3M Co. has completed its $1 billion purchase of Polypore’s Separations Media business and as a result lowered its earnings guidance for the year.

The Maplewood-based conglomerate said Wednesday it expects full-year 2015 earnings to be $7.73 to $7.93 per share. It previously forecast $7.80 to $8 a share.

With Polypore’s Separations Media business, 3M gains an ultra-filtration expert known for its ability to remove tiny microscopic particles from water, blood and other liquids. The business generates about $210 million in annual sales. It is expected to dilute 2015 earnings by 3 cents per share.

3M shares rose 3.7 percent, or $5.08, to close at $142.72 Wednesday.

The completion of the acquisition by 3M, marked just one part of the process involving Polypore’s parent. North Carolina-based Polypore International also announced Wednesday that it has sold the remaining portion of itself to Japan-based Asahi Kasei for about $2.2 billion.

The Polypore Separations Media buy is one of two large acquisitions by 3M this year.

In June, 3M announced its largest acquisition — the $2.5 billion purchase of Bloomington-based Capital Safety. The company generates about $430 million a year making rugged harnesses and other safety equipment for workers in the construction, drilling and mining industries. That acquisition closed on Aug. 3.

3M will announce third-quarter results on Oct. 22.