Natural Zeolite Clinoptilolite Research Articles

Regulation of sorption processes in natural nanoporous aluminosilicates. 2. Determination of the ratio between active sites

The ratio of acidic and basic sites on natural aluminosilicates (clinoptilolite, nontronite, and glauconite) and their acidic and basic forms were determined based on the catalytic activity of the samples in the reaction of methylbutynol (MBOH) conversion. Conversion of MBOH took place most fully on the natural zeolite (clinoptilolite). The reagent modification of clinoptilolite(treatment with sulfuric acid and alkali) reduced the ratio of acidic and basic sites. Conversion of MBOH on clay minerals increased in the acid-modified samples and decreased upon the alkali treatment, which corresponds to the change in the ratio of acidic and basic sites in both nontronite and glauconite, but to a greater extent in spherulite-like clay mineral glauconite.

ADSORBENT FROM WASTE AND NATURAL DEPOSITS FOR PARAQUAT REMOVAL IN WATER

Studies on the removal of frequently used herbicide for controlling broad-leafed weeds, Paraquat Dichloride (PQ) has been carried out intensively. Waste from steelmaking industries (Electric Arc Furnace (EAF) slag) and natural zeolite (clinoptilolite) were used as the starting materials. Preparation of an adsorbent involved two steps, namely extraction iron oxide (IO) from slag and precipitation of IO onto clinoptilolite. Characterization of NZIC were done using Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), single-point Brunauer Emmett Teller (BET) surface area analysis, Vibrating Sample Magnetometer (VSM) and pH at zero point charge (pHzpc). The NZIC showed a lower magnetic saturation at 8.13 emu/g compared to maghemite at 29.5 emu/g. The BET surface area of NZIC was 146.29 m2/g, larger compared to the individual surface area of clinoptilolite and maghemite which are 37.84 and 17.84 m2/g respectively. Adsorption of PQ onto clinoptilolite and NZIC were investigated using a batch experiment. Surface characteristic of NZIC was investigated by pHzpc experiment showing that at pH 8.2 its electric surface charge is zero. Optimum parameters for adsorption of PQ in water were found at pH 12 with 0.01 g/10 mL of NZIC and equilibrium time of 20 minutes. Desorption experiment revealed that NZIC have a good recovery in repetitive usage for PQ removal in water.

CLINOPTILOLITE TUFF AND OTHER ZEOLITE ADDED VALUE PRODUCTS AS SUSTAINED COMMODITIES IN TRADITIONAL WATER AND WASTE MANAGEMENT

Coagulation/flocculation and ion exchange onto natural zeolite clinoptilolite are reviewed and discussed in this paper based on their pilot or industrial applications. Surface water purification by means of chemical coagulation and flocculation supported by the powdered natural zeolite was carried out industrially to save drinking water reservoir (upper part of Ondava river) settled by about ten thousands inhabitants. Therefore, several other surface water samples from the Slovakian reservoirs potentially impacted by contamination were examined to treat with alum coagulation/flocculation and powdered clinoptilolite tuff addition at the laboratory, respectively. Ammonia removal from tannery wastewater using the clinoptilolite tuff with chemical regeneration and regenerant recovery by air stripping, carried out in pilot measure during the several months at the mixed Wastewater Treatment Facility in Otrokovice - WTFO is discussed and evaluated, respectively.

Competitive Removal of Malachite Green and Rhodamine B Using Clinoptilolite in a Two-dye System

AbstractSurface and groundwaters become contaminated with dyes due to discharge into the environment, which increases the risk of a number of human diseases. Many methods of dye removal from discharge waters at the source have been developed, but few are effective and the most effective method (activated carbon) is very expensive. The purpose of the present study was to test a natural zeolite (clinoptilolite type) as a potentially effective and inexpensive method to remediate dye discharge into the environment. In the removal experiments, malachite green (MG) and rhodamine B (RB) cationic dyes were used. The effects of various experimental conditions such as initial dye concentration, pH, and temperature on dye removal were investigated in a single-dye system. The degree of removal of MG and RB increased with increasing initial concentration and temperature of the dye in a single-dye system. An increase in pH decreased RB removal, but increased MG removal. In a two-dye system, MG and RB adsorption decreased by ~41.74 and 21.51%, respectively, due to competitive adsorption of the two dyes. Adsorption reflected a pseudo-second order kinetics model with high correlation coefficients (r2 = 0.996–1.000) in single-dye and two-dye systems. Adsorption was most consistent with the Langmuir-1 and the Redlich-Peterson isotherm models with high correlation coefficients (r2 = 0.987–0.999) in both systems. The Langmuir-1 adsorption capacities were determined as 43.86 and 44.25 mg/g for the removal of MG and RB in single-dye systems, respectively. In a two-dye system, the Langmuir-1 capacities were 20.62 and 31.54 mg/g for the removal of MG and RB, respectively.

Research into the properties of concrete modified with natural zeolite addition

Concrete mixture used for the tests consisted of cement CEM I 42.5 R, natural zeolite (clinoptilolite), 0/4 fr. sand as fine aggregate, and 4/16 fr. gravel as coarse aggregate. Active components of the zeolite were determined by means of X-ray diffraction analysis, particle form (plate-shaped) and size (11.82μm) were determined by means of SEM. 5 batches of specimens were made with zeolite content ranging from 0 to 10% (the binding material was substituted with natural zeolite). The following parameters of modified concrete were tested: compressive strength, water absorption, density, ultrasonic pulse velocity, porosity (open and closed), predicted freeze-thaw resistance. Substitution of up to 10% of cement with natural zeolite increases the compressive strength of concrete by 15%, reduces water absorption 2.3 times, increases density and ultrasonic pulse velocity. Substitution of up to 10% of cement with natural zeolite increases closed porosity and subsequently improved the freeze-thaw resistance of concrete. The predicted freeze-thaw resistance calculations revealed 3.3 times higher resistance of concrete modified with up to 10% of natural zeolite.

X-ray photoelectron spectroscopic investigation into the surface effects of sulphuric acid treated natural zeolite

Natural zeolite is considered to be an effective and economical crystalline aluminosilicate adsorbent and catalyst. In the treatment of coal seam gas (CSG) co-produced water, it has the potential to become an economic alternative filtration medium for the reduction of excessive Na content. A variety of methods for the modification of natural zeolite have been used to improve its surface properties. This study reports the results of X-ray photoelectron spectroscopy (XPS) analysis on the near-surface of natural zeolite (clinoptilolite and quartz) particles before and after modification by sulphuric acid. The atomic % and binding energies of the chemical elements comprising zeolite are changed significantly following acid treatment. With increasing sulphuric acid concentration, the Si/Al atomic ratio increases from 2.99 at 0M to 4.92 at 5M. The binding energy (BE) shifts show a similar trend with increasing acid concentration. High-resolution and valence band spectra show that the BE shifts are influenced by cation removal from the zeolite structure. These detailed XPS results are useful for understanding changes in the sodium adsorption capacity of zeolite by acid modification to enhance its suitability for use in treatment of CSG co-produced water.

Natural zeolites in diet or litter of broilers

This study aims to analyse the influence of adding natural zeolites (clinoptilolite) to the diet or litter of broilers and their effects on growth performance, carcass yield and litter quality.Three consecutive flocks of broilers were raised on the same sawdust litter, from d 1 to d 42 of age, and distributed in three treatments (control with no added zeolites, addition of 5 g/kg zeolite to diet and addition of 100 g/kg zeolites to litter).The addition of zeolites to the diet or litter did not affect growth performance or carcass yield.The addition of zeolites to the diet did not influence moisture content of the litter, ammonia volatilisation was reduced only in the first flock and pH of litter was reduced in the second and third flock.However, the addition of zeolites to the litter reduced moisture content, litter pH and ammonia volatilisation in all flocks analysed.The addition of 5 g/kg zeolite to the diet in three consecutive flocks was not effective in maintaining litter quality, whereas the addition of 100 g/kg natural zeolites to sawdust litter reduced litter moisture and ammonia volatilisation in three consecutive flocks raised on the same litter.

Recovery of nitrogen from high strength waste stream by using natural zeolite (Clinoptilolite)

【This paper presents the applicability of natural zeolite (Clinoptilolite) for recovery of ammonium nitrogen from high-strength wastewater stream. Isotherm experiments showed the ammonium exchange Clinoptilolite followed Freundlich isotherm and its maximum exchange capacity was $18.13mg\;NH_4{^+}-N/g$ zeolite. The X-ray photoelectron spectroscopy (XPS) analysis indicated that a significant amount of nitrogen was adsorbed to the Clinoptilolite. Optimal flowrate for recovery of high concentration ammonium nitrogen was determined at 16 BV/d (=19.2 L/min) throughout the lab-scale column studies operated under various flowrate conditions. This study also provided a method to determine the recovery rate of final product of nitrogen fertilizer based on the model application to the lab-scale continuous data.】

Nitrogen and phosphorous adsorption from post-hydrothermal liquefaction wastewater using three types of zeolites

Hydrothermal liquefaction (HTL) has been studied as a promising technology for converting wet biomass into bio-crude oil and the nutrient-rich post-hydrothermal liquefaction wastewater (PHWW) could be reused for algae and bacteria production. However, the PHWW from HTL contains various types of contaminants that need to be removed before reuse. Too high nutrients (nitrogen and phosphorous) contents, such as ammonium, are inhibitive to algal growth and bacteria species in anaerobic process. It is desirable to reduce nutrients concentration in PHWW to an acceptable level using zeolite adsorption. This study investigated nitrogen and phosphorous adsorption efficiencies from PHWW using three types of zeolites: activated clinoptilolite, natural clinoptilolite and Na-modified zeolite. Effects of ions and pH in the adsorption process were also investigated. Results showed that three zeolite variables affecting ammonium adsorption process could be ranked as follows: zeolite dosage > type > particle size, via an orthogonal experiment design. Activated clinoptilolite, with a particle size of 0.18-0.30 mm and a dosage of 0.4 g/mL demonstrated the highest ammonium adsorption efficiency of 54.92%. Zeolite could also adsorb organic nitrogen and had a high adsorption efficiency of phosphorous (97.85%). This study showed that zeolite is effective to adsorb nutrients in PHWW. The adsorption treated PHWW can then be used for culturing algae or anaerobic treatment, and the adsorbed nutrients can be reused later. Keywords: adsorption, ammonium, nutrients; phosphorous, zeolite, post-hydrothermal liquefaction wastewater (PHWW) DOI: 10.3965/j.ijabe.20150805.1561 Citation: Ran X, Duan N, Zhang Y H, Li B M, Liu Z D, Lu H F. Nitrogen and phosphorous adsorption from post-hydrothermal liquefaction wastewater using three types of zeolites. Int J Agric & Biol Eng, 2015; 8(5): 86－95.

Spectroscopic study and catalytic activity for H2O2 decomposition of new zeolite-porphyrin systems

In this paper, some new catalytic systems—a metallic complex of 5,10,15,20-tetra-p-tolyl-porphyrin (TTP) with Fe [ClFe(III)TTP] entrapped into a natural zeolite (clinoptilolite) and into two synthetic zeolites (X-71, HZSM-5) were synthesized and characterized by energy-dispersive X-ray fluorescence (EDXRF), Fourier transform infrared spectroscopy (FTIR), UV–Vis spectroscopy, thermal analyses (TGA/SDTA) and tested subsequently as catalysts in the hydrogen peroxide decomposition reaction. The metalloporphyrin ClFe(III)TTP used was adsorbed in different proportions on the zeolite matrix. It is entrapped into The X-71 zeolite (due to its higher pore size), and adsorbed onto the other zeolites: HZSM-5 and clinoptilolite. The catalytic activities of the synthesized systems were discussed from kinetic and mechanistic aspects points of view. This paper also evidenced the generation of oxo-dimers of porphyrin during the catalytic reaction, this aspect being valuable for ClFe(III)TTP. The study of the catalytic activities of the synthesized systems leads us to the proposal of an adequate mechanism for the degradation of hydrogen peroxide in the presence of the synthesized catalysts. The most efficient catalyst according to our study is the ClFe(III)TTP/X-71 system.

Removal of Ag(I) from Aqueous Solution by Japanese Natural Clinoptilolite

The present study examined the adsorption of silver ion in aqueous solution onto natural clinoptilolite zeolite from Futatsui Mine, Akita Prefecture, Japan. The effects of various parameters, i.e., solution pH, adsorbent dosage, adsorption time, silver ion solution concentration, and temperature, on silver ion adsorption process onto clinoptilolite were examined. Additionally, the thermodynamics of the silver ion adsorption process was investigated. The optimum pH for silver adsorption was determined to be around 4.0. The adsorption process could be well described by the Langmuir isotherm model. The calculated maximum adsorption capacity was 0.64 mmol/g. Adsorption kinetics studies were also conducted. The results showed that the adsorption process preferentially followed the pseudo-second-order kinetics model over the pseudo-first-order model. Furthermore, with decreasing aqueous solution temperatures, the adsorption kinetics became slower and the amount of silver ion adsorbed increased. The thermodynamic values, ΔG0, ΔH0, and ΔS0, indicated that adsorption was an exo-thermic and spontaneous process.

Effect of natural zeolite (clinoptilolite) on ammonia emissions of leftover food-rice hulls composting at the initial stage of the thermophilic process

Effect of natural zeolite (clinoptilolite) on ammonia emissions of leftover food-rice hulls composting at the initial stage of the thermophilic process

A density functional theory study of arsenic immobilization by the Al(III)-modified zeolite clinoptilolite.

We present density functional theory calculations of the adsorption of arsenic acid (AsO(OH)3) and arsenous acid (As(OH)3) on the Al(III)-modified natural zeolite clinoptilolite under anhydrous and hydrated conditions. From our calculated adsorption energies, we show that adsorption of both arsenic species is favorable (associative and exothermic) under anhydrous conditions. When the zeolite is hydrated, adsorption is less favourable, with the water molecules causing dissociation of the arsenic complexes, although exothermic adsorption is still observed for some sites. The strength of interaction of the arsenic complexes is shown to depend sensitively on the Si/Al ratio in the Al(III)-modified clinoptilolite, which decreases as the Si/Al ratio increases. The calculated large adsorption energies indicate the potential of Al(iii)-modified clinoptilolite for arsenic immobilization.

Simultaneous separation-preconcentration and determination of trace amounts of mercury and cadmium in fruits, vegetables and biological samples

A method for the simultaneous preconcentration and determination of Hg(II) and Cd(II) at the ng/mL level was studied. This method is based on solid phase extraction using 2-nitroso-1-naphthol-4-sulfonic acid modified natural clinoptilolite zeolite that is selective for mercury and cadmium. The adsorbed complexes could be eluted using dimethylformamid and the concentration of mercury and cadmium were determined by derivative spectrophotometry at appropriate (dA/dλ)s in order to work on the basis of H-point standard addition method. In optimum conditions, detection limit in the original solution is obtained 0.1 ng/mL for mercury and 0.8 ng/mL for cadmium. The preconcentration factor attainable for quantitative recovery (>95%) of Hg(II) and Cd(II) were 95 and 105 for a 1000 mL sample volume, respectively. Five times replicating determination a mixture of mercury and cadmium in 5.0 mL final solution gave a relative standard deviation of 7.8% for Hg(II) and 6.5% for Cd(II). The proposed method is applied to determine mercury and cadmium ions in plant and biological samples successfully.

Оценка потребительских рисков при изготовлении малотоксичной фанеры

Currently, the use of wood plate materials (WPM) in various industries is steadily increasing due to a number of technological and economic advantages. Along with this, there is the improvement of methods of manufacturing and materials used for this purpose. One of the most commonly types of glue used for production of plywood as one of the types of WPM are urea-formaldehyde resins. In the manufacture of adhesive compositions based on them possible to use a wide range of sorbents that provide a variety of improved technological properties, such as adhesive, and the finished plywood. One of these properties is the level of free formaldehyde emissions from finished plywood, which directly affects to the possibility of its using in different rooms and characterizes the level of consumer risks in its operation. Scientifically it proved possible to reduce the level of emission of free formaldehyde from finished plywood with using of natural zeolite clinoptilolite treated in weak pulsed magnetic fields (SIMP) and ultra-high frequency electromagnetic fields (EMF microwave), as a sorbent of urea-formaldehyde resin filler in the manufacture of plywood for general using. This study evaluated the level of consumer risks in the operation of plywood manufactured with sorbent activated in SIMP and microwave EMF. In this paper describes the main influencing factors as well as the possibility of reducing calculation errors in consumer risk shows the feasibility of using a simplified calculation of constant values while respecting the basic influencing factors. Calculations of changes in con-sumer risk for saples of plywood manufactured with using sorbents, activated in SIMP and EMF microwave were made, established decrease by 25 and 33 % respectively.

Leaching and antimicrobial properties of silver nanoparticles loaded onto natural zeolite clinoptilolite by ion exchange and wet impregnation

ABSTRACTThis study aimed to compare the leaching and antimicrobial properties of silver that was loaded onto the natural zeolite clinoptilolite by ion exchange and wet impregnation. Silver ions were reduced using sodium borohydride (NaBH4). The leaching of silver from the prepared silver-clinoptilolite (Ag-EHC) nanocomposite samples and their antimicrobial activity on Escherichia coli Epi 300 were investigated. It was observed that the percentage of silver loaded onto EHC depended on the loading procedure and the concentration of silver precursor used. Up to 87% of silver was loaded onto EHC by wet impregnation. The size of synthesized silver nanoparticles varied between 8.71–72.67 nm and 7.93–73.91 nm when silver was loaded by ion exchange and wet impregnation, respectively. The antimicrobial activity of the prepared nanocomposite samples was related to the concentration of silver precursor used, the leaching rate and the size of silver nanoparticles obtained after reduction. However, only in the case of the nanocomposite sample (Ag-WEHC) obtained after loading 43.80 ± 1.90 µg of Ag per gram zeolite through wet impregnation was the leaching rate lower than 0.1 mg L−1 limit recommended by WHO, with an acceptable microbial killing effect.

The effect of acid treatment on the reactivity of natural zeolites used as supplementary cementitious materials

This work investigated the use of acid treatment as a method for increasing the reactivity of natural zeolite used as a supplementary cementitious material. The effects of treating a natural clinoptilolite zeolite with nine acid solutions, 0.1M, 0.5M, or 1M hydrochloric or nitric acid or 0.1M, 0.5M, or 0.87M acetic acid, were measured using x-ray diffraction, particle size analysis, pore size distribution and surface area analysis. The zeolite pozzolanic reactivity was determined by measuring the quantity of portlandite in hydrated zeolite-cement paste after 28 and 90days. Results showed that acid treatment increased zeolite surface area, resulting in increased zeolite pozzolanic reactivity, independent of the solution concentration used. Cement hydration was also increased, evidenced by greater rates of heat evolution from cement-zeolite pastes. Additionally, although reductions of portlandite occurred most quickly in pastes with zeolites treated with strong acids, by 90days the zeolites treated with acetic acid solutions showed comparable portlandite reductions.

Cement hydration with ultrasound treated clinoptilolite

There are many cement replacement materials and one of them is zeolites. Zeolites are crystalline solids structures made of silicon, aluminum and oxygen that form a framework with cavities and channels inside where cations, water and/or small molecules may reside. In this study natural zeolite clinoptilolite was used. Clinoptilolite is the most popular natural zeolite mineral with the chemical formula (Na, K, Ca)23Al3(Al,Si)2Si13O3612H2O. The present paper shows the results of using ultrasound treated clinoptilolite as Portland cement replacement material. The duration of ultrasound treatment was 5 min, 10 min, and 20 min. Results showed that the XRD of ultrasound-treated clinoptilolite slightly differs in comparison to conventional clinoptilolite. The cement samples with 5% and 10% clinoptilolite substitute provide the strength increase, 30% significantly reduces the strength compared to control samples. The heat measurements of Portland cement paste hydration, containing clinoptilolite, showed that the clinoptilolite slightly increases the duration of hydration, but hydration temperature is lower than in the controls samples. The experimental results suggest that ultrasound-treated clinoptilolite positively influence cement hydration processes, consolidation kinetics, CSH formation; the mechanical strength of the samples is increased. Typical content of Portland cement substituting does not exceed 20% of mass of Portland cement in samples. Reducing the consumption of Portland cement with substituting it with ultrasound treated clinoptilolite is preferred for reasons of environmental protection.DOI: http://dx.doi.org/10.5755/j01.sace.11.2.12430

Studies of Reversible Hydrogen Binding in Nano- Sized Materials

Experimental review of materials suitable for reversible hydrogen binding in nanoporous and nanosized structures of materials, based on natural zeolite (clinoptilolite) and graphene (exfoliated electrochemically from raw graphite), were analyzed. Characterization of materials with SEM, XRD, EDS and Raman spectroscopy methods and aspects of synthesis of a nanostructured zeolite and a few-layer graphite material was done in this work. It was established from gas analyzer results that hydrogen mass fraction in natural zeolite ranged from 1.1 % to 1.4 %, but in the few-layer graphite material − from 0.39 % to 0.46 %.

Characterization of natural zeolite clinoptilolite for sorption of contaminants

The nanoparticles technology has received considerable attention for its potential applications in groundwater treatment for the removal of various pollutants as Cadmium. In this work, iron boride nanoparticles were synthesized in pure form and in presence of homo-ionized zeolite clinoptilolite, as support material. These materials were used for removing Cd (II) from aqueous solutions containing 10, 50, 100, 150, 200, 250, 300 and 400 mg/L. The characterization of these materials was made by using X-ray Diffraction, Scanning Electron Microscopy and Mossbauer Spectroscopy. Pure iron boride particles show a broad X-ray diffraction peak centered at 45∘ (2𝜃), inferring the presence of nanocrystals of Fe2B as identified from Mossbauer Spectroscopy. The size of these Fe2B particles was within the range of 50 and 120 nm. The maximum sorption capacities for Cd (II) of iron boride particles and supported iron boride particles in homo-ionized zeolitic material were nearly 100 %. For homo-ionized zeolite and homo-ionized zeolite plus sodium borohydride was ≥ 95 %.