In a method for oxidizing 1,1-bis-(3,4-dimethylphenyl)-alkane with nitric acid in a pressure vessel to produce 3,3′,4,4′-benzophenone tetracarboxylic acid with concurrent formation of nitric oxide, passing nitric oxide from the pressure vessel into an absorption vessel and reacting nitric oxide in the absorption vessel with molecular oxygen and water to produce an aqueous nitric acid solution prevents discharge of nitric oxide, avoids the risk of oxygen inhibiting the nitric acid oxidation and reduces nitric acid consumption when the nitric acid from the absorption vessel is used for oxidizing the 1,1-bis-(3,4-dimethylphenyl)-alkane.

In a method for oxidizing 1,1-bis-(3,4-dimethylphenyl)-alkane with nitric acid in a pressure vessel to produce 3,3′,4,4′-benzophenone tetracarboxylic acid with concurrent formation of nitric oxide, passing nitric oxide from the pressure vessel into an absorption vessel and reacting nitric oxide in the absorption vessel with molecular oxygen and water to produce an aqueous nitric acid solution prevents discharge of nitric oxide, avoids the risk of oxygen inhibiting the nitric acid oxidation and reduces nitric acid consumption when the nitric acid from the absorption vessel is used for oxidizing the 1,1-bis-(3,4-dimethylphenyl)-alkane.

The present invention provides an industrially-advantageous process for preparing a benzoyl formic acid compound, and an efficient process for preparing a pyridazine compound using the same process. Specifically, the present invention provides a process for preparing a compound represented by formula (2), which comprises a step (B): a step of reacting a compound represented by formula (1) with a nitrosyl sulfuric acid in water to produce the compound represented by formula (2).

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The present invention provides an industrially-advantageous process for preparing a benzoyl formic acid compound, and an efficient process for preparing a pyridazine compound using the same process. Specifically, the present invention provides a process for preparing a compound represented by formula (2), which comprises a step (B): a step of reacting a compound represented by formula (1) with a nitrosyl sulfuric acid in water to produce the compound represented by formula (2).

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This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.

This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.

A method for synthesizing 4-(Hydroxymethyl)benzoic acid using P-xylene (PX) as a raw material, including: dissolving PX in an organic solvent to undergo an oxidation reaction with an oxidizing agent under an action of an M-MOF catalyst; and after the oxidation reaction, performing a post-treatment to obtain the 4-(Hydroxymethyl)benzoic acid; wherein, the metal element M in the M-MOF catalyst is Fe, Cu, Cr, Mn, Cu/Fe, Cu/Cr, Cu/Mn, Fe/Mn, Cr/Fe or Cr/Mn. The by-product produced in the reaction process is little, the yield is high, and the separation is convenient. The acid-base neutralization is not required in the reaction process, reducing pollution. A one-step reaction is employed which has mild reaction conditions, short reaction time, low pollution and is convenient for industrialized mass production; and the obtained 4-(Hydroxymethyl)benzoic acid can be used for preparing medicines and liquid crystal materials having wide applications.

A method for synthesizing 4-(Hydroxymethyl)benzoic acid using P-xylene (PX) as a raw material, including: dissolving PX in an organic solvent to undergo an oxidation reaction with an oxidizing agent under an action of an M-MOF catalyst; and after the oxidation reaction, performing a post-treatment to obtain the 4-(Hydroxymethyl)benzoic acid; wherein, the metal element M in the M-MOF catalyst is Fe, Cu, Cr, Mn, Cu/Fe, Cu/Cr, Cu/Mn, Fe/Mn, Cr/Fe or Cr/Mn. The by-product produced in the reaction process is little, the yield is high, and the separation is convenient. The acid-base neutralization is not required in the reaction process, reducing pollution. A one-step reaction is employed which has mild reaction conditions, short reaction time, low pollution and is convenient for industrialized mass production; and the obtained 4-(Hydroxymethyl)benzoic acid can be used for preparing medicines and liquid crystal materials having wide applications.

This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.

This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.