Manufacture of boron-containing compound using cotton balls hydrothermal method and its comprehensive utilization

Abstract

The invention provides a boron-containing compound prepared by ulexite hydrothermal method and the synthetic utilization thereof. And the raw material is 80-200 mesh ulexite or probertite powder containing B2O3 >=37.5 wt%, which is prepared into calcium borate product and sodium polyborate solution containing B2O3 >=40wt% and Na2O >=0.5wt%, meeting alkali free glass and boron-containing raw material requirements; synthetically utilizing the sodium polyborate solution, evaporating and concentrating, cooling and crystallizing without adding in sodium- containing alkali or salt, so as to be able to prepare borax product; adding less sulphuric acid into borax mother liquor after crystallization and separation processing to be able to prepare boric acid; adding CaO or Ca(OH)2 into the borax mother liquor or sodium-containing polyborate with borax to be able to prepare purer calcium metaborate and simultaneously sodium metaborate by-product.

Description

technical field

[0001] The invention relates to a hydrothermal method for producing calcium borate, borax, boric acid and sodium metaborate by comprehensively utilizing boronite in the field of chemical industry. Background technique

[0002] Soda limestone (Na 2 O 2CaO 5B 2 O3) can be directly used in glass industry and ceramic industry as boron-containing raw material, but due to containing Na 2 O, which limits the scope of its direct use.

[0003] As an important raw material for the manufacture of boric acid and borax, soda limestone can be decomposed with sulfuric acid to obtain boric acid according to the following reaction:

[0004] <chemistry num="001"> <chem file="200610046666_cml001.xml" / > < / chemistry> (n=10 or 16)

[0005] Borax can be prepared according to the following reaction:

[0006] <chemistry num="002"> <chem file="200610046666_cml002.xml" / > < / chemistry>

[0007] Known by above-mentioned reaction formula, a...

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