ASTM D 3943 : 2021

1.1This test method covers the determination of molybdenum in alumina-base catalysts and has been cooperatively tested at molybdenum concentrations from 8 to 18 weight %, expressed as MoO₃. Any component of the catalyst other than molybdenum such as iron, tungsten, etc., which is capable of being oxidized by either ferric or ceric ions after being passed through a zinc-amalgam reductor column (Jones reductor) will interfere.

1.2Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3Many catalysts that contain molybdenum also contain other metals, nickel for example, that may be regulated by the EPA. Go to the material safety data sheet for the catalyst material being analyzed. More information can be found at EPA.gov. Additional information on nickel containing catalysts can be found in Test Method D4481.

1.4This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.