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Mg/Al double layer hydroxides: intercalation with H3[α-PW12O40]•nH2O Hanifa, Yuliza; Palapa, Neza Rahayu
Science and Technology Indonesia Vol 1 No 1 (2016): October
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (288.753 KB) | DOI: 10.26554/sti.2016.1.1.16-19

Abstract

It has been done the intercalation of polyoxometalate H3[α-PW12O40]•nH2O on Mg-Al double layer hydroxide by comparison weight ratio of double layer hydroxides : polyoxometalate H3[α-PW12O40]•nH2O, i.e: 1:1, 1:2, 1:3 and 1: 4. The product of intercalated double layer hydroxide was characterized using FT-IR spectrophotometer, XRD, and TG-DTA analysis. The spectrophotometer results of FT-IR shown the process of intercalation was not optimum for every weight ratio. Characterization using XRD showed the process of intercalation was optimum at a ratio    2:1 that indicated at the area of 11,12o, 22,85o and 34,5o as double layer hydroxide and at the area of 60-63o showed the double layer hydroxide has intercalated with polyoxometalate. The characterization results using TG-DTA analysis at the comparison 2:1 showed loss of OH in the layer at 170 to 220°C and for the decomposition of polyoxometalate H3[α-PW12O40]•nH2O at 300 to 400°C. Keywords:  Double Layer Hydroxide, Intercalation, Polyoxometalate H3[α-PW12O40]·nH2O
Adsorption of congo red using Mg/Al hydrotalcite Said, Muhammad; Palapa, Neza Rahayu
Science and Technology Indonesia Vol 2 No 1 (2017): January
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (769.746 KB) | DOI: 10.26554/sti.2017.2.1.17-21

Abstract

Polyoxometalate H4[α-SiW12O40].nH2O intercalated layered double hydroxide (1:1) was used as adsorbent colored-dye. Polyoxometalate H4[αSiW12O40].nH2O intercalated layered double hydroxide ratio (1:1) was applied as the adsorbent of Congo  red-dye, and produce 51.38 (min-1) of the adsorption rate, for the largest of the adsorption capacity (b) 9.091 mol/g at 70°C, the largest adsorption energy 10.752 kJ/mol at 30°C. The value of the enthalpy (ΔH) and entropy (ΔS) decreased with increasing concentration of Congo  red-dye. Effect adsorption of pH was show the optimal pH at 8 with the amount Congo red absorbed were 47.529 ppm. Keywords: Hydrotalcite, layered double hydroxide, polyoxometalate, intercalated, Congo red, adsorption
Keggin type polyoxometalate H4[αSiW12O40].nH2O as intercalant for hydrotalcite Palapa, Neza Rahayu; Said, Muhammad
Science and Technology Indonesia Vol 1 No 1 (2016): October
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (457.337 KB) | DOI: 10.26554/sti.2016.1.1.25-28

Abstract

The synthesis of hydrotalcite and polyoxometalate H4[αSiW12O40].nH2O with the ratio (2:1), (1:1), (1:2) and (1:3) has been done. The product of intercalation was characterized using FT-IR spectrophotometer, XRD, and TG-DTA. Polyoxometalate H4[αSiW12O40].nH2O intercalated layered double hydroxide was optimised to use as adsorbent Congo red dye. Characterization using FT-IR was not showing the optimal insertion process. The result using XRD characterization was showed successful of polyoxometalate H4[αSiW12O40].nH2O inserted layered double hydroxide with a ratio (1:1) which the basal spacing was expanded from 7,8 Ȧ to 9,81 Ȧ. Furthermore, the thermal analysis was performed using TG-DTA. The result show that the decomposition of polyoxometalate H4[αSiW12O40].nH2O intercalated  hydrotalcite with ratio (1:1) was occured at 80oC to 400oC with a loss of OH in the layer at 150oC to 220oC, and then the decomposition of the compound polyoxometalate H4[αSiW12O40].nH2O at 350oC to 420oC. Keywords: Hydrotalcite, Layered Double Hydroxide, Polyoxometalate, Intercalation
Adsorption of Cobalt (II) on Layered Double Hydroxides (Mg/Al and Ca/Al) In Aqueous Medium : Kinetic and Thermodynamic Aspect Palapa, Neza Rahayu; Taher, Tarmizi; Said, Muhammad; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol 3 No 4 (2018): October
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (688.808 KB) | DOI: 10.26554/sti.2018.3.4.189-194

Abstract

Layered double hydroxides Mg/Al and Ca/Al has been synthesized by co-precipitation method with molar ratio M2+:M3+ (3:1) at pH 10. The synthesized materials were characterized by XRD and FTIR. The materials were used as adsorbent for the removal Cobalt (II) in aqueous solution. The adsorption experiments were studied through some variables adsorption such as variation of contact time, variation of temperature and variation of initial concentration. Kinetic parameters was obtained from variation of contact time. Data was analyzed by pseudo-first-order and pseudo-second-order kinetics models in linear analyses. The kinetic studies showed that the adsorption process more fitted by pseudo-second-order than pseudo-first-order based on coefficient correlation. Isotherm parameters was calculated using Langmuir and Freundlich isotherm models. The adsorption process was spontaneous and endothermic.
KINETIC ADSORPTION OF DIRECT YELLOW ONTO ZN/AL AND ZN/FE LAYERED DOUBLE HYDROXIDES Palapa, Neza Rahayu; Rahayu, Bakri Rio; Taher, Tarmizi; Lesbani, Aldes; Mohadi, Risfidian
Science and Technology Indonesia Vol 4 No 4 (2019): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1109.827 KB) | DOI: 10.26554/sti.2019.4.4.101-104

Abstract

Zn/Al and Zn/Fe layered double hydroxides has successfully synthesized by co-precipitation methods with molar ration 3:1. The samples were characterized using X-Ray Diffraction, Fourier Transform Infrared Spectroscopy and Surface Area using BET method. In this study, Zn/Al and Zn/Fe layered double hydroxides were used to remove direct yellow dye in aqueous solution. The experiments were carried out time variations with the aim of observing the kinetic studies. The results showed that the adsorption of direct yellow onto Zn/Al and Zn/Fe layered double hydroxides based on co-efficient correlation kinetic models more fit using pseudo-second-order than pseudo-first-order.
Intercalation Zn/Cr Layered Double Hydroxides with K3[𝛼-PW12O40]nH2O and K4[𝛼-SiW12O40]nH2O as Adsorbent of Rhodamine-B Ramadhan, Jeri; palapa, neza rahayu; Taher, Tarmizi; Lesbani, Aldes; Mohadi, Risfidian
Science and Technology Indonesia Vol 4 No 4 (2019): October
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2019.4.4.109-114

Abstract

Synthesis of Zn-Cr layered double hydroxide intercalated with polyoxometalate K3[?-PW12O40]nH2O and K4[?- SiW12O40]nH2O was conducted successfully. The characterization of layered double hydroxide intercalated was performed using XRD and FT-IR analyses. After that layered double hydroxide intercalated used as an adsorbent of rhodamine B (RhB) dye. The results show Rhodamine-B (RhB) more effective adsorbed using the Zn-Cr adsorbent K3[?-PW12O40]nH2O than using an intercalated adsorbent K4[?-SiW12O40]nH2O because the distance between the layers is smaller. Study of kinetics showed that the adsorption process is more fits with PSO than PFO based on coefficients correlation. The adsorption process described by Langmuir isotherm models for all adsorbent. The value of enthalpy and entropy shows that the adsorption process was endothermic and negative free energy value was indicated that the process was spontaneous.
Removal of Anionic Direct Dye Using Zn/Al, Zn/Fe and Zn/Cr Layered Double Hydroxides Toward Interlayer Distance Palapa, Neza Rahayu; Taher, Tarmizi; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol 4 No 3 (2019): July
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1299.16 KB) | DOI: 10.26554/sti.2019.4.3.70-76

Abstract

In order to minimize harmful effect of synthetic dye (direct yellow and direct violet) the capacity of Zn/Al, Zn/Cr and Zn/Fe layered double hydroxides of these contaminant was studied in this work. Batch adsorption experiment was conduct to investigate the effect of various operating parameters such as contact time, initial dye concentration and adsorption temperature in order to provide optimal condition in removal synthetic dye. Based on result, the sorption of direct dye onto LDHs followed pseudo-second-order rate model. The equilibrium adsorption data for both direct dye was fitted Freundlich isotherm model
Synthesis and Characterization of Zn/Al, Zn/Fe, and Zn/Cr Layered Double Hydroxides: Effect of M3+ ions Toward Layer Formation Palapa, Neza Rahayu; Saria, Yosi; Taher, Tarmizi; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol 4 No 2 (2019): April
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1267.749 KB) | DOI: 10.26554/sti.2019.4.2.36-39

Abstract

Layered double hydroxides are composed by substitution of metal cation divalent and trivalent. Metal cation divalent and trivalent can be changed. In this work, effect metal cation trivalent (M3+) toward layer formation were studied. Synthesis of LDHs has used co-precipitation methods with molar ratio 3:1 and kept pH at 10. The result of synthesis was characterized by X-ray Diffraction (XRD) and Fourier Transform Infrared (FT-IR) analyses.
Modification Of Zn-Cr Layered Double Hydroxide With Keggin Ion [α-SiW12O40]4- AS Cr(VI) Adsorbent Oktriyanti, Melantina Melan; Palapa, Neza Rahayu; Mohadi, Risfidian; Lesbani, Aldes
Indonesian Journal of Environmental Management and Sustainability Vol 3 No 3 (2019): September
Publisher : ARTS Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (984.079 KB) | DOI: 10.26554/ijems.2019.3.3.93-99

Abstract

Abstract: In this study, synthesis of layered double hydroxide of Zn-Cr and Zn-Cr intercalated with keggin ion [SiW12O40]4- have been carried out. The synthesized material was characterized using XRD, BET, and FTIR. Material of Zn-Cr layered double hydroxide and the intercalation results are used as Cr(VI) ion adsorbent. Factors that influence the adsorption process studied to obtain kinetic and thermodynamic parameters include time, concentration and temperature variation of adsorption. Based on XRD characterization, the distance between layers from 7,53 ? on the Zn-Cr layered double hydroxide before intercalation to 10,26 ? on Zn-Cr layered double hydroxide intercalated with keggin ion [SiW12O40]4-. BET analysis showed that the surface area of both materials increased from 31,638 m2/g to 128,871 m2/g. The result of pH Point Zero Charge measurement for the Zn-Cr layered double hydroxide material is 10 while the Zn-Cr intercalated with keggin ion [SiW12O40]4- material is 8. Based on the kinetics model, adsorption of Cr(VI) ion follows pseudo-second-order model with a linear regression coefficient close to 1. Furthermore, the intercalation of the Zn-Cr intercalated with keggin ion [SiW12O40]4- shows the higher adsorption capacity for the Cr(VI) ion than the Zn-Cr layered double hydroxide as a control. Keywords: adsorption, Cr(VI), keggin ion, layered double hydroxide, Zn-Cr
INTERCALATION ZN/CR LAYERED DOUBLE HYDROXIDES WITH K3[𝛼-PW12O40]NH2O AND K4[𝛼-SIW12O40]NH2O AS ADSORBENT OF RHODAMINE-B Ramadhan, Jeri; Palapa, Neza Rahayu; Taher, Tarmizi; Mohadi, Risfidian; Lesbani, Aldes
Science and Technology Indonesia Vol 4 No 4 (2019): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2019.4.4.109-114

Abstract

Synthesis of Zn-Cr layered double hydroxide intercalated with polyoxometalate K3[?-PW12O40]nH2O and K4[?- SiW12O40]nH2O was conducted successfully. The characterization of layered double hydroxide intercalated was performed using XRD and FT-IR analyses. After that layered double hydroxide intercalated used as an adsorbent of rhodamine B (RhB) dye. The results show Rhodamine-B (RhB) more effective adsorbed using the Zn-Cr adsorbent K3[?-PW12O40]nH2O than using an intercalated adsorbent K4[?-SiW12O40]nH2O because the distance between the layers is smaller. Study of kinetics showed that the adsorption process is more fits with PSO than PFO based on coefficients correlation. The adsorption process described by Langmuir isotherm models for all adsorbent. The value of enthalpy and entropy shows that the adsorption process was endothermic and negative free energy value was indicated that the process was spontaneous.