Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, No 999, Xi'an Road, Chengdu, 611756, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Oct;25(29):29256-29266. doi: 10.1007/s11356-018-2906-1. Epub 2018 Aug 17.
Sheep manure biochar (SMB), rabbit faeces biochar (RFB) and pig manure biochar (PMB) prepared by controlled thermal decomposition at 500 °C were used to adsorb methylene blue (MB) in water. Elemental analysis, BET and SEM results showed that the specific surface area, total pore volume and average pore diameter of SMB were 7.59, 4.20 and 1.16 times greater than those of RFB, which were also 12.02, 6.88 and 1.37 times greater than those of PMB respectively. SMB had stronger stability and aromaticity. When the initial concentration of MB was 50 mg L and pH was 11, adsorption achieved equilibrium at approximately 210 min. The adsorption followed pseudo-second-order kinetics (R > 0.96), indicating that liquid film diffusion, surface adsorption and intraparticle diffusion all contributed to the adsorption rate. The results of isothermal adsorption showed that the adsorption performance of SMB was more consistent with a Freundlich model, whereas the performance of RFB and PMB was more consistent with a Langmuir model with a maximum adsorption capacity of 53.68 to 238.31 mg g. Thermodynamic and FTIR studies showed that the adsorption of MB on SMB, RFB and PMB was spontaneous and endothermic, and hydrogen bonds and π-π bonds were closely related to the adsorption process. The results of regeneration show that the optimal number of cycles for SMB, RFB and PMB are 8, 5 and 3, respectively.
采用控制热解在 500°C 下制备的羊粪生物炭（SMB）、兔粪生物炭（RFB）和猪粪生物炭（PMB）来吸附水中的亚甲基蓝（MB）。元素分析、BET 和 SEM 结果表明，SMB 的比表面积、总孔体积和平均孔径分别是 RFB 的 7.59、4.20 和 1.16 倍，也是 PMB 的 12.02、6.88 和 1.37 倍。SMB 具有更强的稳定性和芳香性。当 MB 的初始浓度为 50mgL 和 pH 为 11 时，吸附在大约 210min 时达到平衡。吸附遵循伪二级动力学（R > 0.96），表明液膜扩散、表面吸附和颗粒内扩散都对吸附速率有贡献。等温吸附的结果表明，SMB 的吸附性能更符合 Freundlich 模型，而 RFB 和 PMB 的吸附性能更符合 Langmuir 模型，最大吸附容量分别为 53.68 至 238.31mg g。热力学和 FTIR 研究表明，MB 在 SMB、RFB 和 PMB 上的吸附是自发和吸热的，氢键和π-π键与吸附过程密切相关。再生结果表明，SMB、RFB 和 PMB 的最佳循环次数分别为 8、5 和 3。
