Kariim I, Abdulkareem A S, Isa R O, Tijani J O, Abubakre O K, Usman M O, Ezzat A O, Al-Lohedan H A, Sayed S R M, Egbosiuba T C
Chemical Engineering Department, Federal University of Technology P.M. B. 65 Minna Nigeria
Nanotechnology Research Group, Africa Centre of Excellence for Mycotoxin and Food Safety, Federal University of Technology P. M. B. 65 Minna Nigeria.
RSC Adv. 2024 Aug 19;14(36):26016-26031. doi: 10.1039/d4ra04313h. eCollection 2024 Aug 16.
The refinery industry has witnessed tremendous activity aimed at producing petrochemicals for the benefit of the teeming populace. These activities are accompanied by the discharge of wastewater containing chemical substances and elements that have negative impacts on the ecosystem. The presence of phenol and cyanide contaminants in refinery wastewater poses serious health hazards to humans, necessitating their removal. In this study, boron oxide-doped multi-walled carbon nanotubes (BO/MWCNTs) and titanium boride-doped MWCNT (TiB/MWCNTs) nanoadsorbents were prepared a wet impregnation method and characterized using High-Resolution Transmission Electron Microscopy (HR-TEM), X-Ray Diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS). HR-TEM images depict the nanostructure of the nanoadsorbent, the presence of doped materials, and the internal, external, and wall thickness of BO/MWCNTs and TiB/MWCNTs nanoadsorbents. XRD results indicate that the nanomaterials were monocrystalline with average crystallite sizes of 22.75 nm and 16.79 nm for BO/MWCNTs and TiB/MWCNTs, respectively. The formation of BO and TiB was observable in the results obtained from the XPS at the binding energy of 192 and 193.1 eV, respectively. The application of the produced BO/MWCNTs and TiB/MWCNTs nanoadsorbents for the removal of phenol and cyanide from refinery wastewater was explored in a batch adsorption system. The effects of contact time, adsorbent dosage, and adsorption temperature were investigated. To the best of our knowledge, the incorporation of BO and TiB in MWCNTs resulted in the highest adsorption capacities for phenol and cyanide from aqueous solutions. The highest percentage removal of 100% for phenol and 99.06% for cyanide was observed for the TiB/MWCNTs nanoadsorbent at a residence time of 70 minutes, a temperature of 60 °C, and 0.3 g of adsorbent. The isotherm models show that cyanide and phenol removal obeyed the Langmuir isotherm, indicating monolayer adsorption over BO/MWCNTs nanoadsorbent. Furthermore, cyanide and phenol removal depict multilayer adsorption on the TiB/MWCNT nanoadsorbent. The research shows that BO/MWCNTs are proficient in cyanide sorption, while TiB/MWCNT favors phenol sorption due to their respective adsorption capacities.
炼油行业开展了大量活动，旨在生产石化产品以造福大量民众。这些活动伴随着含有对生态系统有负面影响的化学物质和元素的废水排放。炼油废水中苯酚和氰化物污染物的存在对人类构成严重健康危害，因此必须将其去除。在本研究中，采用湿浸渍法制备了氧化硼掺杂的多壁碳纳米管（BO/MWCNTs）和硼化钛掺杂的多壁碳纳米管（TiB/MWCNTs）纳米吸附剂，并使用高分辨率透射电子显微镜（HR-TEM）、X射线衍射（XRD）和X射线光电子能谱（XPS）对其进行了表征。HR-TEM图像描绘了纳米吸附剂的纳米结构、掺杂材料的存在以及BO/MWCNTs和TiB/MWCNTs纳米吸附剂的内部、外部和壁厚。XRD结果表明，纳米材料为单晶，BO/MWCNTs和TiB/MWCNTs的平均微晶尺寸分别为22.75 nm和16.79 nm。从XPS获得的结果中，分别在192和193.1 eV的结合能处观察到了BO和TiB的形成。在间歇吸附系统中探索了所制备的BO/MWCNTs和TiB/MWCNTs纳米吸附剂对炼油废水中苯酚和氰化物的去除效果。研究了接触时间、吸附剂用量和吸附温度的影响。据我们所知，在多壁碳纳米管中掺入BO和TiB导致从水溶液中去除苯酚和氰化物的吸附容量最高。在停留时间为70分钟、温度为60°C和吸附剂用量为0.3 g的条件下，TiB/MWCNTs纳米吸附剂对苯酚的最高去除率为100%，对氰化物的最高去除率为99.06%。等温线模型表明，氰化物和苯酚的去除遵循朗缪尔等温线，表明在BO/MWCNTs纳米吸附剂上为单层吸附。此外，氰化物和苯酚的去除在TiB/MWCNT纳米吸附剂上表现为多层吸附。研究表明，BO/MWCNTs擅长氰化物吸附，而TiB/MWCNT由于其各自的吸附能力更有利于苯酚吸附。
