Abner Brenner, 91, an electrochemist who was a retired National Bureau of Standards section chief and past president of the American Chemical Society, died of sepsis Aug. 13 at Suburban Hospital. He lived in Chevy Chase.

Dr. Brenner, who served as society president in the mid-1940s, worked for the Bureau of Standards from 1930 until retiring in 1971. He spent his last 20 years there as the chief of the bureau's electrodeposition section. After leaving the Bureau of Standards, he operated his own laboratory, N-Q Electrochemical Research, now in Chevy Chase, until the time of his death.

During his years with the government, he worked on projects involving methods of depositing metal coatings and of monitoring plating processes. He held 28 patents, including ones involving the plating process and for equipment used for measuring the characteristics of deposited coatings. He also developed a protective coating for acrylic paintings.

Dr. Brenner was the author of nearly 100 technical papers and of the two-volume work "Electrodeposition of Alloys."

He was the recipient of the Commerce Department's highest award, the Gold Medal. He also had received awards from such groups as the American Electroplaters' Society, the Electrochemical Society and the Institute of Metal Finishing. His professional memberships included the Washington Academy of Sciences.

In 1958, he addressed the Russian All-Union Scientific-Technical Conference on Corrosion and Protection of Metals.

Dr. Brenner, who came to Washington when he joined the National Bureau of Standards as a junior chemist, was born in Kansas City, Mo. He was a member of Phi Beta Kappa and a 1929 graduate of the University of Missouri. He received a master's degree in electrochemistry from the University of Wisconsin and a doctorate in electrochemistry from the University of Maryland.

His first wife, the former Sonia Persky, whom he married in 1936, died in 1964. Survivors include his wife of 35 years, the former Marcella Bernstein, of Chevy Chase; four sons from his first marriage, David, of Rockville, Douglas, of Livingston, N.J., Michael, of Birmingham, and Alan, of Grosse Pointe, Mich.; 10 grandchildren; and a great-grandson.