Department of Environment Studies, Panjab University, Chandigarh, 160014, India.
Centre for Public Health, Panjab University (PU), Chandigarh, 160025, India.
Environ Sci Pollut Res Int. 2019 Aug;26(24):24516-24531. doi: 10.1007/s11356-019-05563-7. Epub 2019 Jun 23.
Ammoniacal nitrogen is considered as one of the major pollutants of the leachate generated from the landfill site and has the potential to deteriorate the environment as well as health. Considering this, locally available agricultural waste, i.e., sugarcane bagasse ash, was employed as an adsorbent for the removal of ammoniacal nitrogen from landfill leachate. Batch-mode experiments were conducted to see the effect of dose (2-60 g L), pH (2-12), and temperature (20-60 °C) on ammoniacal nitrogen adsorption. Application of sugarcane bagasse ash showed 60% removal of ammoniacal nitrogen (50 mg L strength) at an optimum dose of 20 g L and 180 min of contact time with an adsorption capacity of 0.31 mg g. The Langmuir adsorption model was found to be best fit at 40 °C with R = 0.944, depicting a monolayer coverage of ammoniacal nitrogen onto sugarcane bagasse ash. According to the result, solute uptake rate could be well described by the pseudo-second-order model (R = 0.928), whereas the intraparticle diffusion model and Boyd plot indicated that the overall adsorption rate is governed by the external mass transfer. Thermodynamic studies revealed that adsorption is feasible, spontaneous, and endothermic in nature. Hence, the study shows that sugarcane bagasse ash could turn out to be a cost-effective adsorbent for the removal of ammoniacal nitrogen from leachate.
氨氮被认为是垃圾填埋场渗滤液中的主要污染物之一，它有可能恶化环境和健康。有鉴于此，本研究采用当地易得的农业废弃物——甘蔗渣灰作为吸附剂，用于去除垃圾渗滤液中的氨氮。通过批量实验考察了剂量（2-60 g/L）、pH（2-12）和温度（20-60°C）对氨氮吸附的影响。结果表明，甘蔗渣灰的应用在最佳剂量 20 g/L 和 180 min 接触时间下，可去除 50 mg/L 氨氮强度的 60%，吸附容量为 0.31 mg/g。在 40°C 时，Langmuir 吸附模型拟合度最佳，R=0.944，表明氨氮在甘蔗渣灰上的单层覆盖。根据结果，假二阶模型（R=0.928）可以很好地描述溶质摄取速率，而内扩散模型和 Boyd 图表明，整体吸附速率受外扩散控制。热力学研究表明，吸附是可行的、自发的和吸热的。因此，本研究表明，甘蔗渣灰可能成为一种从渗滤液中去除氨氮的经济高效的吸附剂。
