Calcination on Ca-Mg-Al Hydrotalcite from Brine Water and Its Characterization

Abstract

<p>The study of calcination treatment at 450°C on Ca-Mg-Al-hydrotalcite from brine water has been investigated. Characterization by XRD shows that Ca-Mg-Al hydrotalcite compound has found hydrotalcite phase and another phase such as Mg(OH)<sub>2</sub>, Al(OH)<sub>3</sub> and CaCO<sub>3</sub>. These results are confirmed by the presence of hydroxyl groups, M-O and M-OH groups (M is Mg, Ca and Al) at wavenumber region around 3464.35 cm<sup>-1</sup>, 447.50 cm<sup>-1</sup> and 531.41 cm<sup>-1</sup>. The calcination effect on Ca-Mg-Al hydrotalcite compounds at 450ºC being led to changes in structure become an metal oxide such as MgO, CaO, Al<sub>2</sub>O<sub>3</sub>, MgAl<sub>2</sub>O<sub>4</sub> and CaCO<sub>3</sub>. These results are confirmed from decreasing on the absorption peak of M-OH group at wavenumbers region around 531.41 cm<sup>-1</sup> and 786.99 cm<sup>-1</sup> and widening of the absorption region at 500-900 cm<sup>-1</sup>. Consequently, the calcination treatment successfully increased the surface area of Ca-Mg-Al hydrotalcite compounds from 97.4 m<sup>2</sup>/g to 156.826 m<sup>2</sup>/g. Morphology of Ca-Mg-Al hydrotalcite changes the shape from a big to be small shape and the particle size distribution of 0-0.25 μm into 0-1 μm. Thermal analysis showed changes in the structure of hydrotalcite into oxide begins at a temperature of 265°C and started to become oxide completely after the temperature reaches 428°C.</p>

Application of the Composite Hydrotalcite (Mg/Al)/Chitosan as Adsorbent for the Treatment of Raw Water of Municipal Waterworks PDAM Bandarmasih

“…However, along with the increase in pH value, the higher the amount of the dye absorbed by hydrotalcite (Mg/Al)/chitosan dose decreases because the effect of high pH is assumed to be positively hydrotalcite (Mg/Al)/chitosan where the real properties diminish. pH (Heraldy, 2017) Adsorption can be influenced by several parameters, namely pH, reaction time, adsorbent dose and temperature (Zubair, 2017). Table 3 shows changes in turbidity of the solution after and before reacting with hydrotalcite (Mg/Al) + chitosan for 24 hours.…”

KONVERSI MINYAK BIJI KAPUK MENJADI BIODIESEL MENGGUNAKAN KATALIS CaO/HTC

“…CaO adalah katalis heterogen dasar yang paling berkembang, namun penggunaan CaO sebagai katalis memiliki kerugian, yaitu ion oksigen (O 2-) pada permukaan mudah membentuk ikatan hidrogen dengan metanol atau gliserol. Salah satu solusi untuk mengatasi masalah tersebut adalah CaO perlu didukung oleh logam aktif [13][14][15]. Sedangkan senyawa hydrotalcite adalah lapisan hidroksida ganda yang termasuk dalam kelas lempung bermuatan positif pada lapisannya.…”

Hydrotalcite Mg/Al-NO3 from Sea Water as Adsorbent of CU2+ and Cr6+ Metals

“…The low intensity of d 003 formed can be made possible due to the presence of remaining calcium ions, and precursors in sea water that might react, thus inhibiting the formation of hydrotalcite-like, which results in very low crystallization of Hydrotalcite Mg/Al-NO 3 [3]. The synthesis process shows that metal hydroxide compounds have been formed, these metal hydroxide compounds are Mg(OH) 2 The cause of the emergence of unwanted new peaks in the Hydrotalcite Mg / Al-NO3 sample is also influenced by the presence of mother liquid when left for 24 hours [4]. Hydrotalcite Mg/Al-NO 3 which was left for a long time in water produced a higher crystallization rate compared to hydrotalcite Mg / Al-NO 3 which was left in the mother liquor [9].…”

“…Mineral Hydrotalcite is a double-layered hydroxide that has a negatively charged layer with cations on the interlayer [4]. Anionic clays such as hydrotalcite are less abundant in nature than cationic clays, but anionic clays are easily synthesized.…”