T 1049/97 22-04-2002

1. Admissibility of the appeals

1.1. The appeal lodged by opponent II (appellant) is admissible.

1.2. Concerning the appeal lodged by opponent I, no statement of grounds was filed. The notice of appeal contains nothing that could be regarded as a statement of grounds pursuant to Article 108 EPC. Opponent I was informed by a letter dated 2 January 1998 that the appeal was likely to be rejected as inadmissible. The possibility of filing a request for re-establishment of rights under Article 122 EPC was also brought to attention, together with the invitation to file observations within two months. No such request was however filed.

By a letter dated 5 July 2001, the Board was informed that they would not express any further opinion on the matter of these appeal proceedings.

As no written statement setting out the grounds of appeal has been filed, the appeal has to be rejected as inadmissible (Article 108 EPC in conjunction with Rule 65(1) EPC) and opponent I is a party to the appeal proceedings as of right (Article 107 EPC, second sentence).

Main request

2. Amendments

Compared with the set of claims as granted, the set of claims forming the present main request contains the following amendments:

(a) Claim 1

The claim has been drawn up as a product-by-process claim by inclusion of the additional features of granted claim 6, the Ni/Al atomic ratio has been amended to read "between 4 and 10" by insertion of the additional features of granted claim 2 and the limitation "spray-dried" has been introduced into the characterizing portion.

These amendments have a basis in the original application: claims 1 to 3 and 8; description: page 6, line 5; page 7, line 27; examples.

(b) Claim 3

The term "pore radius" has been amended to read "pore size". Basis for this amendment can be found in the original application: page 1, lines 29 to 30; page 2, line 3; examples.

(c) Claim 5

The combination of features forming the subject-matter of claim 1 as granted has been included into granted claim 6 together with the following further modifications: The Ni/Al atomic ratio has been amended to read "between 4 and 10"; after collection, the precipitate is "spray-dried".

These amendments have a basis in the original application, respectively: claims 1 to 3 and 8; description: page 6, line 5; page 7, line 27; examples.

(d) The other amendments are of an editorial nature.

2.1. Since all the above amendments have a basis in the original application, the requirements of Article 123(2) EPC are fulfilled. Furthermore, since these amendments restrict the scope of the claims as granted, the requirements of Article 123(3) EPC are also met.

2.2. The claims of the main request and the amended description do not give rise to any objection under Article 84 EPC.

Moreover, in view of the amendments filed during the oral proceedings, wherein the examples and the process steps which do not fall under the claims have been identified, it is possible to establish the examples which fall within the definition of claim 1.

3. Novelty

The novelty of the subject-matter of claim 1 was not contested and the Board sees no reason to take a different position.

4. Inventive step

4.1. The opposed patent concerns nickel/alumina catalysts, their preparation and use.

Such catalysts were known, eg from E1, which the Opposition Division and the respondent considered to be the closest prior art, as well as from H5, which was indicated as another possible starting point by the Board.

4.1.1. E1 describes the results of a study on the formation of the nickel surface, its dispersity and its thermal stability as functions of the nature of the support and the Ni/Al ratio in catalysts prepared by co-precipitation with sodium carbonate. The effects of the reduction temperature on the dispersity of nickel-aluminum catalysts containing 20 to 100% nickel have also been studied. Particular aspects of that study include:

(a) The total surface of the samples in relation to the nickel content (Figures 1 and 2 and relevant comments).

(b) The effect of the temperature of reduction on the mean particle size of metallic nickel and on the degree of reduction (Alpha) of nickel (Figures 3a, 3b and 4a, and table 1).

(c) The effect of the degree of reduction on the magnitude of the metallic nickel surface in catalysts which differ in nickel content and reduction temperature (Figure 4b).

(d) The dependence of metallic nickel surface per gram of nickel introduced on content of nickel (Figure 5, curve 3).

The nickel-aluminum catalysts described in E1 are said to be typical examples of coprecipitated hydrogenation catalysts (page 430, first paragraph, first sentence).

The most relevant physical properties of the catalysts are shown in Table 1, where, inter alia, a nickel-alumina catalyst containing 90% by weight Ni, with a Ni/Al atomic ratio of 7.85, reduced at a temperature of 400° with a nickel surface of 84 m2/g of catalyst, a degree of reduction of 70% and a dispersity of metallic nickel of 44 Å, is described.

4.1.2. H5 relates to nickel upon alumina catalysts, their preparation and their use in various hydrogenation reactions.

It discloses a nickel upon transition alumina catalyst, containing 5 to 40% (w/w) of nickel, characterized in that the catalyst has an active nickel surface area between 80 and 300 m2/g Ni and in which the nickel crystallites have an average diameter of 1 to 5 nanometers (claim 1).

Preferably, the active nickel surface face area ranges between 100 and 250 m2/g Ni and the average nickel crystallite size is of 1.5-3 nanometers (claim 2).

The transition alumina has a total surface area between 45. and 350 m2/g (claim 3) and a pore volume of 0.3 to 0.7. l/kg, the particle size being from 10-5 to 10-2 m (page 1, lines 28 to 29).

The catalysts are manufactured by a process in which a mixture of transition alumina in an aqueous solution of a nickel ammine complex is heated to a temperature of 60-100°C, preferably 75-95°C, as a result of which the precipitation of nickel hydroxide is caused, whereafter the catalyst suspension is separated and dried, if need be calcined and reduced (claim 4).

These catalysts contain metallic nickel (after reduction) distributed over the internal and external surfaces of the carrier particles (page 6, lines 6 to 9). In particular, the nickel is dispersed for at least 95% in the pores of the alumina (i.e. on the internal surface) and the degree of reduction of nickel oxide to nickel is normally at least 50% (reduction for 30. minutes at 500°C with 15 m3 H2 (STP) per kg nickel) (page 3, lines 1 to 5).

These catalysts are very useful for the hydrogenation of inter alia fatty materials, such as fatty acids and their esters (page 6, lines 17 to 20). For slurry hydrogenation powders are preferred (page 1, line 34).

The catalysts may be used in the fixed bed hydrogenation of fatty materials such as acids, nitriles, alcohols and esters, in particular triglycerides. The activity and poison resistance of the catalysts are improved as a result of their high active nickel surface area. In the case of fatty acid hydrogenation a dramatic improvement in colour of the fatty acids was noted (page 7, lines 8 to 17).

In the case of fatty acid ester hydrogenation, a good selectivity, i.e. low linolenic acid content and a low content of fully saturated esters, could be achieved. This is especially important in the hydrogenation of triglycerides such as soybean oil and fish oil (page 7, lines 19 to 23).

The hydrogenation of fish oil is illustrated in example XIV. A catalyst was ground and sieved and the fraction having a particle size below 30 micrometers was used for the hardening of fish oil. The catalyst was highly active and selective and it formed relatively low amounts of saturated triglycerides.

4.2. Although E1 describes a catalyst that has the highest number of structural features in common with the claimed subject-matter, it does not mention the same purpose and effect as the opposed patent, nor does it relate to the same or a similar technical problem. In fact, E1 does not mention any use of the catalysts for hydrogenation of fatty materials such as edible oils. The properties associated with that hydrogenation, such as filterability, activity and selectivity, are not addressed in E1. Also, pore volume and pore size are not specified in E1, although rate and selectivity of fatty material hydrogenation are affected by these properties (see E6 or U7 in this respect).

H5 not only relates to the same technical field of hydrogenation catalysts, to their use for the hydrogenation of fatty materials such as edible oils like soybean oil and fish oil, to good selectivity and activity, to low linolenic content and a low content of fully saturated esters, but also discloses a solution to the technical problem of manufacturing hydrogenation catalysts with a high active nickel surface area and improved activity and poison resistance. Furthermore, the catalysts described in H5 also have a number of structural features in common with the catalysts making the subject-matter of the patent in suit.

Therefore, H5 rather than E1 qualifies as the closest prior art document.

4.3. Although the catalysts described in H5 have adequate properties such as good activity and selectivity in the hydrogenation of unsaturated triglycerides oils, their activity in relation to the volume of catalyst still leaves room for improvement.

Thus, the technical problem underlying the patent in suit can be seen as the preparation of catalysts with adequate catalytic and filtration properties in the hydrogenation of unsaturated triglycerides oils as well as a high Ni/Al ratio, in line with the original formulation of the problem (page 1, lines 15 to 38, of the original application).

4.4. According to the patent in suit, the above defined problem is solved by a catalyst as defined in claim 1, having a Ni/Al atomic ratio of 4 to 10 and being obtainable by the sequential-precipitation and spray-drying steps as defined.

The examples in the patent in suit show that the claimed catalysts have a Ni/Al ratio that is higher than that of the catalysts described in H5, so that less weight or volume of catalyst may be used per weight of feedstock in order to reach a certain effect.

Example XIV of H5, the only example which describes slurry hydrogenation of fish oil under conditions comparable to those given in the patent in suit, gives details about the preparation of the catalyst used as well as its properties such as a time of 93 minutes to reach a iodine value of 82 and a melting point of 31°C for the hardened oil, which values are a yardstick for the selectivity (patent in suit, page 4, lines 16 to 18).

The corresponding values for the melting points of the hydrogenated oils and the time to reach the given iodine value as given in examples 2 and 4 to 6 in the patent in suit are: 33, 32, 33 and 33°C; 120, 130, 97 and 80 minutes, respectively. From these values it can be seen that the claimed catalysts, in spite of having a higher Ni/Al ratio, have a selectivity which is comparable to or even improved over the catalyst of example XIV of H5, in line with the statement in the patent in suit on page 2, lines 27 to 30.

Furthermore, from the properties of the catalysts of comparative examples 1 and 2 in the patent in suit, which are prepared by co-precipitation rather than by sequential precipitation as the claimed catalysts, it can be seen that green cake filterability (32 minutes in the comparative experiments vs. 9, 2.5, 2 and 2. minutes in examples 2 and 4 to 6) as well as the fish oil activity (110 vs. 128, 125, 140 and 150%) are improved despite the fact that the claimed catalyst has a higher or equal Ni/Al ratio (5 vs. 10.0, 10, 6 and 5).

In view of the above, the Board comes to the conclusion that the catalysts according to the patent in suit have adequate catalytic properties and filterability as well as a higher Ni/Al ratio compared to the catalysts prepared by co-precipitation or those of H5, so that the above-defined technical problem has been effectively solved.

4.5. It remains to be decided whether the claimed subject-matter was obvious having regard to the documents on file.

4.5.1. Although H5 discloses catalysts with adequate catalytic properties for hardening edible oils, these catalysts have a nickel content of 40% at most, preferably of 25% at most (page 6, second paragraph, last three sentences). H5 neither hints at increasing the amount of nickel loaded on the alumina, nor does it suggest how this could be achieved without detrimental effects on the catalytic properties and on the filterability.

Consequently, H5 by itself cannot render the claimed subject-matter obvious.

4.5.2. E1 cannot supplement the disclosure of H5, because its general teaching is that the nickel-aluminum catalysts reach their optimum nickel surface at a Ni content of 40% by weight and the usefulness of the catalyst does not increase further with higher Ni contents, (Figure 5, curve 3; penultimate paragraph of page 431 of E1). Thus, E1 does not suggest to increase the Ni content to increase the usefulness of the catalyst.

Although E1 exemplifies a catalyst with a Ni/Al ratio of as high as 7.85, that catalyst was prepared by co-precipitation. It is not apparent that that catalyst would possess all of the physical properties as defined in claim 1, which relates to catalysts prepared by sequential precipitation and spray-drying. In fact, the claimed catalysts show an improved activity in hydrogenation of fish oil over those that have been prepared by co-precipitation (see point 4.4 supra).

E1 does not mention hardening of edible oils, let alone any suitability of the catalysts therefor, nor does it disclose any preparation method for suitable catalysts therefor or hint at any other preparation procedure than co-precipitation.

Since the information of E1 does not refer to the objectives of the patent in suit and the indications in E1 go against the objective as stated in H5, the skilled person would not have combined the teachings of documents E1 and H5.

Even if the skilled person had combined these two documents, in view of the specific preparation of the claimed catalysts, the relevant properties thereof would still be distinct over the co-precipitated catalysts, so that the skilled person would not have arrived at the claimed subject-matter.

4.5.3. Even if E1 were to be used as the starting point, the conclusion would not be any different:

(a) Though the catalysts of E1 have a number of features in common with the claimed catalysts, this document does not mention a technical problem related to that of the patent in suit.

Consequently, a technical problem arising from E1 would have to be defined in so general terms that its solution could practically never be obvious, because no chain of considerations leading in an obvious way to the claimed subject-matter could be established. Thus, the claimed subject-matter is non-obvious in the light of such art.

(b) Even if it could be taken for granted that Ni/Al catalysts are generally suitable for hydrogenation, that the catalysts of E1 would inevitably be suitable for hydrogenation of fatty materials, and that the technical problem over E1 was the mere provision of alternative catalysts, the skilled person would find no hint at any alternative solution as defined in claim 1.

No cited document discloses a sequential precipitation procedure for the production of catalysts for hydrogenation of edible oils, as defined in the patent in suit.

Hence, also in this case, the claimed solution would not be obvious over the cited art.

4.5.4. None of the further documents on file, such as H2, U7, E6, H9 and U8, teaches or points to a preparation with sequential precipitation and spray-drying for preparing catalysts suitable for the hydrogenation of edible oils. Therefore, the catalysts defined in claim 1 in suit cannot be obvious over the said further documents.

4.6. It follows from the above that the claimed subject-matter is not obvious to a person skilled in the art having regard to the state of the art. Therefore, the subject-matter as defined in claim 1 of the main request involves an inventive step.

4.7. Since the main request is allowable, it is not necessary to consider the auxiliary requests.

5. Reimbursement of the appeal fee

Appellant I requested reimbursement of the appeal fee, asserting that the parties had had no reasonable chance to comment on the claims submitted during the oral proceedings before the Opposition Division, which were limited having regard to the spray-drying step.

In this respect, the Board notes that there is nothing in the minutes of the oral proceedings before the Opposition Division indicating that opponent II had protested against the filing of the main request, or that they had not been in a position to comment on it. In fact, they did comment and provided arguments.

In view of this, the Board finds that opponent II has had adequate opportunity to state his position, so that no procedural violation has taken place. The request for reimbursement of the appeal fee is consequently refused.