Art collector, businessman and a member of the Drexel family. He was married to Mary J Drexel, Anthony Drexel's sister.
Lankenau collected work from the Barbizon School, including works by Charles-François Daubigny (1817-1878) and Jules Dupré (1811- 1889) as well as paintings by artists of the Düsseldorf Academy such as Andreas Achenbach (1815-1910) and Oswald Achenbach (1827-1905).
According to Art Treasures of America, he owned works by: A. Achenbach, O. Achenbach, G. Bach, A. Baur, G. Bouchmann, J. Brandy, R. Burnier, J. B. A, Clesinger, A. COffa, J.B.C. Corot, C. Daubingny, N. Diaz, E. Ducker, J. Dupre, H.A. Freguson, O.Gebler, E. Grutzner, L. Hartman, Carl Hoff, C. Holmberg, L. Jiminez, C. Jutz, Ludwig Knaus, H. Koekkoek, J. Kopf, W. Kowalski, C. Kroner, C.F. Lessing, L. Lingeman, W.C. Nakken, C. Niczky, J. Noerr, E. Oehme, H.A. Plathner, J.W. Preyer, G. Raggio, A. Rasmussen, J. Ruyten, H. Salentin, H. Savry, A. Scheurenberg, A. Schreyer, A. Siegert, E. Spitzer, E. Steinbruck, A.R. Veron, F. Voltz, A. Windmaier, E. Woutermartens, F. Zandomenechi.