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Impregnation of bentonite with cellulose as adsorbent of congo red
Full text linkThe process of bentonite impregnation with cellulose has been studied. Cellulose extracted from rubber wood and clay from natural bentonite was activated. The impregnation process is performed using thiourea as impregnant agent. The impregnation results were characterized by using FT-IR spectrophotometer then the material was used as congo red dye adsorbent. Factors affecting the adsorption process were studied by kinetic parameters and thermodynamic parameters. The FTIR results indicate the impregnation process was succesfully conducted the characterization by FTIR indicated resources of typical absorption of the hydroxyl (OH) and vibrational (-CH) vibration function groups as specific groups of cellulose Appearing at wave numbers 3464.15 cm-1 and 2368.59 cm-1 from impregnated material. Vibration Si-O-Si and Al-O-Si as bentonite-specific strands groups Appear at 1465.9 cm-1 and 609.51 cm-1 wavenumbers in the impregnated spectra. The adsorption thermodynamic study showed that the adsorption and adsorption capacity of the cellulose-impregnated bentonite adsorbent reached the optimum point at 50 ° C at 43.47 mol / g and energy of 11.62 kJ mol. The optimum enthalpy (ΔH) of cellulose bentonite was 143.13 kJ/mol and the minimum entropy (ΔS) at concentration of 40 mg/L was 0.207 kJ/mol.
Keywords: Bentonite, cellulose, impregnation; adsorption; Congo re
Removal lead (Pb) and mercury (Hg) from juaro fish (Pangasius polyuranodon) using citric acid from pineapple extract (Ananas comosus) as chelating agent
Full text linkAn assessment of dietary risk of heavy metals exposure to human is important since it is the main of exposure. The aim of study to measure the contamination of lead and mercury in juaro fish meat and the effort to reduce contaminations using citric acid from pineapple extract as a chelating agent. Samples was soaked and boiled in citric acid extract at concentration 50%, 75 %, 100 % for, 15 min, 30 min, 45 min at 25 0C, 50 0C and 100 0C. The concentration of lead and mercury in Juaro fish lower than the maximum acceptable lever for Pb and Hg respectively (1mg/kg for Pb, 0,5 mg/Kg for Hg). The result indicated that after soaking and boiling in citric acid solution form pineapple extract at concentration 100 % for 45 min at 100 0C reducing heavy metals Pb from 0,02 mg.Kg-1 to 0,003 mg.Kg-1 and Hg from 0,011 mg.Kg-1 to lower than 0,0001 mg.Kg-1. The increasing of soaking time and boiling temperature, the levels of Pb and Hg in Juaro fish Tissue will decreasing
Pillarization of layer double hydroxides (Mg/Al) with keggin type K4[α-SiW12O40]•nH2O and its application as adsorbent of procion red dye
Full text linkPillarization of layered double hydroxides with polyoxometalate K4[α-SiW12O40]•nH2O at various times i.e. 3, 6, 9, 12, 24, 36 and 48 hours has been done. The pillared product was characterized by FT-IR spectrophotometer and XRD. The optimum pillared layered double hydroxides of polyoxometalate K4[α-SiW12O40]•nH2O was used as an adsorbent of procion red dye. The results of characterization using FT-IR spectrophotometer is not yet show the optimum pillarization process. The characterisation using XRD the successfully of pillared layered double hydroxides of polyoxometalate K4[α-SiW12O40]•nH2O showing the existence of diffraction angle 8.5o with intensity 355. Furthermore, the pillared layered double hydroxides of polyoxometalate K4[α-SiW12O40]•nH2O with time variation of 12 hours was applied as an adsorbent of procion red dye. The results show the adsorption rate was 0.523 min-1, the highest of absorption capacity at 70oC was 10.8 mol/g, the highest energy of absorption 70 oC was 125 kJ/mol. The enthalpy (∆H) and entropy (∆S), decrease as the increasing concentration of procion red dye.
Keywords: layered double hydroxides, polyoxometalate, pillaration, procion red, adsorptio
The Diversity of the dragonfly (Odonata) as an indication of water quality
No full textInformation on the diversity of dragonfly in the University area is still not much. Reduced areas that support the growth and development of dragonfly species are thought to have an impact on the decline of the population and the diversity of these species. The purpose of this study identified and analyzed the diversity of dragonfly species. Dragonfly are collected through direct capture and using sticky traps, then visual observations are made for identification. Environmental conditions in the area of Sriwijaya University Campus is still good, with the visibility of environmental parameters in the form of DO, BOD and COD still meet environmental quality standards so that dragonflies are still able to lay eggs to keep their generation. Sriwijaya University campus found 19 species of Odonata belonging to 5 families and 2 sub-ordo, with the value of species diversity index of 2.05 and moderat
Keggin type polyoxometalate H4[αSiW12O40].nH2O as intercalant for hydrotalcite
Full text linkThe 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, Intercalatio