Department of Environmental Sciences, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, KPK 22060, Pakistan.
Department of Civil Engineering, University of Hail, Hail, Hail Province 55476, Saudi Arabia.
Molecules. 2020 May 1;25(9):2118. doi: 10.3390/molecules25092118.
Waste wood biomass as precursor for manufacturing activated carbon (AC) can provide a solution to ever increasing global water quality concerns. In our current work, derived phosphoric acid-treated AC (MA-AC400) was manufactured at a laboratory scale. This novel MA-AC400 was tested for RO16 dye removal performance as a function of contact time, adsorbent dosage, pH, temperature and initial dye concentration in a batch scale arrangement. MA-AC400 was characterized via scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering (DLS) and fluorescence spectroscopy. MA-AC400 is characterized as mesoporous with BET surface area of 293.13 m g and average pore width of 20.33 Å. pH and Boehm titration confirm the acidic surface charges with dominance of phenolic functional groups. The average DLS particle size of MA-AC400 was found in the narrow range of 0.12 to 0.30 µm and this polydispersity was confirmed with multiple excitation fluorescence wavelengths. MA-AC400 showed equilibrium adsorption efficiency of 97.8% for RO16 dye at its initial concentration of 30 mg L and adsorbent dose of 1 g L. Thermodynamic study endorsed the spontaneous, favorable, irreversible and exothermic process for RO16 adsorption onto MA-AC400. Equilibrium adsorption data was better explained by Langmuir with high goodness of fit (R, 0.9964) and this fitness was endorsed with lower error functions. The kinetics data was found well fitted to pseudo-second order (PSO), and intra-particle diffusion kinetic models. Increasing diffusion constant values confirm the intraparticle diffusion at higher RO16 initial concentration and reverse was true for PSO chemisorption kinetics. MA-AC400 exhibited low desorption with studied eluents and its cost was calculated to be $8.36/kg.
废木材生物质作为制造活性炭 (AC) 的前体，可以为解决日益严重的全球水质问题提供解决方案。在我们目前的工作中，在实验室规模上制造了衍生的磷酸处理的 AC (MA-AC400)。在批处理装置中，作为接触时间、吸附剂剂量、pH、温度和初始染料浓度的函数，测试了这种新型 MA-AC400 对 RO16 染料去除性能。通过扫描电子显微镜、能量色散 X 射线光谱、傅里叶变换红外光谱、动态光散射 (DLS) 和荧光光谱对 MA-AC400 进行了表征。MA-AC400 被描述为具有 293.13 m g 的 BET 表面积和 20.33 Å 的平均孔径的中孔。pH 和 Boehm 滴定法证实了具有酚官能团优势的酸性表面电荷。MA-AC400 的平均 DLS 粒径发现处于 0.12 至 0.30 µm 的狭窄范围内，并且通过多个激发荧光波长证实了这种多分散性。在 RO16 初始浓度为 30 mg L 和吸附剂剂量为 1 g L 的情况下，MA-AC400 对 RO16 染料的平衡吸附效率为 97.8%。热力学研究证实了 RO16 吸附到 MA-AC400 上是自发的、有利的、不可逆的和放热的过程。平衡吸附数据通过朗缪尔方程得到了很好的解释，拟合度很高 (R，0.9964)，并且这种拟合度得到了较低的误差函数的支持。动力学数据很好地符合伪二级 (PSO) 和内扩散动力学模型。增加扩散常数值证实了在较高的 RO16 初始浓度下的内扩散，而 PSO 化学吸附动力学则相反。MA-AC400 对所研究的洗脱剂表现出低解吸性，其成本计算为 8.36 美元/kg。
