Jun Kwong Chia, Abdul Raman Abdul Aziz, Buthiyappan Archina
Department of Chemical Engineering, University of Malaya 50603 Kuala Lumpur Malaysia
RSC Adv. 2020 Jun 24;10(40):24079-24094. doi: 10.1039/d0ra03307c. eCollection 2020 Jun 19.
This study investigated the potential of palm kernel shell (PKS) as a biomass feed for adsorbent production. This work aims at synthesizing green adsorbent from activated PKS by integrating iron oxide and zeolite. The newly developed adsorbents, zeolite-Fe/AC and Fe/AC, were analyzed for surface area, chemical composition, magnetic properties, crystallinity, and stability. The adsorbent efficiency in removing effluent from the palm oil mill was evaluated. The influence of operating parameters, including adsorbent dosage, HO, reaction time, and initial solution pH for adsorption performance was studied. The Fourier transform infrared analysis revealed that the adsorbents contain functional groups including OH, N-H, C[double bond, length as m-dash]O and C[double bond, length as m-dash]C, which are essential for removing pollutants. The SEM-EDX analysis shows holes in the adsorbent surface and that it is smooth. The adsorption study revealed that under optimized conditions, by using 4 g L of adsorbent and 67.7 mM HO, zeolite-Fe/AC was able to remove 83.1% colour and 67.2% COD within 30 min. However, Fe/AC requires 5 g L of adsorbent and 87.7 mM to remove 86.8 percent and 65.6 percent, respectively. This study also showed that zeolite-Fe/AC has higher reusability compared to Fe/AC. Among Freundlich and Temkin models, the experimental data were found to be best fitted with the Langmuir isotherm model. The kinetic analysis revealed that for both adsorbents, the adsorption process fitted the pseudo-second-order model ( = 0.9724). The finding reflects monolayer adsorption of zeolite-Fe/AC and Fe/AC. This study thus demonstrates the applicability of low-cost green adsorbents produced from PKS to treat oil refinery effluent and other recalcitrant wastewaters.
本研究调查了棕榈仁壳（PKS）作为生物质原料用于生产吸附剂的潜力。这项工作旨在通过将氧化铁和沸石结合，从活化的PKS合成绿色吸附剂。对新开发的吸附剂沸石-Fe/AC和Fe/AC进行了表面积、化学成分、磁性、结晶度和稳定性分析。评估了吸附剂去除棕榈油厂废水的效率。研究了操作参数（包括吸附剂用量、过氧化氢、反应时间和初始溶液pH值）对吸附性能的影响。傅里叶变换红外分析表明，吸附剂含有OH、N-H、C=O和C=C等官能团，这些官能团对于去除污染物至关重要。扫描电子显微镜-能谱分析显示吸附剂表面有孔洞且表面光滑。吸附研究表明，在优化条件下，使用4 g/L的吸附剂和67.7 mM的过氧化氢，沸石-Fe/AC能够在30分钟内去除83.1%的色度和67.2%的化学需氧量。然而，Fe/AC需要5 g/L的吸附剂和87.7 mM才能分别去除86.8%和65.6%。本研究还表明，沸石-Fe/AC比Fe/AC具有更高的可重复使用性。在Freundlich模型和Temkin模型中，实验数据被发现最符合Langmuir等温线模型。动力学分析表明，对于两种吸附剂，吸附过程均符合准二级模型（R² = 0.9724）。这一发现反映了沸石-Fe/AC和Fe/AC的单层吸附。因此，本研究证明了由PKS生产的低成本绿色吸附剂在处理炼油厂废水和其他难处理废水方面的适用性。
