Robert Allen Knudsen, 77, formerly of Wayne, an Arco Chemical Co. engineer for three decades, died Friday, Oct. 28, of cerebral vascular disease at Devon Senior Living.

Mr. Knudsen went to work for Arco when the company was headquartered in Newtown Square. He traveled to Europe to provide professional support and training for other Arco engineers. After 1998, when the Lyondell Petrochemical Co. acquired Arco from the Atlantic Richfield Co., Mr. Knudsen was transferred to Houston.

He was active in the American Institute of Chemical Engineers, and published several papers on technical topics. He was "greatly admired both personally and professionally by his coworkers," his family said in a tribute.

Born in Chicago to August Knudsen and Grace Biukema, he graduated in 1957 from Chicago Christian High School, and earned a bachelor of science degree from Illinois Institute of Technology and a master of science from Oregon State University, both in chemical engineering.

In 1966, he married Barbara Kuypers, and the couple had two children. In 1980, their 8-year-old daughter, Diane Ruth Knudsen, died in a bicycle-truck collision in Wilmington, where the family lived at that time.

The couple divorced in mid-1980s. She died in 1997.

Mr. Knudsen was a Christian Reformed Church member before becoming a Presbyterian. He enjoyed going to art museums and attending orchestra concerts.

After retiring in 2009, Mr. Knudsen moved to Wayne to be closer to granddaughter Lily Rose Spicer. In the tribute, his family said he will be remembered as "a gentle and sincere man."

Besides his granddaughter, he is survived by a daughter, Cynthia Ann Spicer; a brother; and a sister.

A visitation starting at 1:30 p.m. Saturday, Nov. 12, will be followed by a 2 p.m. memorial service at Washington Memorial Chapel, Route 23, Valley Forge. Burial is in the adjacent chapel cemetery.

Donations may be made to Delaware County Christian School, 462 Malin Rd., Newtown Square, Pa. 19073.