Product properties of 1-amino-8-naphthol-3,6-disulfonic acid monosodium salt

1-amino-8-naphthol-3,6-disulfonic acid monosodium salt (1-amino-8-naphthol-3,6-disulfonic acid monosodium salt), also known as H acid mono sodium salt , 8-Amino-1-naphthol-3,6-disulfonic acid monosodium salt, molecular formula is C ₁₀ H ₈ NNaO ₇ S ₂ , molecular weight is 341.
29, structural formula is

1.
Product performance

White or off-white needle-like crystals; hardly soluble in water, easily soluble in hot water, soluble in alkali solution, slightly soluble in ethanol and ether ; brown-red in reaction with ferric chloride , acidic salt with blue-red fluorescence, add alkali Then it becomes reddish purple, and it is dark green when dissolved in alkaline solution
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2.
Production principle

Naphthalene and fuming sulfuric acid are carbonized and then nitrated, and the nitration product is reduced with iron powder to obtain 1-naphthylamine-3,6,8-sodium trisulfonate (or 1-amino-3,6,8-forbidden trisulfonic acid) Sodium, Koch's Sodium)
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3.
Process flow

4.
Technical formula (kg/t)

5.
Main equipment

Sulfonation pot, nitrification pot, reduction pot, storage tank, filter, alkali fusion kettle, acid precipitation pot, dryer, pulverizer
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6.
Production process

The refined naphthalene is added to a sulfonation pot equipped with cooling, heating and stirring devices, heated to 40°C, and 100% sulfuric acid and 65% fuming sulfuric acid are added for carbonization reaction
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The obtained 1-amino-3,6,8-forbidden trisulfonic acid slurry was dissolved in hot water
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Add 60% sulfuric acid to the acidification pot, heat up to 70°C, add alkali-melted materials within 2 to 3 hours, the feeding temperature is 90 to 95°C, and use Congo red test paper to check the acidity at any time
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