Provided are a precursor compound of a tetracyclic hydrocarbon and a preparation method thereof, and a tetracyclic hydrocarbon and a preparation method and use thereof. The precursor compound of the tetracyclic hydrocarbon with a structure shown in formula I has a polycyclic structure. The precursor compound is subjected to hydrodeoxygenation so as to be prepared into the tetracyclic hydrocarbon with a structure shown in formula II that has a high density (0.986 g/cm.sup.3), a high calorific value (41.14 MJ/L), and a low freezing point (less than 60 C.). ##STR00001##

Methods are provided for improving the yield of aromatics during conversion of oxygenate feeds. An oxygenate feed can contain a mixture of oxygenate compounds, including one or more compounds with a hydrogen index of less than 2, so that an effective hydrogen index of the mixture of oxygenates is between about 1.4 and 1.9. Methods are also provided for converting a mixture of oxygenates with an effective hydrogen index greater than about 1 with a pyrolysis oil co-feed. The difficulties in co-processing a pyrolysis oil can be reduced or minimized by staging the introduction of pyrolysis oil into a reaction system. This can allow varying mixtures of pyrolysis oil and methanol, or another oxygenate feed, to be introduced into a reaction system at various feed entry points.

Methods are provided for improving the yield of aromatics during conversion of oxygenate feeds. An oxygenate feed can contain a mixture of oxygenate compounds, including one or more compounds with a hydrogen index of less than 2, so that an effective hydrogen index of the mixture of oxygenates is between about 1.4 and 1.9. Methods are also provided for converting a mixture of oxygenates with an effective hydrogen index greater than about 1 with a pyrolysis oil co-feed. The difficulties in co-processing a pyrolysis oil can be reduced or minimized by staging the introduction of pyrolysis oil into a reaction system. This can allow varying mixtures of pyrolysis oil and methanol, or another oxygenate feed, to be introduced into a reaction system at various feed entry points.

Methods are provided for improving the yield of aromatics during conversion of oxygenate feeds. An oxygenate feed can contain a mixture of oxygenate compounds, including one or more compounds with a hydrogen index of less than 2, so that an effective hydrogen index of the mixture of oxygenates is between about 1.4 and 1.9. Methods are also provided for converting a mixture of oxygenates with an effective hydrogen index greater than about 1 with a pyrolysis oil co-feed. The difficulties in co-processing a pyrolysis oil can be reduced or minimized by staging the introduction of pyrolysis oil into a reaction system. This can allow varying mixtures of pyrolysis oil and methanol, or another oxygenate feed, to be introduced into a reaction system at various feed entry points.

Methods are provided for improving the yield of aromatics during conversion of oxygenate feeds. An oxygenate feed can contain a mixture of oxygenate compounds, including one or more compounds with a hydrogen index of less than 2, so that an effective hydrogen index of the mixture of oxygenates is between about 1.4 and 1.9. Methods are also provided for converting a mixture of oxygenates with an effective hydrogen index greater than about 1 with a pyrolysis oil co-feed. The difficulties in co-processing a pyrolysis oil can be reduced or minimized by staging the introduction of pyrolysis oil into a reaction system. This can allow varying mixtures of pyrolysis oil and methanol, or another oxygenate feed, to be introduced into a reaction system at various feed entry points.

A method for making high density fuels including, heating a renewable plant oil, triglyceride, or fatty acid with at least one first acid catalyst to generate a first mixture of alkyladamantanes, increasing reaction time or adding at least one second catalysts to a first mixture of alkyladamantanes to produce a second alkyladamantane mixture, separating methyl, ethyl, propyl, and/or butyl adamantanes from a second alkyladamantane mixture to produce a third adamantane mixture to produce fuels.

Embodiments of the present invention are directed to the conversion of a source material (e.g., a depolymerized oligosaccharide mixture, a monomeric sugar, a hydrolysate, or a mixture of monomeric sugars) to intermediate molecules containing 7 to 26 contiguous carbon atoms. These intermediates may also be converted to saturated hydrocarbons. Such saturated hydrocarbons are useful as, for example, fuels.

In a specific example according to the present invention, a method is disclosed in which a catalytic reaction is used in order to convert acetic acid, which has been produced by the biological processing or physicochemical processing of biomass, into an aromatic compound constituting a raw material for a high-added-value product such as BTX and, more particularly, p-xylene.

In a specific example according to the present invention, a method is disclosed in which a catalytic reaction is used in order to convert acetic acid, which has been produced by the biological processing or physicochemical processing of biomass, into an aromatic compound constituting a raw material for a high-added-value product such as BTX and, more particularly, p-xylene.

A process comprising (a) providing used tire feedstock; (b) gasifying the used tire feedstock to produce a gaseous stream, where the gaseous stream includes carbon monoxide, hydrogen, and carbon dioxide; (c) biosynthetically converting at least a portion of the carbon monoxide, hydrogen, and carbon dioxide within the gaseous stream to produce a first product stream; (d) converting at least a portion of the first product stream to a second product stream, where the second product stream includes acetaldehyde and hydrogen; (e) routing a portion of the hydrogen within the second product stream to said step of biosynthetically converting at least a portion of the carbon monoxide, hydrogen, and carbon dioxide within the gaseous stream; and (f) converting at least a portion acetaldehyde to butadiene monomer.