* Nearly 10 potential buyers have come forth-minister
* Local minister does not deny SOCAR interest
By Emma Farge
NEUCHATEL, Switzerland, Jan 30 (Reuters) - Switzerland's Cressier refinery, owned by ailing independent oil firm Petroplus, has attracted as many as 10 interested parties, Thierry Grosjean, economy minister of the Swiss canton of Neuchatel, told Reuters on Monday.
Petroplus is filing for insolvency after battling with high debt and poor refining margins, leaving the fate of five European plants unclear.
"I'll say that there are between five and ten [interested parties]. More like ten, than five," Grosjean said of the Swiss refinery.
Asked to confirm speculation that Azeri state oil firm SOCAR was among the potential bidders for Cressier, Grosjean said: "There's no smoke without fire. It's not false."
The Azeri company is seen as a likely candidate as it is has previously expressed interest in the European downstream and because Azeri crude oil accounts for around a third of Swiss imports.
Also, SOCAR already has a foothold in the Alpine country through its its Geneva-based trading arm.
But the wide interest in the plant comes as a surprise at a dismal time for the European crude processing industry where falling demand and strict environmental regulations have crushed margins. Cressier, which employs some 250 people, was Petroplus' least profitable plant in the third quarter.
Several companies have assets on the market but even rock-bottom prices have failed to attract bidders for some assets.
Shares in Petroplus were up 24 percent to 0.31 francs at 1425 GMT, and have almost doubles since opening at 0.16 francs on Friday, their lowest level ever.
But prices on the group's $1.75 billion in bonds have hardly budged, trading between 28 and 31 percent of par, according to Reuters data, implying bondholders are less optimistic than stockholders that a sale of the company's refineries could increase the bankrupt company's residual value.
Grosjean did not say whether the potential buyers were interested in keeping the refinery running or converting it into a storage terminal, but expressed his preference for the former.
"What we prefer is that the refinery continues. Later, we can study other possibilities," he said.
Cressier was shut two weeks ago after Petroplus failed to source crude fresh supplies.
Switzerland now only has one functioning refinery owned by Libya's Tamoil, forcing it to raise imports of oil products from France, Belgium and Germany.