. It is a white, odorless crystalline granular or powder product that is mildly alkaline both alone and in solution. Compared to Borax Decahyrdate, which is physio-chemically comparable, Etibor 48 has a higher Boron content per unit mass, a lower ratio of bound water and is less hygroscopic.

Manufacturing Process

High-purity sodium tetraborate pentahydrate is produced by:

(a) Reacting the mineral colemanite (2CaO·3B 2 O 3 .5H 2 O) with sodium carbonate (Na 2 CO 3 ) in an aqueous environment to produce an aqueous solution of sodium tetraborate and sodium hydroxide, with precipitation of solid calcium carbonate;

(b) Treating the aqueous solution obtained in stage (a), after separating the precipitated calcium carbonate, with boric acid (H 3 BO 3 ) to neutralize the sodium hydroxide and form a further quantity of sodium tetraborate;

(c) Separating sodium tetraborate pentahydrate by crystallization from the aqueous solution obtained in stage b.