A method for preparing bio adipic acid includes steps of (a) preparing a glucaric acid potassium salt by mixing and reacting glucose, nitric acid (HNO.sub.3), sodium nitrite (NaNO.sub.2) and potassium hydroxide (KOH), (b) preparing glucamide from the glucaric acid potassium salt prepared in the step (a), (c) preparing 2,4-hexadiene diamide by performing a deoxydehydration reaction on the glucamide prepared in the step (b), (d) preparing adipamide by introducing the 2,4-hexadiene diamide prepared in the step (c), hydrogen and a hydrogenation catalyst to a reactor and performing a hydrogenation reaction, and (e) preparing adipic acid by introducing the adipamide prepared in the step (d) and an aqueous hydrochloric acid solution to a reactor and then performing a hydrolysis reaction at a specific temperature.

A method for producing adipic acid and cyclohexanone oxime from cyclohexane is provided. Cyclohexane and NO.sub.x undergo oxidation-nitration reaction to produce a mixture of adipic acid, nitrocyclohexane, nitrogen oxides and by-product A, from which adipic acid and nitrocyclohexane are separated. The nitrocyclohexane is catalytically hydrogenated with hydrogen to produce cyclohexanone oxime and a small amount of cyclohexylamine, where cyclohexanone oxime is collected, and the cyclohexylamine is partially oxidized with molecular oxygen to obtain cyclohexanone oxime and by-product B. Without separation, or after removing part or all of water from the reaction mixture, under the action of a catalyst, the reaction mixture undergoes hydrogenation and amination simultaneously or sequentially, or the hydrogenation alone, and separation to give cyclohexanone oxime.

Described herein is an improved conversion of nitrous oxide (N.sub.2O) present as a by-product in a chemical process to NO.sub.x which can be further converted to a useful compound or material, such as nitric acid.

Described herein is an improved conversion of nitrous oxide (N.sub.2O) present as a by-product in a chemical process to NO.sub.x which can be further converted to a useful compound or material, such as nitric acid.

A method for producing dicarboxylic acid. The method includes: subjecting a raw material system including a cyclic olefin and a lower monocarboxylic acid to an addition reaction in the presence of an addition reaction catalyst to generate an intermediate product system including cyclic carboxylic acid ester; and subjecting the intermediate product system including cyclic carboxylic acid ester to a ring-opening and oxidation reaction in the presence of an oxidant and an oxidation catalyst to generate a corresponding dicarboxylic acid product. The addition reaction in the dicarboxylic acid synthesis route achieves a high single-pass conversion rate, and the selectivity of the corresponding cyclic carboxylic acid ester is high. The addition-oxidation synthesis route achieves faster reaction rates for both the addition reaction and oxidation reaction, and high yield of corresponding dicarboxylic acid product. The addition-oxidation based synthesis route is suitable for continuous, stable and large-scale production of corresponding dicarboxylic acid product.

A method for producing dicarboxylic acid. The method includes: subjecting a raw material system including a cyclic olefin and a lower monocarboxylic acid to an addition reaction in the presence of an addition reaction catalyst to generate an intermediate product system including cyclic carboxylic acid ester; and subjecting the intermediate product system including cyclic carboxylic acid ester to a ring-opening and oxidation reaction in the presence of an oxidant and an oxidation catalyst to generate a corresponding dicarboxylic acid product. The addition reaction in the dicarboxylic acid synthesis route achieves a high single-pass conversion rate, and the selectivity of the corresponding cyclic carboxylic acid ester is high. The addition-oxidation synthesis route achieves faster reaction rates for both the addition reaction and oxidation reaction, and high yield of corresponding dicarboxylic acid product. The addition-oxidation based synthesis route is suitable for continuous, stable and large-scale production of corresponding dicarboxylic acid product.

Proposed is a method of preparing glucaric acid from glucose through TEMPO oxidation. The method of preparing glucaric acid includes (a) reacting glucose in a solvent through an oxidation reaction using 4-acetamido-TEMPO serving as a nitroxide radical-mediated organocatalyst, potassium bromide serving as a co-catalyst, and potassium hypochlorite serving as an oxidizing agent to prepare glucaric acid. The method can improve the conversion efficiency of glucose to glucaric acid through optimal conditions of the temperature, pH, and input of the oxidizing agent in an oxidation reaction using a TEMPO acid catalyst.

A process utilizing nitric acid and oxygen as co-oxidants to oxidize aldehydes, alcohols, polyols, preferably carbohydrates, specifically reducing sugars to produce the corresponding carboxylic acids.

The invention describes processes to convert biomass char, such as levulinic acid process char, into useful products.