The present invention relates to an acetal compound of the following general formula (1) and an acetal compound of the following general formula (2). The present invention relates to processes for preparing the acetal compound (2), comprising subjecting the acetal compound (1) to a hydrogenation reaction to form the acetal compound (2). The present invention provides a process for preparing 2,3,4,4-tetramethylcyclopentanecarbaldehyde of the following formula (3), comprising subjecting the acetal compound (2) to a hydrolysis reaction to form 2,3,4,4-tetramethylcyclopentanecarbaldehyde (3). ##STR00001##

The present invention relates to an acetal compound of the following general formula (1) and an acetal compound of the following general formula (2). The present invention relates to processes for preparing the acetal compound (2), comprising subjecting the acetal compound (1) to a hydrogenation reaction to form the acetal compound (2). The present invention provides a process for preparing 2,3,4,4-tetramethylcyclopentanecarbaldehyde of the following formula (3), comprising subjecting the acetal compound (2) to a hydrolysis reaction to form 2,3,4,4-tetramethylcyclopentanecarbaldehyde (3). ##STR00001##

Provided are a method for producing 3-methylglutaraldehyde in a good yield under a mild condition and a novel acetal compound which is useful for carrying out the foregoing method. The method is a production method of 3-methylglutaraldehyde including a step of hydrolyzing a compound represented by the following general formula (1):

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent an alkyl group having 1 to 6 carbon atoms, or are mutually coupled to represent an alkylene group having 2 to 6 carbon atoms.

Provided are a method for producing 3-methylglutaraldehyde in a good yield under a mild condition and a novel acetal compound which is useful for carrying out the foregoing method. The method is a production method of 3-methylglutaraldehyde including a step of hydrolyzing a compound represented by the following general formula (1):

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent an alkyl group having 1 to 6 carbon atoms, or are mutually coupled to represent an alkylene group having 2 to 6 carbon atoms.

Provided are a method for producing 3-methylglutaraldehyde in a good yield under a mild condition and a novel acetal compound which is useful for carrying out the foregoing method. The method is a production method of 3-methylglutaraldehyde including a step of hydrolyzing a compound represented by the following general formula (1):

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent an alkyl group having 1 to 6 carbon atoms, or are mutually coupled to represent an alkylene group having 2 to 6 carbon atoms.

The present invention is related to a catalytic process, which includes catalytic compositions for depolymerisation and deoxygenation of lignin contained in the biomass for obtaining aromatic hydrocarbons. The catalytic composition consists of at least one non-noble element from group VIIIB of the periodic table supported on a mesoporous matrix composed of an inorganic oxide, which can be alumina surface-modified with a second inorganic oxide with the object of inhibiting the interaction between the active component and the support. The process of lignin depolymerisation consists of dissolving lignin in a mixture of protic liquids, reacting it I a reaction system by batch or in continuous flow at inert and/or reducing atmosphere, at a temperature of between 60 to 320° C. and a pressure of from 5 to 90 kg/cm.sup.2. When the reaction is developed into a batch system, oxygenated aromatic hydrocarbons are mainly produced, both by thermal as well as catalytic depolymerisation, whereas in a continuous flow reaction system, deoxygenated aromatic hydrocarbons are produced.

The present invention is related to a catalytic process, which includes catalytic compositions for depolymerisation and deoxygenation of lignin contained in the biomass for obtaining aromatic hydrocarbons. The catalytic composition consists of at least one non-noble element from group VIIIB of the periodic table supported on a mesoporous matrix composed of an inorganic oxide, which can be alumina surface-modified with a second inorganic oxide with the object of inhibiting the interaction between the active component and the support. The process of lignin depolymerisation consists of dissolving lignin in a mixture of protic liquids, reacting it I a reaction system by batch or in continuous flow at inert and/or reducing atmosphere, at a temperature of between 60 to 320° C. and a pressure of from 5 to 90 kg/cm.sup.2. When the reaction is developed into a batch system, oxygenated aromatic hydrocarbons are mainly produced, both by thermal as well as catalytic depolymerisation, whereas in a continuous flow reaction system, deoxygenated aromatic hydrocarbons are produced.

The present invention is related to a catalytic process, which includes catalytic compositions for depolymerisation and deoxygenation of lignin contained in the biomass for obtaining aromatic hydrocarbons. The catalytic composition consists of at least one non-noble element from group VIIIB of the periodic table supported on a mesoporous matrix composed of an inorganic oxide, which can be alumina surface-modified with a second inorganic oxide with the object of inhibiting the interaction between the active component and the support. The process of lignin depolymerisation consists of dissolving lignin in a mixture of protic liquids, reacting it I a reaction system by batch or in continuous flow at inert and/or reducing atmosphere, at a temperature of between 60 to 320° C. and a pressure of from 5 to 90 kg/cm.sup.2. When the reaction is developed into a batch system, oxygenated aromatic hydrocarbons are mainly produced, both by thermal as well as catalytic depolymerisation, whereas in a continuous flow reaction system, deoxygenated aromatic hydrocarbons are produced.

A method of converting lignin to phenolic compounds and dicarboxylates in high yield is described. The method involves the use of peroxy acids to react with lignin at a moderated treatment conditions. The peroxy acids can be used along or in combination of other catalysts that have the capability to lower the molecular weight of lignin. A phenolic compounds yield is achieved (>60%) and these phenolic compounds represents high value precursors for various applications include but not limited to antioxidants, health improvement agents, anticorrosive agents, liquid fuel components and performance enhancing agents, resin and adhesives. Dicarboxylic acids can be used for polymer applications or hydrodeoxygenation to hydrocarbon fuel.

A method of converting lignin to phenolic compounds and dicarboxylates in high yield is described. The method involves the use of peroxy acids to react with lignin at a moderated treatment conditions. The peroxy acids can be used along or in combination of other catalysts that have the capability to lower the molecular weight of lignin. A phenolic compounds yield is achieved (>60%) and these phenolic compounds represents high value precursors for various applications include but not limited to antioxidants, health improvement agents, anticorrosive agents, liquid fuel components and performance enhancing agents, resin and adhesives. Dicarboxylic acids can be used for polymer applications or hydrodeoxygenation to hydrocarbon fuel.