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Bentonite intercalated organometallic complex as adsorbent of procion red
Full text linkInsertion of bentonite with organometallic compounds [Cr3O(OOCH)6(H2O)3 (NO3)]as adsorbent of procion red with comparison weight ratio of bentonite: organometallic compounds [Cr3O(OOCH)6(H2O)3 (NO3)] i.e.: (2.5:1), (1:1), (1:2) and (1:3) has been done. The results of insertion bentonite were characterized using FT-IR spectrophotometer, XRD, and XRF. Furthermore, the product of optimum insertion was used as an adsorbent of procion red. The spectrogram from FT-IR shows the process of insertion was not optimum for every weight ratio. Characterization using XRD showed the optimum insertion process ratio (1:2) and (1:3) was indicated the presence of diffraction appearing at 2θ region by a shift in the diffraction angles 5.00 and 39o from the original activated bentonite of 20.8o. Characterization using XRF analysis in the ratio (1:3) shows percentage of metal oxide Cr2O3 increase to 82.28%, so at the ratio of 1:3, the process insertion of organometallic compounds into the bentonite has stated success base on its highest percentage. The adsorption process of insertion bentonite organometallic compounds [Cr3O(OOCH)6(H2O)3 (NO3)] ratio (1: 3) shows the magnitude of the rate of adsorption (k) at 0.004 min-1, the adsorption capacity (b), the largest at a temperature of 70oC at 72.99 mol/g, the largest adsorption energy (ΔG) at a temperature of 60oC i.e. 17.05 kJ / mol, the largest enthalpy (ΔH) is 105720.8 kJ/mol, entropy (ΔS) 315 kJ/mol and pH 11 has the biggest value of procion red adsorped, i.e. 33.38 mg/L.
Keywords: Bentonite, Organometallic compound [Cr3O(OOCH)6(H2O)3(NO3)].Adsorption, Procion Re
Preparation, characterization, and thermal stability of B2O3-SiO2
Full text linkPreparation of B2O3-SiO2 compound by inorganic synthesis was carried out. B2O3-SiO2 was characterized by FT-IR spectro-photometer, analysis of crystallinity by XRD, and test of acidity. B2O3-SiO2 was also tested by thermal stability with temperature range at 300-700 ⁰C. The results showed that the FT-IR spectrum of B2O3-SiO2 has some vibrations of B-O, Si-O-Si, Si-O-B stretching, and Si-O-B bending at 1442.8 cm-1, 779.2 cm-1, 925.8 cm-1, and 648.1 cm-1. The X-Ray diffraction pattern results showed that the analysis of B2O3-SiO2 has high crystallinity with two peaks diffraction identified at 26.6⁰ and 20.9⁰. The thermal stability test of B2O3-SiO2 showed that B2O3-SiO2 has high thermal stability with temperature range at 300-700 ⁰C. The results showed that the acidity analysis of B2O3-SiO2 has potential number 122.71 mV so that indicated B2O3-SiO2 was high acidity.
Keywords : boric oxide, silica dioxide, boric silica, B2O3-SiO
Adsorption of congo red using kaolinite-cellulose adsorbent
Full text linkKaolinite was impregnated with cellulose extracted from rubber wood fibers has been done. The product of impregnated kaolinite-cellulose was characterized using FT-IR spectrophotometer. Furthermore, the impregnation results are used as an adsorbent of Congo red. Adsorption of Congo red was also studied the kinetic and thermodynamic parameters. The results of characterization using FT-IR spectrophotometer shows the process of impregnation was successfully conducted. It was indicated that the presence wavenumber at 910.4 - 918.12 cm-1 and 1033.85 cm-1 become 1026.13 cm-1 and the existence of vibration at wavenumber 2931.8 cm-1. The pH of adsorption was adjusted to 4 before the adsorption process. The adsorption process of cellulose impregnated kaolinite shows the rate of adsorption (k) of 0.002 min-1, the adsorption reviews largest capacity (b) at 50 °C was 500 mol/g. The greatest adsorption energy (E) at 40 °C is 11:09 kJ/mol. The enthalpy value (ΔH) and entropy (ΔS) decreased with increasing Congo red dye concentration.
Keywords: kaolinite, cellulose, impregnation, Congo re
Adsorption of congo red using Mg/Al hydrotalcite
Full text linkPolyoxometalate 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, adsorptio
Synthesis and characterization of metal oxides supported keggin type polyoxometalate Rb2K2[-H2SiV2W10O40].nH2O
Full text linkSynthesis of material based on polyoxometalate Rb2K2[γ-H2SiV2W10O40].nH2O with SiO2, TiO2, ZrOCl2, and TaCl5 was carried out to form Rb2K2[γ-H2SiV2W10O40].nH2O-SiO2, Rb2K2[γ-H2SiV2W10O40].nH2O-TiO2 Rb2K2[γ-H2SiV2W10O40].nH2O-ZrOCl2 and Rb2K2[γ-H2SiV2W10O40].nH2O-TaCl5. Materials from preparation were characterized through functional group analysis using FT-IR spectrophotometer, crystallinity analysis using XRD and surface photograph analysis using SEM. The results show that material Rb2K2[γ-H2SiV2W10O40].nH2O was successfully loaded with SiO2, ZrOCl2 and TaCl5. Based on SEM photo Rb2K2[γ-H2SiV2W10O40].nH2O-TiO2 and Rb2K2[γ-H2SiV2W10O40].nH2O-ZrOCl2 were the best material from preparation base on the homogeneity particle distribution. The FT-IR spectrum shows specific wavenumber for nanomaterial Rb2K2[γ-H2SiV2W10O40].nH2O-TiO2 in the range 455-910 cm-1 and Rb2K2[γ-H2SiV2W10O40].nH2O - ZrOCl2 in the range 393.48-1404 cm-1. XRD pattern for material Rb2K2[γ-H2SiV2W10O40].nH2O-TiO2 and Rb2K2[γ-H2SiV2W10O40].nH2O-ZrOCl2 show there is a difference between polyoxometalate Rb2K2[γ-H2SiV2W10O40].nH2O, TiO2 and ZrOCl2. SEM photo analysis of Rb2K2[γ-H2SiV2W10O40].nH2O-TiO2 and Rb2K2[γ-H2SiV2W10O40].nH2O-ZrOCl2 showed that material polyoxometalate with support has a diameter size of particle above 100 nm.
Keywords: Rb2K2[γ-H2SiV2W10O40].nH2O, polyoxometalate, SiO2, TaCl5, TiO2, ZrOCl2
Adsorption of procion red and congo red dyes using microalgae Spirulina sp
Full text linkAdsorption of procion red and congo red dyes using microalgae Spirulina sp was conducted. Spirulina sp was obtained by cultivation and production in laboratory scale. Spirulina sp was used as adsorbent for adsorption of dyes. Adsorption process was studied by kinetic and thermodynamic in order to know the adsorption phenomena. The results showed that kinetically congo red is reactive than procion red on Spirulina sp. On the other hand, thermodynamically procion red was stable than congo red on Spirulina sp which was indicated by adsorption capacity, enthalpy, and entropy.