Highlights Use of aluminum chloride as an amendment to beef pen surface material lowered pH, which lowered ammonia emissions. Use of aluminum chloride as an amendment lowered cumulative carbon dioxide, methane, and nitrous oxide emissions. Use of aluminum chloride as an amendment did not change nitrogen or sulfur concentrations in pen surface material. Application of 5%–10% (g g-1 as-is) aluminum chloride may replace 5%–10% aluminum sulfate as a pen surface amendment. ABSTRACT. Pen surface amendments are a tool that beef producers can use to reduce emissions and increase nutrient retention in manure. Previous studies demonstrated that aluminum sulfate (alum) could effectively lower ammonia (NH 3 ) emissions but caused increased sulfide emissions. An alternative to alum is aluminum chloride (AlCl 3 ). The objective of this study was to determine if the addition of AlCl 3 to beef pen surface material (PSM) could lower NH 3 losses while also lowering CO 2 , N 2 O and CH 4 emissions. Aluminum chloride was added to pans containing 3 kg of PSM and 3 kg of water at a rate of 0%, 2.5%, 5%, and 10% (g g -1 as-is) of the PSM mass, and emissions were measured for 21 days. The addition of AlCl 3 to PSM lowered (p 0.01) the pH to 5.8 – 7.2 compared to untreated PSM (8.2). Nitrogen and sulfur content of the PSM was not affected by AlCl 3 treatment (p = 0.14). Cumulative NH 3 emissions decreased (p 0.01) as AlCl 3 inclusion increased and were 87.3, 60.5, 33.0, and 20.2 kg ha -1 for the 0%, 2.5%, 5%, and 10% AlCl 3 treated PSM, respectively. Cumulative CO 2 , CH 4 , and N 2 O emissions also decreased linearly as the inclusion rate of AlCl 3 increased. Aluminum chloride appears to be a promising option for beef feedlot producers to reduce emissions from the pen surface. Keywords: Aluminum chloride, Amendments, Ammonia, Beef, Carbon dioxide, Methane, Nitrous oxide.
Spiehs et al. (Thu,) studied this question.