WO1996010065A1

WO1996010065A1 - A differential dielectric heating process for crude petroleum

Info

Publication number: WO1996010065A1
Application number: PCT/US1995/000592
Authority: WO
Inventors: John W. Alred; Bass Redd; H. Dean Cubley
Original assignee: Phonon Technologies, Inc.
Priority date: 1994-09-28
Filing date: 1995-01-17
Publication date: 1996-04-04
Also published as: AU1568195A

Abstract

The present invention reveals a method and apparatus for removing contaminants, including water, metals and sulfur containing compounds, from crude petroleum by exposing the petroleum to a differential dielectric heating process. This heating process causes high dielectric contaminants to become concentrated within the crude petroleum. The concentrated contaminants are then removed from the petroleum, thereby yielding a higher quality petroleum. The removal of the contaminants from the crude petroleum by this process can be further enhanced by adding a selective compound to the petroleum prior to exposing the petroleum to the differential dielectric heating process or by washing the petroleum following the heating process or by a combination of these methods.

Description

A DIFFERENTIAL DIELECTRIC HEATING PROCESS FOR CRUDE PETROLEUM

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a process and apparatus for removing contaminants from crude petroleum. More specifically, crude petroleum is subjected to a differential dielectric heating process, thereby causing high dielectric contaminants such as water, metals and sulfur-containing compounds to be concentrated in and subsequently separated from the petroleum.

2. Description of the Related Art

Crude petroleum is a complex, physical mixture of mainly organic chemicals - mostly hydrocarbons and hydrocarbon derivatives ranging from methane to heavy bitumen. Pollutants in crude petroleum (from a processing point of view) include water, metal compounds, and sulfur. In fact, as many as 80% of the molecules in crude can contain sulfur. Also, some molecules in crude contain nitrogen, oxygen, vanadium, nickel, and/or arsenic. These molecules, especially the metals, can be detrimental in the refining process. For example, the metals nickel and vanadium can substantially reduce the lifetime of a catalytic cracking bed. Hence, the higher the grade of crude petroleum, the easier it is to process. As a result, crude petroleum with less impurities (higher grades) bring a better price on the market.

Crude petroleum is graded in accordance with its ease of processing or the amount of impurities contained within the crude. The most common method of measuring the grade of petroleum uses the American Petroleum Institute's Index (API index). By this method, water has an API index of 10.0 while most crude oils have an API index between 10 and 80. Light hydrocarbons (n-pentane and lighter) have values of API index ranging upward from 92.8. Some examples of various crudes and their properties are listed in Table 1.

TABLE 1: Examples of Crude Petroleum

Crude Name API Sulfur(Wt%) Price/Barrel (Aug. 93)

Maya 21.8 3.29 $11.72

Urals-Medit 32.5 1.38 $14.80

Arab Light 33.4 1.79 $14.05

Bonny Medium 25.2 0.23 $16.60

Gippsland 45.4 0.10 $17.25

An examination of the price per barrel emphasizes the importance of sulfur removal.

Metals are contained in the crude petroleum in three forms. The first category is free metals and inorganic metal compounds. The second category is composed of porphyrins and similar derived organometallic compounds. The last category is made up of organometallic compounds left over from the biological process of the organisms whose decay produced the hydrocarbons.

Microwaves have been exploited principally for communications, radar, commercial industrial uses, and commercial consumer items, such as the microwave oven. The term microwave in this application refers to the subset of the radio frequency section of the electromagnetic spectrum with frequencies between 300 MHz and 100 GHz. Many material scientists have recognized the potential of microwave energy for drying, or dehumidifying, due to the ability of many materials, especially water-loaded ones, to absorb microwaves as heat.

The efficiency with which a material absorbs electromagnetic radiation is related to the dielectric constant of the material. The higher the dielectric constant - the more energy that can be absorbed. This fact is the basis for the tremendous popularity of microwave ovens in the home. If a material is a mixture of two or more components with different dielectric strengths, the microwaves will interact with each component differently (sometimes even independent of the other components) . This fact is the basis for differential dielectric heating - the ability of the microwave to heat the components of a mixture separately from the mixture.

In terms of microwaves, oil is almost a transparent medium. The hydrocarbons that constitute crude petroleum have dielectric constants between 1 and 3 (see Table 2) . However, water has a dielectric constant of 78. TABLE 2: Dielectric Constants of Some Materials

Material Dielectric Constant n-Hexane 1.89

Petroleum 1.5-2.5

Ferrous Sulfide 14.2

Water 78.0

The present inventors have exploited the fact that water, metals and sulfur containing compounds have high dielectric constants compared to those for the hydrocarbons in crude petroleum in order to develop a process and apparatus for removing contaminants from crude petroleum.

SUMMARY OF THE INVENTION

In the present application, a process and an apparatus for removing contaminants, including water, metals and sulfur containing compounds, from crude petroleum is disclosed.

The process involves exposing the crude petroleum to a differential dielectric heating process. The contaminants within the crude petroleum are then allowed to concentrate and the concentrated contaminants are subsequently removed from the petroleum. The differential dielectric heating process uses radio frequencies between 300 MHz and 100 GHz and in particular microwave frequencies.

The process may be further enhanced by the addition of material such as a chlorine-containing substance or a catalyst prior to exposing the crude petroleum to the differential dielectric heating process. The process may also be enhanced by washing the petroleum with a material such as a chlorine- containing substance or sodium hydroxide after exposing the crude petroleum to the differential dielectric heating process. Even greater enhancement of the process can be achieved by combining the addition of a material prior to the exposure and the washing of the petroleum with a material after the exposure.

The apparatus for the removal of contaminants from crude petroleum is comprised of a dielectric heating oven and a flow applicator. The flow applicator comprises a tube or container with a fill tube at one end and top and bottom flow tubes at the other end. The flow applicator is mounted within the resonance cavity of the oven. The dielectric heating oven is capable of emitting radio frequencies between 300 MHz and 100 GHz and in particular microwave frequencies.

BRIEF DESCRIPTION OF THE DRAWING

Figure 1 graphically illustrates the interaction of suspended metals with microwaves in a crude petroleum sample.

Figure 2 shows changes in the API index obtained by exposing Maya Crude petroleum to the differential dielectric heating process for varying periods of time.

Figure 3 shows changes in the API index obtained by exposing Alaskan North Slope (ANS) Crude petroleum to the differential dielectric heating process for varying periods of time.

Figure 4 is a graphic representation of the apparatus of the present invention for exposing crude petroleum to a differential dielectric heating process.

Figure 5 shows the effect of varying times for the microwave exposure on the nickel concentration of Maya Crude petroleum.

Figure 6 shows the effect of varying times for the microwave exposure on the vanadium concentration of Maya Crude petroleum.

Figure 7 graphically illustrates the reduction of both nickel and vanadium in Maya Crude petroleum as a function of microwave exposure time. Nickel is represented by -D- and vanadium is represented by -x-.

Figure 8 depicts a comparison of the nickel concentration in untreated Maya Crude, microwave treated, microwave treated with added sodium hypochlorite and microwave treated followed by a sodium hypochlorite wash.

Figure 9 depicts a comparison of the vanadium concentration in untreated Maya Crude, microwave treated, microwave treated with added sodium hypochlorite and microwave treated followed by a sodium hypochlorite wash.

Figure 10 depicts a comparison of the sulfur concentration in untreated Maya Crude, microwave treated, microwave treated with added catalytic iron and microwave treated followed by a sodium hydroxide wash. Figure 11 graphically illustrates the reduction for nickel, vanadium and sulfur for microwave treated Maya Crude, microwave treated with added material prior to exposure and microwave treated followed by a wash as compared to untreated Maya Crude. Nickel is represented by -D-, vanadium by -Δ- and sulfur by -x-.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the petroleum industry, most crude oil produced is mixed with gas and water. While oil and water chemically do not mix, under the right conditions, these two materials can form emulsions that do not physically separate under the influence of gravity alone. Microwaves provide a highly effective means of promoting the separation of water from the hydrocarbons of crude oil. The nature of this process has to do with the high dielectric constant of water versus the low dielectric constant of oil. Hydrocarbons are essentially transparent to microwaves. Water, on the other hand, absorbs the microwaves readily and heats up as a result of the interaction. The effect separates the emulsion.

Metals have dielectric constants that are effectively infinite. This fact means that metals are excellent conductors of electricity. Hence, when an electromagnetic wave strikes a metal surface, it can cause a local flow of electrons. This local flow of electrons is called an eddy current. The eddy current produces resistive heating (also known as ohmic heating) in the same manner that any electric current will produce power in an electric resistor. Similarly, microwaves induce currents within a metal particle which produce this ohmic heating. The particle is surrounded by oil to which it gives heat by conduction. The small region surrounding the metal particle sees a rise in temperature which leads to a reduction of viscosity. Gravity then pulls the metal particle down. Another burst of microwaves at the metal particle initiates the process once again. Hence, from the vantage point of the external observer, these particles seem to wiggle down. In summary, the hot particle in the petroleum cause a thermal lessening of the local viscosity - hence, the metal particle sinks.

This differential dielectric heating effect on metals in crude petroleum is illustrated in Figure l. Crude petroleum 10 containing metal particles 20 is exposed to a microwave pulse 30. The microwaves 30 induce currents within the metal particles 20 which produce ohmic heating. The small region 40 surrounding the metal particles 20 sees a rise in temperature which leads to a reduction of viscosity. Gravity 50 then pulls the metal particles 20 down.

Metal-bearing compounds may also have dielectric constants substantially higher than those of the surrounding crude petroleum. These compounds are affected in a similar manner as the metals. This effect has been noted below where petroleum samples exposed to microwaves have deposited sediment on the bottom of the container.

Sulfur compounds normally exists in petroleum in three forms: pyritic (FeS₂) , organic and sulfates. However, the sulfates usually make up less than 0.05% of the sulfur compounds in petroleum. On the one hand, pyritic sulfur makes up between 20-80% of the sulfur content in coal. Microwaves will cause heating effects in pyritic sulfur (and perhaps some of the more complicated sulfur compounds) . The pyritic sulfur could then descend through the crude in the same manner as a metal compound. Unfortunately, pyritic sulfur in crude petroleum is as rare as elemental sulfur. The remaining organic sulfur is between 80-100% composed of ring-structure hydrocarbons. These compounds will be little affected by the microwaves.

However, most sulfur-bearing hydrocarbons will interact with a heated catalyst - such as iron, platinum, or palladium. Such a catalyst can be added before the microwave heating process. During irradiation with the microwaves, the metal catalyst will perform its thermal random walk to the bottom of the petroleum. In the process it can pick up several molecules of sulfur-bearing compounds. The catalyst can be recovered and recycled for further use.

The following non-limiting examples are used to further illustrate the present invention.

For Examples 1-4, the following procedure was used:

200 ml of crude petroleum was drawn from a well-shaken bulk container and placed into a 250 ml Pyrex beaker. The top 50 ml was drawn off from the beaker via a volumetric pipette as a control sample. The beaker with the remaining 200 ml of crude was placed in a standard, commercially available microwave oven and heated for the predetermined test time. The microwave oven used is rated at 550 W power in the resonance cavity and emitted a single frequency at 2.45 GHz. Tests on samples of 200 ml of distilled water within a 250 ml beaker placed in the middle of the cavity show a temperature rise consistent with an absorption of 360 w. Hence, we conclude that this particular oven has an efficiency to the sample of 65%.

After heating, 100 ml of crude was drawn off the top of the crude petroleum in the beaker via volumetric pipette. This crude sample was placed in a 100 ml graduated cylinder for API testing. Then, the bottom 100 ml of sample was poured from the beaker into another 100 ml graduated cylinder for API testing. After API testing, 50 ml of each graduated cylinder was poured into sterile sample bottles for standard laboratory analysis.

Example l

Table 3 shows the effect of different heating times on the concentration of iron, nickel, sodium and vanadium in the top of a sample of crude petroleum designated Maya Crude. Prior to heating, the Maya Crude sample had concentrations of 1, 28, 12 and 119 ppm for iron, nickel, sodium and vanadium, respectively. After a 60 second microwave exposure, the top of the Maya Crude sample showed concentrations of 0, 24, 11 and 104 ppm for iron, nickel, sodium and vanadium, respectively. The reduction in concentration for each element was even greater when the Maya Crude was subjected to a 120 second microwave exposure.

TABLE 3: RESULTS WITH MAYA CRUDE

DESCRIPTION IRON NICKEL SODIUM VANADIUM

Maya Control Sample 1 28 12 119

Maya tϋ 60 seconds (Top Sample) 24 11 104

Maya (§ 120 seconds (Top Sample) 19 93

Example 2

Similar results were obtained for the Maya Crude in regard to the API index. Figure 2 shows an API index of 20.4 for the untreated Maya Crude, 21.3 after 60 seconds, 21.5 after 120 seconds and 21.6 after 180 seconds of microwave exposure.

Example 3

Table 4 shows similar results with another crude petroleum sample designated Alaskan North Slope or ANS Crude. Prior to heating, the ANS Crude sample had concentrations of 0, 1, 8 and 7 ppm for iron, nickel, sodium and vanadium, respectively. After a 60 second microwave exposure, the top of the ANS Crude sample showed concentrations of 0, 0, 6 and 6 ppm for iron, nickel, sodium and vanadium, respectively. The reduction in concentration for each element was even greater when the ANS Crude was subjected to a 120 second microwave exposure.

TABLE 4: RESULTS WITH ANS CRUDE

DESCRIPTION IRON NICKEL SODIUM VANADIUM

ANS Control Sample 0 1 8 7

ANS @ 60 seconds (Top Sample)

ANS @ 120 seconds (Top Sample)

Example 4

Similar results were obtained for the ANS Crude in regard to the API index. Figure 3 shows an API index of 28.7 for the untreated ANS Crude, 29.2 after 30 seconds, 29.4 after 60 seconds, 29.5 after 120 seconds and 29.6 after 180 seconds of microwave exposure.

For Examples 5-9, a flow applicator which simulates a microwave resonator in a horizontal application was used. The flow applicator was made of plexiglass and measured 10.625" L by 2" W by 6" H internally. The applicator was mounted horizontally in the resonance cavity of a commercial 550 W microwave oven. As seen in Figure 4, holes and slots cut in the side of this oven 60 allowed the connections to the applicator 62 to the fill tube 64 (and the external source of crude petroleum) at one end and the top 66 and bottom 68 flow tubes at the applicator's other end.

This applicator 62 is mounted horizontally in the resonance cavity 70 of the oven 60 and holds approximately one-half U.S. gallon of crude petroleum. The applicator 62 was filled with trapped air bled from the top flow tube 66. In the static mode, no crude petroleum was allowed to flow out of the applicator 62 during microwave heating. In the dynamic mode, the top fill tube 66 was adjusted to a flow rate of 20 ml/min before the microwave heating process was initiated.

A control sample of 20 ml was drawn from the applicator 62 through the top flow tube 66 . The microwave 60 was energized and allowed to heat the applicator 62 for the test's heating profile. 20 ml amounts of crude petroleum were drawn from the top 66 and bottom 68 of the applicator 62 to measure the shift of material due to the microwave effects. These samples were measured for API, bottled in polyethylene sample bottles, labeled, recorded, and taken to a chemical analytic laboratory for standard atomic absorption spectroscopy.

Example 5

The effect of varying times for the microwave exposure on the nickel concentration of Maya Crude is seen in Figure 5. The nickel concentration was reduced to 75% of the that of the control after 2 minutes, to 70% after 3 minutes, to 57% after 6 minutes and to 55% after 10 minutes. Example 6

The effect of varying times for the microwave exposure on the vanadium concentration of Maya Crude is seen in Figure 6. The vanadium concentration was reduced to 79% of that of the control after 2 minutes, to 74% after 3 minutes, to 54% after 6 minutes and to 44% after 10 minutes.

The results in Examples 5 and 6 indicate that both nickel and vanadium are moved from the top to the bottom (or to the sediment) during the heating process. Figure 7 graphically illustrates this reduction for both nickel and vanadium as a function of microwave exposure time.

Example 7

Enhanced metal recovery can be achieved from the crude petroleum by adding a chlorine-containing substance (e.g., sodium hypochlorite, chlorine gas, benzoyl chloride, etc.) to the crude petroleum. This process is referred to as the in situ method.

Enhanced recovery can also be attained by washing the petroleum sample with a chlorine-containing washing solution (e.g. , sodium hypochlorite, chlorine gas, benzoyl chloride, etc.) after heating. This process is referred to as the post- wash method.

The post-wash method involves mixing (via agitation or stirring) the crude petroleum with a washing solution. After the crude petroleum sample has been removed from the microwave oven, the sample is mixed with an equal part of a washing solution in a sterile, third container. The washing solution is made up to the necessary testing concentration in distilled water beforehand. The container is shaken for thirty seconds to mix the crude petroleum and the washing solution. The mixture is allowed to stand for approximately two minutes. The washed petroleum is then separated from the washing solution and the washed petroleum is tested for concentration of contaminants. The optimum values for the concentration of the washing solution, the mixing time and the standing time will depend on the crude petroleum used, the contaminant to be removed and the washing solution used. These optimum values can easily be determined on a case by case basis.

A comparison of the nickel concentration in untreated Maya Crude, microwave treated (MW heat) , microwave treated with added sodium hypochlorite (in situ) and microwave treated followed by a sodium hypochlorite wash (post-wash) are seen in Figure 8. The microwave exposure was for five minutes. One gram of sodium hypochlorite (100 ml of a 6% solution per 100 ml crude petroleum) was used in the post-wash method. The nickel concentration was reduced to 67% of that of the control with microwave treatment, to 55% with the in situ method and to 42% with the post-wash method.

Example 8

Similar results were obtained in regard to vanadium removal. A comparison of the vanadium concentration in untreated, microwave treated, in situ treated and post-wash treated Maya Crude is seen in Figure 9. Again, the microwave exposure was for five minutes and 1 g of sodium hypochlorite (100 ml of a 6% solution per 100 ml of crude petroleum) was used in the post-wash method. The vanadium concentration was reduced to 60% of that of the control with microwave heating, to 30% with the in situ method and to 22% with the post-wash method.

Example 9

Enhanced sulfur recovery can be achieved from the crude petroleum by adding catalytic iron (iron powder) , catalytic platinum and/or catalytic palladium to the crude petroleum before microwave heating. This process is also referred to as the in situ method.

Enhanced sulfur recovery can also be achieved by washing with a washing solution (e.g., sodium hydroxide, various acids, etc.) after the microwave heating. This process is also referred to as the post-wash method and is performed in a manner similar to that described for the post-wash method in Example 7, except for the different washing solution.

The largest enhancement of sulfur recovery can be obtained by combining microwave heating with both the in situ method and the post-wash method. This combined procedure is referred to as All in Figure 10. Microwave exposure was for five minutes. For the in situ method and the All procedure, 1 gram of catalytic iron per 250 ml of crude petroleum was used. In the post-wash method and the All procedure, 250 ml of crude petroleum was washed with 250 ml of 0.1 N sodium hydroxide solution.

A comparison of the sulfur concentration in untreated Maya Crude, microwave treated, in situ treated, post-wash treated and combined (All) treated is shown in Figure 10. The sulfur concentration was reduced to 91% of that of the control with microwave treatment, to 65% with the in situ method, to 52% with the post-wash method and to 25% with the combined methods.

The results from Examples 7, 8 and 9 indicate that nickel, vanadium and sulfur may be removed from crude petroleum by microwave heating. Additional results indicate that the in situ method enhances the removal process and that the post-wash process further enhances the removal process. Figure 11 graphically illustrates this reduction for nickel, vanadium and sulfur for each of the three processes as compared to controls of Maya Crude.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Thus, it is to be understood that variations in both the differential dielectric heating process and apparatus can be made without departing from the novel aspects of this invention as defined in the claims.

Claims

WHAT IS CLAIMED IS:

1. A method for the removal of contaminants from crude petroleum comprising the steps of: a) exposing the crude petroleum to a differential dielectric heating process, b) allowing the contaminants to become concentrated within the petroleum and c) separating the contaminants from the petroleum.

2. The method of claim 1, wherein the differential dielectric heating process comprises the use of radio frequencies between 300 MHz and 100 GHz.

3. The method of claim l, wherein the differential dielectric heating process comprises the use of microwave frequencies.

4. The method of claim 1, further comprising the step of adding a compound to the crude petroleum prior to exposing the crude petroleum to the differential dielectric heating process.

5. The method of claim 4, wherein the added compound is selected from the group consisting of a chlorine-containing substance and a catalyst.

6. The method of claim 1, further comprising the step of washing the petroleum with a washing solution after exposing the crude petroleum to the differential dielectric heating process.

7. The method of claim 6, wherein the washing step is performed with a washing solution selected from the group consisting of a chlorine-containing substance, an acid and sodium hydroxide.

8. The method of claim 4, further comprising the step of washing the petroleum with a washing solution after exposing the crude petroleum to the differential dielectric heating process.

9. The method of claim 8, wherein the added compound is selected from the group consisting of a chlorine-containing substance and a catalyst and the washing step is performed with a washing solution selected from the group consisting of a chlorine-containing substance, an acid and sodium hydroxide.

10. An apparatus for the removal of contaminants from crude petroleum, comprising: a) a dielectric heating oven having a resonance cavity and b) a flow applicator having two ends with a fill tube at one end and top and bottom flow tubes at the other end, wherein said flow applicator is mounted within the resonance cavity of said oven.

11. The apparatus of claim 10, wherein said oven is capable of emitting radio frequencies between 300 MHz and 100 GHz.

12. The apparatus of claim 10, wherein said oven is a microwave oven.

AMENDED CLAIMS

[received by the International Bureau on 20 April 1995 (20.04.95); original claim 4 cancelled; original claims 1, 5, 7, 9 and 11 amended; original claims 5-12 renumbered as claims 4-11; remaining claims unchanged (3 pages)].

1. A method for removal of contaminants, increase of API Index and lowering of viscosity of crude petroleum comprising the steps of: a) adding a compound to the crude petroleum, wherein the added compound is selected from the group consisting of iron, platinum and palladium, b) placing the crude petroleum in a resonance cavity, c) exposing the crude petroleum in the resonance cavity to a differential dielectric heating process, d) allowing the contaminants to become concentrated within the petroleum, e) separating the contaminants from the petroleum and f) recovering petroleum with an increased API Index and a lower viscosity.

3. The method of claim 1, wherein the differential dielectric heating process comprises the use of microwave frequencies.

4. The method of claim 1, further comprising the step of adding a chlorine-containing compound to the crude petroleum prior to exposing the crude petroleum to the differential dielectric heating process.

5. The method of claim 1, further comprising the step of washing the petroleum with a washing solution after exposing the crude petroleum to the differential dielectric heating process.

6. The method of claim 5, wherein the washing step is performed with a washing solution selected from the group consisting of a chlorine-containing substance, and acid and sodium hydroxide.

7. The method of claim 4, further comprising the step of washing the petroleum with a washing solution after exposing the crude petroleum to the differential dielectric heating process.

8. The method of claim 7, wherein the washing step is performed with a washing solution selected from the group consisting of a chlorine-containing substance, an acid and sodium hydroxide.

9. An apparatus for the removal of contaminants from crude petroleum, comprising: a) a dielectric heating oven having a resonance cavity and b) a flow applicator having two ends with a fill tube at one end and top and bottom flow tubes at the other end,

- 23 - wherein said flow applicator is mounted within the resonance cavity of said oven.

10. The apparatus of claim 9, wherein said oven is capable of emitting radio frequencies between 300 MHz and 100 GHz.

11. The apparatus of claim 10, wherein said oven is a microwave oven.

STATEMENT UNDER ARTICLE 19(1)

In the International Search Report dated March 24, 1995, claims 1-9 were not considered novel in view of U.S. Patent 5,055,180 (Klaila) , U.S. Patent 4,234,402 (Kirkbridge) or U.S. 4,279,722 (Kirkbridge) .

Applicant has amended new claim 1 to contain three additional steps. New step a) requires adding a compound to the crude petroleum, wherein the added compound is selected from the group consisting of iron, platinum and palladium. New step b) requires the placing of the crude petroleum in a resonance cavity and step c) is for exposing the crude petroleum in the resonance cavity to a differential dielectric heating process.

None of the cited references teach the addition of iron, platinum or palladium to the crude petroleum. U.S. Patent 4,279,722 (Kirkbridge) discloses the use of platinum in a catalytic hydrogen treating process but subsequent to the fractionation of the crude petroleum.

Furthermore, none of the cited references teach the requirement for exposing the crude petroleum in a resonance cavity to a differential dielectric heating process. Each of the cited patents is believed to disclose the use of a probe and electrodes for the generation of microwaves as compared to the use of a resonance cavity as taught by the present invention.

Also in the International Search Report, claims 1-9 were not considered to involve an inventive step in view of U.S. Patent 3,616,375 (Inoue) . As above, the cited reference does not teach the step of adding iron, platinum or palladium to the crude petroleum and does not teach the step of exposing the crude petroleum in a resonance cavity to a dielectric heating process.

Finally in the International Search Report, claims 10-12 were not considered novel in view of U.S. Patent 3,616,375 (Inoue) . However, the cited reference discloses an apparatus that uses a probe and electrodes for the generation of microwaves. In contrast, the present invention uses a dielectric heating oven having a resonance cavity for the generation of microwaves.

In view of the amendment of the claims and the above statement, it is respectfully submitted that new claims 1-11 are both novel and contain an inventive step over the cited references in the International Search Report.