Coprecipitation Preparation of Cu/Zn/Al-Hydrotalcite-Like Compound for Copper Removal from Electroplating Wastewater

Abstract

Cu/Zn/Al-hydrotalcite-like compound (Cu/Zn/Al-HTlc) was prepared by the coprecipitation method with ZnII, AlIII cations solution, and electroplating wastewater containing CuII cation. The preparation conditions of Cu/Zn/Al-HTlc were optimized. The metal ion pollutants removal effect and iodide maximum adsorption capacity of Cu/Zn/Al-HTlc were also studied. The physicochemical properties of the Cu/Zn/Al-HTlc were analyzed by X-ray diffraction, FTIR, SEM, N2 adsorption-desorption isotherms, and TG-DTG. The results showed that Cu/Zn/Al-HTlc should be prepared with the ZnII-AlIII molar ratio of 1.5 : 1, pH = 11, and aged at room temperature for 0.5 d. Structural analysis showed that the Cu/Zn/Al-HTlc was a layered compound. CuII and other metal ion pollutants can also be successfully removed from electroplating wastewater in the preparation process of Cu/Zn/Al-HTlc and reached Chinese National Emission Standard (GB 21900-2008). The optimal adsorption condition of calcinated Cu/Zn/Al-HTlc for iodide was as follows: the solid-liquid ratio was 1 : 250, the pH value was 8, and the adsorption process was carried out at 25°C for 30 min. The saturated adsorption capacity reached 1000 mg·g−1 at the optimal adsorption condition. The main reason for this high-saturated adsorption capacity of Cu/Zn/Al-HTlc was that iodide penetrated into the layered structure of Cu/Zn/Al-HTlc by physical adsorption and CuII undergoes a specific redox reaction, producing CuI. Hence, coprecipitation synthetic technology and prepared Cu/Zn/Al-HTlc could be potentially used for electroplating wastewater treatment.

Enhanced Photocatalytic Degradation of Rhodamine-B under Led Light Using CuZnAl Hydrotalcite Synthesized by Co-Precipitation Technique

“…Therefore, the H and CuH-n materials preserved the hydrotalcite structure. However, the peak height of the characteristic peaks of hydrotalcite structure at the planes of (003), (009) and (110) decreased with the increasing proportion of Cu 2+ in the material [2,7]. Based on the distance values (d) between the layers of the hydrotalcites at the plane of (003) and (110), the a and c parameters were obtained, where the a parameter represents the cation-cation distance in the brucite layer and a = 2.d 110 .…”

“…ZnAl hydrotalcite materials have been of significant interest to researchers and scientists. The precursors used to synthesize these materials are also highly diverse, ranging from nitrate, chloride and sulfate salts with molar ratios of Zn 2+ /Al 3+ of 2:1; 3:1 and 4:1, respectively [1][2][3][4][5]. The XRD analysis results show that the Zn 2+ /Al 3+ molar ratios of approximately 2:1 and 1.5:1 were the most suitable for the structure of LDHs [1] and CuZnAl material [2].…”

“…The precursors used to synthesize these materials are also highly diverse, ranging from nitrate, chloride and sulfate salts with molar ratios of Zn 2+ /Al 3+ of 2:1; 3:1 and 4:1, respectively [1][2][3][4][5]. The XRD analysis results show that the Zn 2+ /Al 3+ molar ratios of approximately 2:1 and 1.5:1 were the most suitable for the structure of LDHs [1] and CuZnAl material [2]. The ZnAl materials were used as the modification substrate by various agents (e.g., Cu, Ti and Eu), as well as organic composes (e.g., EDTA and EDDS) [6,7].…”

“…For instance, MgCuAl hydrotalcites have been successfully synthesized according to the molar ratios of Cu 2+ of 0; 0.07; 0.14. 0.21; 0.28; and 0.35 (total molars of Cu 2+ and Mg 2+ to Al 3+ of 0.7:0.3) for the purpose of oxidizing styrene into styrene oxide and benzaldehyde [8]; whereas CuZnAl hydrotalcites were used for the adsorption of Cu 2+ ions in electroplating wastewater [2].…”

A Comparative Investigation of Cu (II), Ni (II) and Molasses Sucrose Effects on the Growth of Candida Yeasts and Metal Bioaccumulation

“…Candida species, a member of the yeast family, are one of the most popular microorganisms due to satisfying biosorption performance (Muter et al 2002). It has been found that different Candida species such as Candida utilis, Candida tropicalis, Candida membranaefaciens and Candida lipolytica can e ciently bioaccumulate heavy metals under various experimental conditions, and the metal uptake behaviors of the yeasts are different (Aksu and Dönmez 2003;Bai et al 2019;Yin et al 2008). The monod equation provides a simple model for describing the growth of a cell in a given nutrient media.…”