Despite pressure from his father to enter the family business, Knoblauch in his early 20s opted to study mathematics and science at the University of Berlin.

Knoblauch's doctorate, completed in Berlin in 1847, described valuable experiments that established some of the optical properties of radiant heat (a.k.a.

In an article describing these experiments Knoblauch wrote that experimental facts are "the only permanent things in science", while abstract models are "transitory" and should be treated with caution and kept separate from the facts,[3] a view that Magnus maintained also.

As a researcher and teacher at the University of Marburg, 1849–53, he produced valuable experimental demonstrations about the nature of diamagnetism.

His wife Elisabeth (1827–1855) died on September 12 due to complications from childbirth of their son Johannes, who was born on August 27.