6654-64-4Relevant articles and documents
Method adopting clean process for preparing H-acid
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Paragraph 0058; 0059; 0060; 0061; 0062, (2016/10/10)
The invention discloses a method adopting a clean process for preparing H-acid. The method comprises the following process: step (10), carrying out extraction treatment on denitrated matter to obtain dilute sulphuric acid and an extracted mixture, and carrying out re-extraction on the extracted mixture to obtain a nitro-T-acid solution; step (20), carrying out reduction treatment on the nitro-T-acid solution obtained in the step (10) to obtain an amino-T-acid solution; step (30), respectively carrying out concentration treatment on the amino-T-acid solution obtained in the step (20) and caustic soda liquid to obtain concentrated amino-T-acid solution and caustic soda liquid; step (40), carrying out alkali fusion treatment on the concentrated amino-T-acid solution and caustic soda liquid obtained in the step (30), and performing attenuation treatment to obtain attenuated alkali fusion matter; step (50), carrying out separation and filtration treatment on the attenuated alkali fusion matter obtained in the step (40) to obtain the H-acid. The preparation method disclosed by the invention adopts the clean process for preparing the H-acid, the production efficiency is high, the materials are saved, and the economic cost is reduced.
Method for preparing energy-efficient H-acid
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Paragraph 0042; 0043; 0044; 0045; 0046, (2016/10/08)
The invention discloses a method for preparing energy-efficient H-acid. The method comprises the steps of conducting sulfonation on liquid naphthalene to obtain a sulfonated substance, conducting nitration on the sulfonated substance to obtain a nitrated substance, conducting denitration on the nitrated substance to obtain a denitrated substance, conducting extraction on the denitrated substance to obtain dilute sulphuric acid and an extraction mixture, conducting reextraction on the extraction mixture to obtain nitro T-acid solution, conducting reduction on the nitro T-acid solution to obtain amino T-acid solution, conducting concentration on the amino T-acid solution and caustic soda liquid to obtain concentrated amino T-acid solution and caustic soda, conducting alkali fusion and dilution on the concentrated amino T-acid solution and caustic soda to obtain a diluted alkali fusion substance, conducting separation and filtration on the diluted alkali fusion substance to obtain H-acid filter cakes, and conducting drying on the H-acid filter cakes to obtain H-acid. By the adoption of the method, continuous production of H-acid can be achieved, and economic cost is low.
The positional reactivity order in the sulfur trioxide sulfonation of benzene and naphtalene derivatives containing an electron-withdrawing substituent
Cerfontain, Hans,Zou, Yousi,Bakker, Bert H.
, p. 403 - 410 (2007/10/02)
The reaction of sulfur trioxide with derivatives of benzene and naphthalene containing an electron-withdrawing substituent, viz.-SO3H, -SO2Ph, -NO2, -CHO, -COPh, -CO2H, and -CO2Me, in dichloromethane as solvent at ca. 22 deg C has been studied by analysis of the resulting mixtures of the sulfo derivatives with 1H-NMR.The initial sulfonation of the benzene derivatives yields the corresponding 3-sulfonic acid (3-S) and subsequently, with the exception of nitrobenzene and methyl benzoate, small amounts of 3,5-S2.Benzenesulfonic acid in addition undergoes sulfonylation giving 3,3'-di- and 3,5,3'-trisulfodiphenyl sulfone.Monosulfonation of naphtalene-1-S yields the 1,5-S2, 1,6-S2 and 1,7-S2 derivatives in a ratio of 71:20:9.On using a large excess of SO3, the eventual products are 1,3,5-S3, 1,3,6-S3 and 1,3,5,7-S4.Monosulfonation of naphthalene yields 5-S, 6-S, 7-S and 8-S in a 55:9:6:30 ratio, that of 1-benzoylnaphthalene 5-S, 6-S and 7-S in a ratio of 83:11:6, and 1-nitronaphtalene only the 5-S.The absence of peri sulfonation with 1-sulfo-, 1-benzoyl- and 1-nitronaphthalene is due to prohibitive steric hidrance. 1-Naphthoic acid and its methyl ester upon SO3 sulfonation and aqueous work-up both yield 5- and 8-sulfonaphthoic acid in a ratio of 65:35 and 77:21, respectively.The initially formed peri-substituted product is the intramolecular anhydride of 8-sulfo-1-naphthoic acid (5).All the 2-substituted naphthalenes yield 5-S and 8-S upon SO3 sulfonation of which the former sulfo isomer is far in excess.The positional reactivity orders for the SO3 sulfonation of the monosubstituted naphthalene derivatives are discussed in terms of the difference in reactivity of the α- and β-positions, and the steric and electronic effects of the deactivating substituent.