Abstract The development of low-cost animal bedding materials for ammonia (NH3) mitigation in livestock facilities is highly desirable from both environmental and waste management perspectives. In this study, we developed an air oxidation method as a simple but effective approach to increase the NH3 adsorption capacity of relatively ubiquitous bituminous coal (BC). The BC samples were oxidized in air at a range of temperatures, from 100 to 550 °C, and the highest NH3 adsorption was observed from the BC modified at 300 °C, with an 11-fold increase (49.7 mg g-1) compared with the initial BC. Samples were characterized using microscopy, BET, FT-IR, XPS, and Boehm titration. The results indicated that NH3 adsorption was dominated by the acidic surface functional groups generated by air oxidation. Ammonium ion (NH4+) adsorption was described by the Langmuir adsorption isotherm and the modified BC retained 5 times more NH4+ than the initial BC. These findings provide insights for the modification of coal materials for the capture of NH3 by simple air oxidation and show promise for future utilization of modified BC for mitigation of NH3 emissions from intensive livestock systems.

中文翻译：

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空气氧化改性烟煤以增加氨捕获

摘要 从环境和废物管理的角度来看，开发用于畜牧设施中氨 (NH3) 缓解的低成本动物垫料材料是非常可取的。在这项研究中，我们开发了一种空气氧化方法，作为一种简单但有效的方法来提高相对普遍存在的烟煤 (BC) 的 NH3 吸附能力。BC 样品在空气中在 100 到 550 °C 的温度范围内被氧化，在 300 °C 改性的 BC 中观察到最高的 NH3 吸附，相比之下增加了 11 倍（49.7 mg g-1）与最初的 BC。使用显微镜、BET、FT-IR、XPS 和 Boehm 滴定法对样品进行表征。结果表明，NH3 吸附以空气氧化产生的酸性表面官能团为主。铵离子 (NH4+) 吸附由 Langmuir 吸附等温线描述，改性 BC 保留的 NH4+ 是初始 BC 的 5 倍。这些发现为改变煤材料以通过简单的空气氧化捕获 NH3 提供了见解，并显示了未来利用改性 BC 来减少集约化畜牧系统中 NH3 排放的前景。