US bankruptcy claims trading at 18-month low

* Number of claims traded lowest since July 2009

* Value of claims traded rises 35 pct

WILMINGTON, Del. Feb 22 (Reuters) - The number of U.S. bankruptcy claims that traded in January fell to the lowest level since July 2009 as more companies emerged from Chapter 11, according to data released on Tuesday.

However, the value of the claims traded rose 35 percent from December to $2.55 billion, according to SecondMarket, which runs a bankruptcy claims trading marketplace.

The increased value was due in part to a spurt of large claims related to the Mesa Air Group Inc bankruptcy, with 39 claims traded worth $170.1 million.

In total, 636 claims traded, down from 687 claims traded in December. It was the lowest number of claims traded since 592 claims were transferred in July 2009.

Bankruptcy-claims trading allows creditors with claims against bankrupt companies sell their interests to investors before the conclusion of a bankruptcy case.

As it does nearly every month, the largest bankruptcy in U.S. history, Lehman Brothers Holding Inc (LEHMQ.PK), led with 236 claims traded, totaling $2.19 billion.

Other actively traded bankruptcies included companies that are being liquidated -- Circuit City Stores Inc, Lack's Stores Inc and Cabrini Medical Center -- as well as Tronox Inc TRXAQ.PK, a chemical company that recently emerged from bankruptcy protection.

Chemical company W.R. Grace & Co (GRA.N), which is expected to emerge soon from its 10-year stay in bankruptcy protection, was also among the most actively traded claims. (Reporting by Tom Hals; editing by Gunna Dickson)