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Hexadecyltrimethylammonium chloride (HDTMA-Cl) has been successfully used to synthesize surfactant-modified zeolite (SMZ) from natural zeolite (NZ). This investigation aims to modify NZ with HDTMA-CL surfactant and investigate its use in the nitrate ion (NO3−) adsorption and desorption, which was carried out using the column method. FTIR, XRD, and SEM-EDX were used to characterize NZ and SMZ. A UV-Vis spectrophotometer was used to analyze the adsorbed and desorbed NO3− concentrations. SMZ has been effectively synthesized with adsorption bands at wavenumbers of 2855 cm−1 and 2924 cm−1 appear in the FTIR result. These bands showed the presence of the amine's symmetrical and asymmetrical CH2 stretch. According to the XRD results, clinoptilolite and mordenite phases predominate in the crystalline structures of NZ and SMZ. The impact of surfactants on NZ also reduces its intensity. A study comparing NZ with SMZ for nitrate adsorption and desorption revealed that SMZ was an effective adsorbent. Furthermore, the results demonstrated that SMZ containing NO3− is still available 24 hours thereafter. [ABSTRACT FROM AUTHOR]

The study aimed to know the effect of size of the activated natural zeolite as a catalyst and sonication time on conversion of cellulose to glucose through hydrothermal method. Natural zeolite was crushed and sieved in the size of 50, 100, and 200 mesh. Zeolite was activated by means of heating at a temperature of 500 °C for 5 hours. The zeolite was characterized using XRD and BET. Hydrothermal conversion of cellulose using variation of zeolite size as a catalyst and sonication time. Product of conversions were measured using the Nelson-Somogyi test. The results showed that the type of natural zeolite is a mordenite. Surface area of activated natural zeolite in the size of 50, 100, and 200 mesh is 13.065, 99.096 and 27.081 m2/g respectively. The highest yield of glucose obtained when it was used an activated natural zeolite in the size of 100 mesh and sonicated as long as 240 minutes with the glucose yield of 12.69 wt%. [ABSTRACT FROM AUTHOR]

Effective and inexpensive adsorbents are needed for wastewater treatment. This study describes the use of Cu/natural zeolite as an adsorbent in the adsorption of remazol black b dye in terms of kinetics and isotherms. Cu/zeolite adsorbent was obtained by activating natural zeolite using HCl and NH4Cl solution then impregnated using Cu(NO3)2.3H2O solution. Characterization of adsorbents using XRD, and SEM-EDX tools. Adsorption with a batch system was carried out at various contact times of 5, 15, 20, 60, and 300 minutes as well as variations in the concentration of 5, 10, 15, 20, 25, and 30 ppm. UV-Vis spectrophotometer was used to measure the concentration of remazol black b dye solution. The adsorption data were tested on the kinetic equations of pseudo-first-order, pseudo-second-order, and intraparticle diffusion. The adsorption isotherms were analyzed using Langmuir, Freundlich, Temkin, Harkin-Jura, Jovanovic, Halsley, Elovich isotherms. The results showed that based on the SEM images, the zeolite after activation was in the form of smaller and more organized granules than the zeolite after activation. XRD analysis showed that the zeolite had a structure of 42.8% mordenite, 39.8% clinoptilolite, and 17% quartz. EDX analysis showed the mass percentage of Cu on the adsorbent was 1.58%. Equilibrium contact time was reached in the 300th minute with an adsorption capacity of 0.4299 mg/g. The largest adsorption capacity was obtained at the initial concentration of remazol black b dye of 25 ppm with an adsorption capacity value of 0.0691 mg/gram. The adsorption of remazol black b dye using Cu/natural zeolite as adsorbent followed pseudo-second-order adsorption kinetics and Langmuir adsorption isotherm pattern. [ABSTRACT FROM AUTHOR]

Bentonite is a popular beauty product, specifically as a face mask. Aside from its wide applications as a skincare product, it is also used to treat diarrhea, allergic contact dermatitis, and an antibacterial agent. Therefore, it is necessary to treat bentonite clay in removing bacteria and fungi without changing its healing or therapeutic properties. In this study, Philippine natural bentonite is characterized using XRD, EDX, and FTIR. Finally, the microbial count was performed to investigate the sterilization capability of γ-irradiation. XRD show that the mineral is primarily composed of mordenite, hectorite, and montmorillonite. EDX analysis reveals that the clay mineral is composed mainly of silica and alumina, which comprises around 86.22% of the total mass. IR transmittance spectra show no significant change in the structure of bentonite upon γ-irradiation except for the higher capacity to hold ambient moisture. Microbial count shows that raw bentonite contains 3.4 x 104 CFU/g. Meanwhile, the bentonite irradiated at 200 and 400 kGy has only <250 CFU/g while the bentonite irradiated at 700 kGy has only <10 CFU/g. The γ-irradiation caused 2-3 log reduction of the microbial content of the Philippine bentonite compared to the untreated bentonite. [ABSTRACT FROM AUTHOR]

Zeolite is minerals contain alumina and silica that cross-linked forming a porous tetrahedron shape. This porous structure is enabling zeolites to have advantage as an adsorbent. One of the common technical application of zeolite is as an adsorbent and one of the ion that have high affinity on zeolites is ammonium. Ammonium is an ion form of ammonia and considered as a waste in environment. The objectives of the research were to characterize and study the ammonium adsorption kinetic and isotherm of the Malang natural zeolites. Characterization of the natural zeolites was conducted by X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy-Energy Dispersive of X-ray Spectroscopy (SEM-EDX) and nitrogen physisorption using Brunaurer, Emmet dan Teller (BET) model. According to the XRD patterns, the natural zeolites were dominated by mordenite and clinoptilolite type of zeolite with quartz as impurity phase. The mordenite phase finding was supported by SEM image that showed the needle shape. Analysis using FTIR showed the peaks correspond to functional groups zeolite framework formation. The SEM-EDX showed that the Si/Al ratio of Malang natural zeolite was 5.5. The surface area calculated by nitrogen physisorption was 52 m2/g. Ammonium adsorption test was conducted by 100 ppm of ammonium solution in the batch reactor with variation on adsorption time and mass loading. Ammonium adsorbed onto the zeolites was increased with the adsorption time and mass loading. The kinetic model of Elovich and isotherm model of Langmuir were best fitted with the ammonium adsorption of Malang natural zeolite. [ABSTRACT FROM AUTHOR]

The metal phase-type is one of the determinants of hydrotreating catalyst activity. Therefore, analysis of the presence of metals and metal oxides phases is an interesting matter to study. In this study, CuMo/mordenite was prepared with various Cu/Mo ratios. The loaded Cu/Mo ratio were 0/4.35; 0.52/4.35; 1.05/4.35; 1.58/4.35; and 2.10/4.35 (wt/wt) namely CuMo/Mor-1, CuMo/Mor-2, CuMo/Mor-3, CuMo/Mor-4 and CuMo/Mor-5, respectively. The analysis results by using Atomic Absorption Spectroscopy indicated that the Cu and Mo metals were successfully impregnated on mordenite. Furthermore, analysis of the metal phase used X-Ray Diffraction, followed by refinement using the Le Bail method with Rietica software. The results of the improved analysis denoted that the metal phases of CuMo/mordenite were Cu (ICSD #43493), Mo (ICSD #41513) and CuMoO4 (ICSD #39439). The morphology of the CuMo/mordenite was observed by the Scanning Electron Microscope completed with EDX (Energy Dispersive X-Ray). The presence of metals did not appear morphologically but detected by EDX. [ABSTRACT FROM AUTHOR]

Biodiesel production from Castor (Ricinus communis) oil was carried out through transesterification using heterogeneous KOH/zeolite catalyst. The aim of this study was to determine the optimum condition of the reaction. The synthesis of the catalyst was initiated through chemical activation of zeolite, followed by the synthesis of KOH/zeolite through ultrasound-assisted method and calcination at 450 oC. Transesterification of castor oil was performed at a temperature of 55, 60 and 65oC; 5, 6, 7 h contact times; and 50, 60, 70% of catalyst concentration. The result of XRD analysis on natural zeolite indicated the zeolite belong the group mordenite. The addition of KOH to the activated zeolite gave rise to new peaks at 2θ: 31, 36, and 38. In addition, the data from XRF analysis indicated there is an increase of potassium (K) amount in KOH/zeolite compared to the activated one. Based on the GC-MS data of biodiesel produced through transesterification, the optimum yield of methyl ricinoleate was achieved at 55 oC, 7 h contact time and 70 % catalyst concentration. A number of physical properties such as water content and density are reported to have not yet met the SNI standard. [ABSTRACT FROM AUTHOR]

Mordenite minerals derived from Sukabumi natural green stone founded in Indonesia was tested in order to remove iron and manganese from natural groundwater. This research used two types of adsorbents which were consisted of physically activated and natural mordenite. Physical activation of the mordenite was carried out by heating at 400-600oC for two hours. Batch system experiments was also conducted as a preliminary experiment. Batch system proved that both activated and natural mordenite minerals were capable of reducing iron and manganese concentration from natural groundwater. Then, continuous experiment was conducted using down-flow system with 45 ml/minute of constant flow rate. The iron & manganese removal efficiency using continuous reactor for physically activated and natural mordenite were 1.38-1.99%/minute & 0.8- 1.49%/minute and 2.26%/minute & 1.37-2.26%/minute respectively. In addition, the regeneration treatment using NH4Cl solution managed to improve the removal efficiency of iron & manganese to 1.98%/minute & 1.77-1.90%/minute and 2.25%/minute & 2.02-2.21%/minute on physically activated mordenite and natural mordenite respectively. Subsequently, the activation of the new mordenite was carried out by immersing mordenite in NH4Cl solution. This chemical activation showed 2.42- 2.75%/minute & 0.96 - 2.67 %/minute and 2.66 - 2.78 %/minute & 1.34 - 2.32 %/minute of iron & manganese removal efficiency per detention time for chemically activated and natural mordenite respectively. [ABSTRACT FROM AUTHOR]

This study aims to investigate the thermal behavior of natural zeolites from Mangatarem, Pangasinan, Philippines. Results obtained from the XRD pattern revealed that the sample is largely composed of mordenite, a Type I zeolite. In the chemical analysis, Si and Al are proven to be the primary components of the sample, which is typical in an aluminosilicate material. It also has a high Si/Al ratio, which suggests that the material is hydrophilic and thermally stable. The TGA analysis showed that dehydration processes dominate the sample's reaction upon heating up to 1000 °C. The initial dehydration process led to a weight loss that is almost equivalent to the moisture content, as measured by chemical analysis. The succeeding weight loss is most probably due to the dehydration of tightly-bound water and cation dehydration. No structural collapse was observed even up to 1000 °C, which suggests that the material is ideal for industrial applications. Lastly, FTIR results revealed that heating the zeolitic tuff led to possible de-alumination. [ABSTRACT FROM AUTHOR]

The aim of present work was to study the influence of SiO2/Al2O3 molar ratio (MR) on nickel behavior in the mordenites with wide variation of MR during reduction in hydrogen flow. It was found that during reduction treatment variation of MR in mordenite from 10 to 206 influences reducibility and mobility of reduced nickel species. Stability of the reduced samples during storage in air at ambient conditions also depends on molar ratio. Variation of MR of mordenite does not change crystal structure, but results in different ionic properties. This effect is explained by variation of acidity of zeolite matrix in line with variation of chemical composition. [ABSTRACT FROM PUBLISHER]

Precession electron diffraction (PED) is a technique which is gaining increasing interest due to its ease of use and reduction of the dynamical scattering problem in electron diffraction, leading to more direct structure solutions. We have performed a systematic study of the effect of precession angle for the mineral andalusite on kinematical extinctions and direct methods solutions where the semiangle was varied from 6.5 to 32 mrad in five discrete steps. We show that the intensities of kinematically forbidden reflections decay exponentially as the precession semiangle (φ) is increased and that the amount of information provided by direct methods increases monotonically but non-systematically as φ increases. We have also investigated the zeolite-framework mineral mordenite with PED and have found a direct methods solution where the 12-ring is clearly resolved for the first time. [ABSTRACT FROM AUTHOR]

A series of Ag+-Cu2+ binary mixtures with different Ag/Cu ratios were supported on mordenite with different Si/Al ratios and were subsequently reduced under hydrogen in the temperature range 323K – 473K. Ag and Cu K-edge X-ray Absorption Spectroscopy (XAS) was conducted on these systems in-situ to monitor the reduction species formed and the kinetics of their reduction. In-situ XANES clearly demonstrates that the formation of silver particles is severely impeded by the addition of copper and that the copper is converted from Cu(II) to Cu(I) during reduction and completely reverts back to Cu(II) during cooling. There are no indications at any stage of the formation of bimetallic Ag-Cu clusters. Interestingly, the Ag/Cu ratio appears to have no influence of the reduction kinetics and reduction products formed with only the highest Si/Al ratio (MR = 128) investigated during this study having an influence on the reduction and stability to air oxidation. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]