Influence of phosphonation and phosphation on surface acid–base and morphological properties of CaO as investigated by in situ FTIR spectroscopy and electron microscopy

Characterization of crystalline phases of bone ash

“…It is observed from the FTIR data that the observed bands are in well matched position representing the phosphate group as found in previous investigation [Zaki et al 2006, Tas 2000, Xu et al 2001 where the author also observed the presence 655 -548 cm -1 respectively. A small peak at band position 1458.1 cm -1 could be due to the CO 3 2-group.…”

Characterization of Activated Carbon from Eggshell Membranes Prepared Using Sodium Acetate and Zinc Metal Activation

“…Especially, the spectrum of CH 3 COONa-DESMAC prepared at 600°C (Fig. 1f) shows peaks only at 1431 cm −1 (strong) and 875 cm −1 (very weak) which are due to CO 3 2-species of calcite (Zaki et al, 2006). At 400-500°C, the FTIR spectra of CH 3 COONa-DESMACs also contain peaks at 1110 cm −1 , which are attributed to C-O and C-N (Baláž, 2014;Park et al, 2016).…”

“…This results in the decrease of the percent yield of carbonized products as well as the activated products ( Table 1). The peak at 1431 cm −1 is attributed to CaO (Zaki et al, 2006), as well as C=C stretching of aromatic rings (Nasrollahzadeh et al, 2016). A new peak is observed in CDESM after carbonization at 500-600 °C at 712 cm −1 (very weak).…”

“…These peaks remaining after activation at 600°C are also attributed to CO 3 2-of calcite. It should be noted that calcite is usually completely decomposed into CaO above 700°C (Zaki et al, 2006). However, the peaks of C=C, Na-O and C-O stretching (Magdziarz et al, 2016) are also located at 1431 cm −1 , which has caused the peak at 1431 cm −1 to remain with high intensity for all activated products.…”

“…1. Figure 1a shows that the FTIR spectrum of CDESM prepared at 400°C contains peaks at 3367 cm −1 (N-H bonds or C-O asymmetric stretching), 2919 cm −1 (C-H bonds in = C-H and = CH 2 groups), 1760 cm −1 (C=O stretching vibration in carboxylic groups), 1650 cm −1 (amide C=O stretching), 1431 cm −1 (CaO, C=C) and 712 cm −1 ( 2 3 CO − of calcite) (Mami et al, 2008;Baláž et al, 2016;Tan et al, 2015;Botomé et al, 2017;Zaki et al, 2006;Tsai et al, 2006). It contains features that can be attributed to amines, amides, CaCO 3 , = C-H and =CH 2 , which remained in CDESM after preparation at 400°C.…”