At least one more potential buyer lined up for insolvent refiner Petroplus
on Thursday with private equity group Goldsmith registering interest in all five of its plants.

Swiss-based Petroplus, Europe's largest independent refinery by capacity, is filing for insolvency after battling with high debt and poor refining margins.

The company was forced to close three of its refineries, including Petit Couronne in France, after lenders froze credit lines late in December.

Goldsmith, already a shareholder in Petroplus through a fund, said it had registered its interest with Petroplus' administrators in Germany, Britain and Switzerland.

Petroplus' refinery businesses in Germany, Britain and Switzerland, but also in France and Belgium are sustainable and interesting, despite the current difficulties in this sector, Goldsmith Group said in a statement.

Goldsmith plans to carry out due diligence on parts of Petroplus' business in Belgium and France, it said.

A spokesman for the administrators of Petroplus' Ingolstadt refinery in Germany declined to comment on possible investors in the plant.

French Energy Minister Eric Besson told France Info radio there were more potential buyers for Petroplus' French refinery at Petit Couronne.

Swiss investment vehicle Gary Klesch Group said last week it was considering purchasing the French plant, which stopped production last month, and possibly other refineries owned by Petroplus.

Besson said he hoped he could announce the restart of the refinery within the next 15 days.

The company's UK refinery at Coryton has attracted more than 40 interested parties, its administrator said on Thursday.

There have been over 40 expressions of interest from the speculative to the highly credible, Katherine Howbrook, a spokeswoman for PwC, said.

DOUBTS

Goldsmith has a track record of turning around ailing companies. Founded by German businessman Clemens J. Vedder in 2007, Goldsmith dropped out of a bidding race in 2009 for German retailer Metro's department store chain Kaufhof.

Poor or negative margins have forced several European refiners to put plants on the market and some have been unable to find buyers even at rock-bottom prices.

Finding a buyer for Petroplus' refineries would help avoid shutting down the sites, which entails high costs.

Industry analysts said they doubted private equity groups would be able to turn around Petroplus, saying the problems facing European refiners were structural and had defeated even the biggest oil companies such as the oil majors.

The majors could not make money out of those assets and now you have some private equity groups, be it Klesch or Goldsmith, that supposedly can make it better. I doubt it very much, said Olivier Jakob, energy analyst at consultancy Petroplus.

In the long term, those refineries need somebody involved in the oil trade - a supplier from ex Russian republics or Asia, not just a financial group that just buys something distressed and then tries to sell it two years afterwards.

Shares in Petroplus, which have plunged since lenders froze credit lines in late December, were trading 52 percent higher at 1.16 Swiss francs by 10:23 a.m. British time.

(Additional reporting by Sophie Louet and Pascal Schmuck in Paris, and Zaida Espana and Ikuko Kurahone in London; writing by Christopher Johnson, editing Jason Neely)