* Euro slips as investors watch developments in Catalan situation

* BOJ tankan finds big manufacturers' sentiment best since 2007

* China, several other Asia markets closed for holidays

By Lisa Twaronite

TOKYO, Oct 2 (Reuters) - The dollar started the month on a high note on Monday, underpinned by higher U.S. yields, while the euro came under pressure as investors monitored the aftermath of an independence vote in Spain's Catalonia.

The dollar index, which tracks the greenback against a basket of six major currencies, added 0.3 percent to 93.323 .

Higher U.S Treasury yields helped bolster the greenback. The 10-year U.S. Treasuries yield rose to 2.360 percent in Asian trading compared to Friday's U.S. close of 2.326 percent.

Liquidity was relatively thin on Monday, with China, South Korea, Hong Kong and India and markets closed for public holidays. In Australia, trade was light with Sydney closed for a holiday while Melbourne remained open.

The euro slipped 0.3 percent to $1.1776, as investors nervously watched the situation in Spain, where police used batons and rubber bullets to thwart the Catalan vote on Sunday in a show of force that left hundreds injured.

"With so many regional markets shut in Asia today, it wouldn't be at all strange if the euro made bigger moves later, as Europe comes in," said Kumiko Ishikawa, FX market analyst at Sony Financial Holdings in Tokyo.

The head of Catalonia's regional government opened the door to a potential declaration of independence from Spain.

Against the yen, the dollar rose 0.3 percent to 112.84 .

Data released earlier on Monday showed Japan's big manufacturers were the most confident about the business outlook in a decade in the last quarter, a closely watched central bank survey showed on Monday, a sign the country's economic recovery may be gathering steam thanks to robust global demand.

The figures could also help premier Shinzo Abe as he tries to convince voters in an Oct. 22 election that his "Abenomics" stimulus policies have improved their livelihoods, analysts say.

There are two main directional scenarios for the yen following the election, said Masafumi Yamamoto, chief forex strategist at Mizuho Securities.

"If the results are perceived as a bad outcome for Abe's party, then some investors might view it as the beginning of the end of his 'Abenomics,' meaning the end of the yen-weakening trend," he said.

"But there is another possibility as well, with both parties calling for stimulus steps, which some people think might lead to 'helicopter money,' so then they might sell yen," he said. "Overall, though, dollar/yen is still dominated by U.S. factors."