ORTHO-BORIC ACID.

 SYNONYMY: ORTHO-BORIC ACID.
 FORMULA: BO3H3.
 MOLECULAR WEIGHT: 61,84.
 CRISTALIZATION: it crystallizes in tryclinium-pinacoidal scales.
 FUSION POINT: 170º C.
 RELATIVE DENSITY: 1,435 to 15º C.
 DISSOLVING HEAT: - 5400 cal/mol at 18º C.  pH of SOLUTIONS: at 20º C.

Conc.	pH	Conc.	pH.
0,1 %	6,1	3,0 %	4,2
0,5 %	5,6	4,0 %	3,9
1,0 %	5,1	4,7 %	3,7
2,0 %	4,5

 CENTESIMAL COMPOSITION:      B2O3 = 56,3 %     H2O = 43,7 %.
 TABLE OF SOLUBILITY: Grams per every 100 grams of water.

Tº C	Grams	Tº C.	Grams
0	2,52	60	12,97
10	3,49	70	15,75
20	4,72	80	19,10
30	6,23	90	23,27
40	8,08	100	27,53
50	10,27	103,3	29,27

• These solubilities are influenced by the presence of other substances. For example, sodium chloride, lithium chloride and mineral acids reduce solubility, whereas sodium sulfate, sodium nitrate, potassium nitrate, potassium sulfate and potassium chloride increase it.

 EFFECTS OF HEAT: in closed environments, it melts at 171º C. In open environments, heat above 100º C causes a gradual water loss, going successively from meta-boric acid (HBO2), and tetra-boric acid (H2B4O7), to ultimately reach boric anhydride (B2O3), which melts at 450º C.
 STABILITY: it is stable at room temperature and is either volatized by water vapor or dragged by it without decomposing.
 BORIC ACID USES:

• GLASS INDUSTRY: Boric silicates and thermal glass used for laboratory material, tubes, glasses, thermometers, etc. Also used for heat-resistant cooking utensils such as oven trays and those exposed to direct flame such as milk pots and coffeepots. Automobile lights. Lenses for bright signs and traffic lights. Lenses for glasses, photographic, cameras, telescopes, microscopes, etc.
  Glass fiber used as thermal and acoustic insulator.
  
• ENAMELS: Manufacturing of long-lasting, easy-to-wash hard surfaces, such as those found in cooking stoves, washing machines, refrigerators, bath tubs, heaters, ovens, street name plates, etc.
• FRIED ENAMELS: vitreous enamel for the ceramics industry: glazed ceramics, floor tiles. Roof tiles, etc.
• CHEMICAL BY PRODUCTS: Fluoro-borate, borate fluorine, boric alloys, boric carbon, ferroboron, etc. Boron hydride, borons, di-borons, boronic acids, borazines, etc.
• FRUIT GROWING: citrus washing and conservation.
• FUNGICIDES.
• COSMETICS AND PHARMACEUTICALS: Creams, lotions and facial powders, toothpaste, deodorants, shampoo, eye solutions, medicines.
• COLOR STABILIZERS.
• NON-FERROUS METAL REFINING: Chromium, Nickel, Copper, Lead, Aluminum, etc.
• INSECT SPRAYS.
• TANNING: finishing touches on leather and fur.
• TEXTILE INDUSTRY: finishing touches on fabrics.
• MEAT CONSERVATION.
• FIREPROOF PRODUCTS: fireproof protection of theater curtains, wall paper, fireproof suits, etc.
• PAINTS: latex-based paints.

 STANDARD ASSAY: Boric acid has the following specification:

B2O3	=	56,00	% minimum
H20	=	43,50	%
SO4	=	0,15	% maximum
CI	=	0,10	% maximum
Fe	=	0,0015	% maximum (p.p.m.)
Humidity	=	0,10	% maximum
Total H3BO3	=	99,50	% minimum

 PRESENTATION: Boric Acid comes in different degrees of granulation, namely
(in Tyler Mesh):

Retained 12	0,00 %
Retained 18	0,25 %
Retained 20	0,84 %
Retained 30	3,65 %
Retained 40	5,83 %
Retained 50	14,23 %
Retained 80	33,40 %
Passes 80	41,65%

Granulation can be adjusted to meet special requirements.
The product is packaged in double polyethylene / polysterene 25-kg bags or in 1000-kg Big Bags. A 20-ton container loads 21 tons of boric acid in 25-kg bags.