Preparation and characterization of Theobroma cacao pod-modified feldspar composite for possible metal adsorption in wastewater management

Abstract

In this study modified feldspar composite (MFC) was prepared from the combination of Theobroma cacao pod (TCP) and feldspar (FS) using calcination method. The Theobroma cacao pod-feldspar sample was first Na-modified by treatment using 0.1M NaOH solution before calcination in the muffle furnace at 3000C to complete the process of composite preparation. The Theobroma cacao pods (TCP), feldspar (FS) and modified feldspar composite (MFC) were characterized using XRF, X-ray diffraction (XRD), Brunauer Emmett and Teller ( BET) analysis, scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). The results showed that the cation exchange capacity of the modified feldspar composite (30.66 ± 0.21 meq/100 g) was 5 times higher than that of raw feldspar (6.42 ± 0.45 meq/100g). More so, the novel biohybrid material, MFC has a surface area of 53.60 ± 0.3 m2/g and particle size of 105.4 ± 0.18. The XRD patterns revealed that after the modification process, there is only slight shift in the position of some diffraction peaks of feldspar and the composite material indicating the retention of the crystalline properties of the feldspar in the novel composite (MFC). FTIR results showed that some functional groups present in the two starting materials were also available on the surface of the composite (MFC) indicating that the intercalation of TCP biomass into feldspar surface was successful. Owing to its improved cation exchange capacity and eco-friendliness, the modified feldspar composite (MFC) has a good potential application as adsorbent for heavy metals in wastewater treatment besides other industrial explorations.