Department of Energy and Resource Engineering, Chosun University, Gwangju 61452, Korea.
Green-Bio Research Facility Center, Seoul National University, Pyeongchang-gun 25354, Korea.
Int J Environ Res Public Health. 2022 Jul 25;19(15):9030. doi: 10.3390/ijerph19159030.
In this study, a cost-effective adsorbent based on sodium alginate (SA) with waste foundry dust (WFD) was fabricated for the removal of methyl red (MR) from aqueous media. However, the utilization of WFD/SA beads to remove anionic dyes (such as MR) from effluents has limitations associated with their functional groups. To improve the adsorption performance, WFD/SA-polyethyleneimine (PEI) beads were formed via PEI crosslinking onto WFD/SA beads, which could be attributed to the formation of amide bonds from the carboxyl and amino groups due to the change of N-H bonds in the reaction. The Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) results indicated that PEI was crosslinked on the WFD/SA via a chemical reaction. In the FTIR spectra of WFD/SA-PEI, peaks of the -COO (asymmetric) stretching vibration shifted to 1598 and 1395 cm, which could be attributed to the hydrogen-bonding effect of the N-H groups in PEI. In the N1s spectrum, three deconvoluted peaks were assigned to N in -N= (398.2 eV), -NH/-NH (399.6 eV), and NO (405.2 eV). WFD/SA-PEI beads were assessed and optimized for aqueous MR adsorption. The WFD/SA-PEI beads showed a high removal efficiency for MR (89.1%) at an initial concentration of 1000 mg/L, and presented a maximum MR adsorption capacity of 672.7 mg/g MR. The adsorption process showed a good fit with the pseudo-second-order kinetic model and the Langmuir adsorption isotherm model. The amino and hydroxyl groups in the WFD/SA-PEI beads facilitate strong hydrogen bonding and electrostatic interactions. Moreover, these WFD/SA-PEI beads were easily recovered after the adsorption process.
在这项研究中，制备了一种基于海藻酸钠（SA）的具有成本效益的吸附剂，该吸附剂利用废铸造砂（WFD），用于从水介质中去除甲基红（MR）。然而，利用 WFD/SA 珠粒从废水中去除阴离子染料（如 MR）存在与它们的官能团相关的限制。为了提高吸附性能，通过 PEI 交联到 WFD/SA 珠粒上形成 WFD/SA-聚乙烯亚胺（PEI）珠粒，这可以归因于由于反应中 N-H 键的变化，羧基和氨基之间形成酰胺键。傅里叶变换红外（FTIR）和 X 射线光电子能谱（XPS）结果表明，PEI 通过化学反应交联在 WFD/SA 上。在 WFD/SA-PEI 的 FTIR 光谱中，-COO（不对称）伸缩振动峰移至 1598 和 1395 cm，这可以归因于 PEI 中 N-H 基团的氢键效应。在 N1s 光谱中，三个解卷积峰被分配给-N=（398.2 eV），-NH/-NH（399.6 eV）和 NO（405.2 eV）中的 N。评估并优化了 WFD/SA-PEI 珠粒用于水溶液中 MR 的吸附。WFD/SA-PEI 珠粒在初始浓度为 1000 mg/L 时对 MR 具有高去除效率（89.1%），并表现出 672.7 mg/g MR 的最大 MR 吸附容量。吸附过程很好地符合准二级动力学模型和 Langmuir 吸附等温线模型。WFD/SA-PEI 珠粒中的氨基和羟基促进了强氢键和静电相互作用。此外，这些 WFD/SA-PEI 珠粒在吸附过程后很容易回收。
