WO2013077738A1

WO2013077738A1 - A method for the preparation of a fuel, by the addition of one or more components to a base fuel

Info

Publication number: WO2013077738A1
Application number: PCT/NL2012/050839
Authority: WO
Inventors: Michael Dirk Boot; Henricus Antoine Maria VAN DE WATER
Original assignee: Progression-Industry B.V.; Econvex Technologies B.V.
Priority date: 2011-11-25
Filing date: 2012-11-26
Publication date: 2013-05-30
Also published as: NL2007874C2

Abstract

The present invention relates to a method for the preparation of a fuel, by the addition of one or more components to a base fuel, wherein the method comprises the following steps: • i) providing a base fuel, • ii) withdrawing aromatic components from a styrene / propylene ox ide production plant, • iii) adding the components obtained according to step ii) to said base fuel obtained according to step i) for the preparation of said fuel. The invention further relates to a fuel obtainable by the method.

Description

Title: a method for the preparation of a fuel, by the addition of one or more components to a base fuel

The present invention relates to the use of chemical compounds present in a styrene production process in a commercial fuel.

Cyclic oxygenates, like 1-phenylethanol, 2-phenylethanol, acetophenon, benzaldehyde, benzyl alcohol and dimers of these products, are present in large quantities in the chemical process that produces two products, propylene oxide and styrene monomer. Companies like Shell Chemicals, Repsol and Lyondell Basell, are operating these types of processes in various parts of the world. Not all processes are exactly the same, but the earlier mentioned products are in all these processes present. Commercially styrene is also co-produced with propylene oxide in a process known as POSM (Lyondell Chemical Company) or SM/PO (Shell) for styrene monomer / propylene oxide. In this process ethyl benzene is treated with oxygen to form the ethyl benzene hydro peroxide. This hydro peroxide is then used to oxidize propylene to propylene oxide. The resulting 1-phenylethanol is dehydrated to give styrene.

US patent No. 5,675,055 relates to a method in which the organic- containing spent caustic stream from propylene oxide/styrene monomer production, after distillation to separate water and to recover light organics, is treated with an aqueous strong acid, such as H2 S04, and with a higher boiling organic solvent such as the heavy organic residue produced in the propylene oxide/styrene monomer process in an acidification/extraction step. If predistillation is employed, the distilled salt-free water can be recycled as process water and the light organics can be burned as fuel. Thus the organics contained in the waste caustic stream are recovered in the organic phase and can be used as fuel in boiler systems.

US 2011/0121228 relates to a method for the recovery of an aqueous waste stream, from a co-production plant of propylene oxide, styrene and derivatives (SM/PO), by the reduction in the value of the chemical oxygen demand (COD) of aqueous waste streams with high contaminant load and the use of the recovered organic matter. In such a waste stream from the washing process of the product resulting from the epoxidation of propylene with ethylbenzene hydroperoxide from a SM/PO co-production plant methylbenzyl alcohol and monopropylene glycol are recovered and used as fuel in the energy co-generation boilers. US 2010/0078391 relates to a method of reducing sodium content in a heavy residue formed in the POSM process for the co-production of propylene oxide and styrene. The POSM process as disclosed in U.S. Pat. No. 3,351 ,635 involves the oxidation of ethyl benzene to form ethyl benzene hydroperoxide, the catalytic reaction of the hydroperoxide with propylene to form propylene oxide and 1 -phenyl ethanol, and the dehydration of the 1 -phenyl ethanol to produce styrene monomer. In the POSM process, ethyl benzene is first reacted with molecular oxygen at elevated temperature in accordance with known techniques to form ethyl benzene hydroperoxide. U.S. Pat. No. 4,066,706 provides a comprehensive description of this reaction. Suitably, a small amount of alkali is incorporated in the oxidation mixture in order to improve oxidation rate and selectivity, as described in U.S. Pat. No. 4,262, 143.

International application WO 2005/054157 relates to a method for manufacturing styrene, i.e. the coproduction of propylene oxide and styrene starting from ethyl benzene. Such a process involves the steps of (i) reacting ethyl benzene with oxygen or air to form ethyl benzene hydro peroxide, (ii) reacting the ethyl benzene hydro peroxide thus obtained with propene in the presence of an epoxidation catalyst to yield propylene oxide and 1-phenyl-ethanol, and (iii) converting the 1-phenyl-ethanol into styrene by dehydration using a suitable dehydration catalyst.

US Patent No 6504038 relates to a process for the joint preparation of styrene and propylene oxide. Such process is commonly referred to as styrene monomer/propylene oxide (SM/PO) process. In general, a SM/PO process comprises the steps of: (a) reacting ethene and benzene to form ethyl benzene, (b) reacting ethyl benzene with oxygen or air to form ethyl benzene hydro peroxide, (c) reacting at least part of the ethyl benzene hydro peroxide obtained with propene in the presence of an epoxidation catalyst to form propylene oxide and 1 -phenyl ethanol, and (d) dehydrating at least part of the 1 -phenyl ethanol obtained into styrene in the presence of a suitable dehydration catalyst.

The above SM/PO process is well known in the art. In step (a) ethyl benzene is formed by the alkylation of benzene in an ethyl benzene unit. The benzene can, for instance, be derived from a platformer, whilst ethene can be derived from a steam cracking unit. A further suitable process is the process known as the Mobil/Badger process. In this process a synthetic zeolite catalyst, ZSM-5, is used. The preparation of ethyl benzene from ethene and benzene over a zeolitic catalyst is disclosed in U.S.Pat.No. 4,107,224. Step (a) of the process can be carried out independently from process steps (b) to (d), i.e. at a different location. However, it is preferred that the ethyl benzene production matches the styrene production in step (d), so that the ethyl benzene unit is an integrated part of the SM/PO process or is located in the vicinity of a SM/PO plant. A SM/PO plant with an integrated ethyl benzene unit is generally preferred.

In the oxidation step (b) liquid phase oxidation of ethyl benzene into ethyl benzene hydro peroxide occurs at a temperature of 100-160[deg.] C and at a pressure of 1-4 bar. The oxidation is typically carried out with air as the oxidizing gas, but oxygen may also be applied. The main by-product formed at this stage is acetophenone, which may be hydrogenated in the SM/PO process into 1-phenylethanol, used in step (d) to produce styrene. In the epoxidation step (c) ethyl benzene hydro peroxide is reacted with propene to yield propylene oxide and 1 -phenyl ethanol or substituted 1 -phenyl ethanol. In such epoxidation step a homogeneous catalyst or a heterogeneous catalyst can be applied. The effluent from the epoxidation step is normally first subjected to a separation treatment to remove the propylene oxide formed, after which the residual stream, containing 1- phenyl ethanol, is suitably subjected to one or more further separation treatments, inter alia to remove ethyl benzene for reuse in an earlier stage of the process. The eventually obtained 1 -phenyl ethanol containing stream is then subjected to the dehydration treatment in step (d). The dehydration of 1 -phenyl ethanol into styrene can be carried out both in the gas phase and in the liquid phase. Dehydration conditions include reaction temperatures of 100-210[deg.] C. for liquid phase dehydration and 210-320[deg.] C, typically 280-310[deg.] C, for gas phase dehydration. Pressures usually range from 0.1 to 10 bar. In principle any known dehydration process can be applied in step (d).

In a commercial SM/PO process the propene used in step (c) can be supplied either from an external source or can be made at the SM/PO site itself, normally in a steam cracking unit (also commonly referred to as ethene plant). A SM/PO process comprising the steps (a) to (d) as described above requires equal amounts of ethene and propene as feedstock. Because of this, SM/PO plants are typically located in the vicinity of an ethene plant, which produces both the required ethene and propene. Accordingly, if a new SM/PO plant is to be designed and built, this plant is normally either located near an existing ethene plant having an overcapacity of ethene and propene or an ethene plant must be included in the design to ensure the necessary ethene and propene.

Products like 1-phenylethanol and acetophenon are so called styrene precursors. These are intermediates that are formed in this PO-SM or SM-PO process. Products like benzaldehyde, benzylalcohol and to some extent 2-phenylethanol and the dimers will not be converted into styrene monomer. Consequently they have a lower value more close to fuel value or even lower. In the PO-SM and SM-PO process, the streams that contain these chemical compounds, are stored in large storage tanks and the non styrene precursors are extracted from the process via various distillation steps. Consequently all the above mentioned chemical products can be taken out of the process or production unit in a simple way.

An object of the present invention is to use of the aromatic, oxygen rich components present in the styrene process for another application.

Another object of the present invention is to manufacture a fuel having a high caloric value.

The present invention thus relates to a method for the preparation of a fuel, by the addition of one or more additives to a base fuel, wherein the method comprises the following steps:

i) providing a base fuel,

ii) withdrawing aromatic components from a styrene production plant,

iii) adding the components obtained according to step ii) to said base fuel obtained according to step i) for the preparation of said fuel.

In a preferred embodiment of the present invention the aromatic components in step ii) comprise oxygenated aromatic components. The amount of components is in the range of 1-20 vol.%, preferably 5-10 vol. %, on basis of the total fuel composition, i.e. base fuel + components. The base fuel according to step i) is selected from the group consisting of diesel fuel, jet fuel, kerosine, gasoline, bunker fuel, synthetic or Fischer- Tropsch fuels, vegetable oils and so-termed biofuels, and mixtures thereof, especially selected from the group of jet fuel, gasoline and diesel.

In an embodiment the styrene production plant according to step i) is a process selected from the group PO-SM process and SM-PO process.

The aromatic components in step ii) comprise preferably styrene precursor components, and the aromatic components in step ii) comprise preferably waste products that have not been converted into styrene monomer. Examples of styrene precursor components in step ii) comprise one or more of 1-phenylethanol, 2-phenylethanol and acetophenon. Examples of the waste products comprise one or more of benzaldehyd, benzyl alcohol, BPE and dimers like DPEE (diphenylene ethyl ether).

The present invention relates furthermore to a fuel, comprising a base fuel and one or more components, wherein one or more components are aromatic components and originate from a styrene production plant. The base fuel is preferably selected from the group consisting of diesel fuel, jet fuel, kerosine, gasoline, bunker fuel, synthetic or Fischer-Tropsch fuels, vegetable oils and so-termed biofuels, and mixtures thereof.

In an embodiment the styrene production plant is a process selected from the group PO-SM process and SM-PO process.

The present fuel is characterized in that said one or more components are chosen from the group consisting of 1-phenylethanol, 2-phenylethanol, acetophenon, benzaldehyd, benzyl alcohol, BPE and dimers like DPEE (diphenylene ethyl ether), or mixtures thereof.

The present inventors found that jet fuel without aromatic hydrocarbons the seals in the fuel circuit will shrink during flight and cause: Synthetic Fischer-Tropsch kerosene is blended because, unlike conventional jet fuel, it contains no aromatic hydrocarbons. While partially responsible for the smoke and soot produced by gas turbines, aromatics also cause elastomeric engine seals to swell.

In addition, for gasoline, the aromatic base generally increases the octane number of the gasoline base fuel. And for diesel, the cyclic oxygenates reduce soot emissions in diesel engines when blended to diesel fuel.

Products like 1-phenylethanol, benzylalcohol and 2-phenylethanol are polar in nature. Accordingly, dissolving such compounds in diesel fuel might require additional surfactant additives and/or elevated fuel temperatures to keep the phases together. In a preferred embodiment the whole stream (i.e. polar + non-polar fractions) is added to diesel first. Subsequently, the polar phase (which does not dissolve and has diesel floating on top) can be extracted and added to either kerosene (jet fuel), gasoline or both. According to another embodiment the whole stream is added directly to gasoline, kerosene (jet fuel) or both.

The liquid fuel composition according to the present invention may contain one or more of the usual additives, such as agents affecting flow at low temperatures, agents suppressing the precipitation of waxy components, stabilisers, antioxidants, agents for improving the cetane number, agents for promoting combustion, detergents, defoaming agents, lubricants, antifoaming agents, antistatic agents, agents for promoting conductivity, corrosion-suppressing agents, fragrances, pigments, friction-reducing agents and the like. The additives commonly used to reduce the emission of nitrogen oxides may also be used in the present liquid fuel.

The present invention relates to the application of specific process streams as additive in a fuel, either in neat form or blended to other fuels, in combustion engines (e.g. compression-ignition, spark-ignition, jet turbines) or burners (e.g. domestic for heating), as swell enhancing compound in jet fuel,. as octane booster in gasoline fuel, as soot reducing compound in diesel fuel.

The present invention will now be illustrated by way of an example. This example is for illustrative purposes only and does not limit the scope of the present invention.

BRIEF DESCRIPTION OF FIGURE.

The sole Figure shows the general concept underlying the present invention. The PO-SM process and SM-PO process is depicted with reference B. Process B has basically two output streams C and D. Stream C is the styrene product, whereas D are the waste products or the products not converted into styrene. Examples of D are benzaldehyd, benzyl alcohol, BPE and dimers like DPEE (diphenylene ethyl ether). Please note that this list is not limitative. The styrene precursors are indicated with reference A. Examples of A are 1-phenylethanol and acetophenone.

The invention must be seen in the extraction of (parts of ) A and D into F, wherein F refers to a base fuel. This means that according the Figure a fuel is prepared by the addition of valuable components from a styrene production plant B, i.e. streams indicated at D and A, to a base fuel.

Claims

1. A method for the preparation of a fuel, by the addition of one or more components to a base fuel, characterized in that the method comprises the following steps: i) providing a base fuel,

ii) withdrawing aromatic components from a styrene production plant,

2. A method according to claim 1 , characterized in that the aromatic components in step ii) comprise oxygenated aromatic components.

3. A method according to any one or more of the preceding claims, characterized in that the base fuel according to step i) is selected from the group consisting of diesel fuel, jet fuel, kerosine, gasoline, bunker fuel, synthetic or Fischer-Tropsch fuels, vegetable oils and so-termed biofuels, and mixtures thereof.

4. A method according to claim 3, characterized in that the base fuel is selected from the group of jet fuel, gasoline and diesel.

5. A method according to any one or more of the preceding claims, characterized in that the styrene production plant according to step i) is a process selected from the group PO-SM process and SM-PO process.

6. A method according to any one or more of the preceding claims, characterized in that the aromatic components in step ii) comprise styrene precursor components.

7. A method according to any one or more of the preceding claims, characterized in that the aromatic components in step ii) comprise waste products that have not been converted into styrene monomer.

8. A method according to claim 6, characterized in that the styrene precursor components in step ii) comprise one or more of 1-phenylethanol, 2-phenylethanol and acetophenon.

9. A method according to claim 7, characterized in that waste products comprise one or more of benzaldehyd, benzyl alcohol, BPE and dimers like DPEE (diphenylene ethyl ether).

10. A fuel, comprising a base fuel and one or more components, characterized that said one or more components are aromatic components and originate from a styrene production plant.

1 1. A fuel according to claim 10, characterized in that that the base fuel is selected from the group consisting of diesel fuel, jet fuel, kerosine, gasoline, bunker fuel, synthetic or Fischer-Tropsch fuels, vegetable oils and so-termed biofuels, and mixtures thereof.

12. A fuel according to one or more of the claims 10-1 1 , characterized in that the styrene production plant is a process selected from the group PO-SM process and SM- PO process.

13. A fuel according to one or more of the claims 10-12, characterized in that said one or more components are chosen from the group consisting of 1-phenylethanol, 2- phenylethanol, acetophenon, benzaldehyd, benzyl alcohol, BPE and dimers like DPEE (diphenylene ethyl ether), or mixtures thereof.

14. A fuel according to one or more of the claims 10-13, characterized in that said one or more components are present in the range of 1-20 vol.%, preferably 5-10 vol.%, on basis of the total fuel composition, i.e. base fuel + components.