scholarly journals Species sensitivity of zeolite minerals for uptake of mercury solutes

2006 ◽  
Vol 70 (4) ◽  
pp. 361-371 ◽  
Author(s):  
L. S. Campbell ◽  
A. Chimedtsogzol ◽  
A. Dyer
Keyword(s):  
Mercury Concentration ◽  
Natural Zeolite ◽  
Natural Zeolites ◽  
Species Sensitivity ◽  
Voltammetric Study ◽  
Mercuric Nitrate ◽  
Different Types ◽  
Positive Correlations ◽  
Solute Species ◽  
Nitrate Solutions

AbstractThe uptake of inorganic Hg2+ and organometallic CH3Hg+ from aqueous solutions by 11 different natural zeolites has been investigated using a batch distribution coefficient (Kd) method and supported by a preliminary voltammetric study. The effect of mercury concentration on the Kd response is shown over an environmentally appropriate concentration range of 0.1–5 ppm inorganic and organometallic Hg using a batch factor of 100 ml g-1 and 20 h equilibration. Analcime and a Na-chabazite displayed the greatest methylmercury uptakes (Kd values at 1.5 ppm of 4023 and 3456, respectively), with mordenite as the smallest at 578. All uptake responses were greater for methylmercury than for the inorganic mercuric nitrate solutions, suggesting a distinctive sensitivity of zeolites to reaction with different types of solute species. It is likely that this sensitivity is attributable to the precise nature of the resultant Hg-zeolite bonds. Additionally, both the Si-Al ratio and the Na content of the initial natural zeolite samples are shown to influence the Kd responses, with positive correlations between Kd and Na content for all zeolites excluding mordenite.

Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites

Clay Minerals ◽  
2011 ◽  
Vol 46 (2) ◽  
pp. 241-250 ◽  
Author(s):  
V. Lilkov ◽  
O. Petrov ◽  
V. Petkova ◽  
N. Petrova ◽  
Y. Tzvetanova
Keyword(s):  
Surface Area ◽  
Cement Paste ◽  
Chemical Reactions ◽  
Natural Zeolite ◽  
Early Stage ◽  
Pozzolanic Activity ◽  
Large Surface Area ◽  
Natural Zeolites ◽  
Hydration Products ◽  
Cement Pastes

AbstractThis paper presents results from comparative thermogravimetric, calorimetric and pozzolanic activity analyses of five natural zeolite samples from Bulgaria, Slovakia, Philippines, USA and North Korea. The zeolites actively participate in the hydration processes of cement. Their activity in the early stage of hydration is based mainly on the large surface area of the particles while, in the later stages of activation, chemical reactions occur between the products of the hydration of cement and the soluble SiO2 that is present in the bulk of the zeolites. It has been shown that in all cement pastes which contain zeolite additives, the quantity of portlandite is lower than that in pure cement paste or is even totally absent. The amounts of hydration products are greater when 30% zeolite is used than when 10% zeolite is added (excluding the sample with chabazite). The lowest pozzolanic activity is shown by chabazite, which possessed the lowest SiO2/Al2O2 ratio.

scholarly journals REDUCTION OF METAL CATIONS CONTENT FROM THE AQUEOUS SOLUTIONS BY SORBENTS

2021 ◽  
Vol 2021 (6) ◽  
pp. 5307-5311
Author(s):  
IVETA PANDOVA ◽  
◽  
MIROSLAV RIMAR ◽  
Keyword(s):  
Heavy Metals ◽  
Aqueous Solutions ◽  
Natural Zeolite ◽  
Metal Cations ◽  
Sorption Kinetics ◽  
Synthetic Zeolite ◽  
Natural Zeolites ◽  
Chemically Treated ◽  
Synthetic Zeolites

The article presents the results of research on reducing the concentration of heavy metals, such as copper and nickel, on natural zeolite in comparison with synthetic zeolite and chemically treated natural zeolite. The reduction of the content of specific types of heavy metals from aqueous solutions was investigated by the method of sorption kinetics. The results indicate the ability of natural zeolites to compete with synthetic zeolites.

scholarly journals Pengujian Zeolit Alam Mordenit Sebagai Penjerap Proses Pendegradasian Kandungan Amonium di dalam Air Tambak

2020 ◽  
Vol 21 (1) ◽  
pp. 49-55
Author(s):  
Nuryoto Nuryoto ◽  
Teguh Kurniawan ◽  
Indar Kustiningsih
Keyword(s):  
Particle Size ◽  
Natural Zeolite ◽  
The Other ◽  
Ammonium Concentration ◽  
Small Fish ◽  
Natural Zeolites ◽  
Absorption Time ◽  
Adsorption Time ◽  
Research Results ◽  
Other Hand

ABSTRACTIndonesia has an abundant quantity of natural zeolites that have not yet been utilized maximally. On the other hand, fishpond farmers have a problem regarding the presence of ammonium in the fishpond water which will negatively impact to survival of fish, especially small fish. To solve this problem, this research was utilizing natural zeolite to degrade ammonium in the fishpond water. This research aimed to test mordenite natural zeolite from Bayah as an adsorbent to collaborate some variables impact to reach more maximal adsorption. The variables that were used to be observed were: mordenite natural zeolite from Bayah as an adsorbent which has been activated by 1-7 N H2SO4 and the other was without activation, ammonium concentration of 80-800 ppm, the particle size of adsorbent of 80 and 150 mesh, stirring speed of 600 and 800 rpm, and without stirring by duration adsorption time of 60 minutes. The research results showed that mordenite natural zeolite after activated was able to adsorb of 100% ammonium, while for the mordenite natural zeolite from Bayah without stirring was of 80%, by the same absorption time. These results will give significant benefits for fishpond farmers to increase their productivity because of the increase in fish survival.Keywords: adsorption, adsorbent, zeolite, amoniumABSTRAKKandungan zeolit alam di Indonesia cukup melimpah dan belum termanfaatkan secara maksimal. Pada sisi lain petani tambak dihadapkan pada masalah terdapatnya kandungan amonium di dalam air tambak, yang akan berdampak negatif bagi keberlangsungan hidup ikan, terutama ikan yang masih kecil. Penelitian ini mencoba memanfaatkan zeolit alam guna mendegradasi kandungan amonium dalam air tambak. Tujuan penelitian ini adalah melakukan pengujian terhadap zeolit alam mordenit dari Bayah sebagai adsorben, baik dilakukan dengan pengadukan maupun tanpa pengadukan, serta mengkolaborasi beberapa variabel yang berpengaruh agar hasil adsorpsi lebih maksimal. Observasi dilakukan dengan zeolit alam mordenit dari Bayah yang telah diaktivasi dengan 1-7 N H2SO4 maupun tanpa aktivasi, rentang konsentrasi larutan amonium 80-800 ppm, ukuran partikel adsorben 80 dan 150 mesh, kecepatan pengadukan 600 dan 800 rpm, dan tanpa pengadukan serta lamanya waktu penyerapan 60 menit. Hasil penelitian menunjukan hasil yang sangat baik, dan secara umum zeolit alam mordenit Bayah teraktivasi telah mampu melakukan adsorpsi amonium sebesar 100%, sedangkan untuk zeolit alam mordenit Bayah tanpa pengadukan sebesar 80% pada waktu adsorpsi yang sama.Kata kunci: adsorpsi, adsorben, zeolit, amonium

Influence of Zeolites On The Degradation of Arabian Light Crude Oil

1999 ◽  
Vol 1999 (1) ◽  
pp. 1059-1063
Author(s):  
J. R. Bergueiro ◽  
A. Pita ◽  
M. A. Mayol ◽  
M. Rallo ◽  
J. López-Ruiz
Keyword(s):  
Gas Chromatography ◽  
Crude Oil ◽  
Time Evolution ◽  
Marine Bacteria ◽  
Natural Zeolite ◽  
Sea Water ◽  
Time Intervals ◽  
Light Crude Oil ◽  
Different Types ◽  
Similar Sample

ABSTRACT The authors have studied the biodegradation of an Arabian Light crude oil in sterile marine water by the CUES229 marine bacteria and the BIOLEN IG30 biologic activator, both in the presence and the absence of zeolites. Two different types of zeolites, a natural one (NZ) and an artificial one (Zestek56), were used to degrade the crude in the first experiment, arising a 20% increment in the degradation in the presence of natural zeolite when compared with a similar sample without zeolites, and a 9% in the artificial zeolite. Next set of experiment were made using reactors filled with 250 g of sea water and 0.02 g of zeolite and injecting CUES 229 bacteria up to 108 cells/ml. Samples were introduced in a shaker at 110 rpm and with regulated temperature at 30-C. Time evolution of the biodegradation was deduced from gas chromatography at the time intervals 1; 7 and 15 days. Later, a similar experiment, but with BIOLEN IG30, was also made. Biodegradation of aliphatic hydrocarbons was observed –after 15 days- until the C14 fractions, using zeolites plus Biolen IG30, and until the C18 fractions, using zeolite plus CUES 229 bacteria.

scholarly journals Utilization of Natural Zeolites as Cu (Ii) and Zn (Ii) Adsorbent

2017 ◽  
Vol 21 (3) ◽  
pp. 153
Author(s):  
Evi Mutiara Dewi ◽  
. Suwardi ◽  
Dyah Tjahyandari Suryaningtyas ◽  
Syaiful Anwar
Keyword(s):  
Natural Zeolite ◽  
Data Interpretation ◽  
Exchange Capacity ◽  
Natural Zeolites ◽  
Saturation Point ◽  
Isothermal Adsorption ◽  
Zn Content ◽  
System Data ◽  
Physical And Chemical ◽  
Adsorption Capability

This research was aimed to determine the differences of physical and chemical characteristics from three natural zeolites from Tasikmalaya, Bayah and Lampung areas and to examine the characteristics of the natural zeolite adsorption capability to the micro-nutrients. The zeolite characterization analysis included some variables i.e. mineral types, morphologyand pH, CEC (Cation Exchange Capacity), BSP (Base Saturation Point), Cu and Zn content of zeolite.  Analysis of natural zeolite adsorption characteristics were done by Batch System. Data interpretation were done by  using the isothermal adsorption equation of Langmuir, Freundlich and Brunauer-Emmett-Teller (BET).The results showed that zeolite from Bayah and Tasikmalaya had a similiar morphology and it was categorized as mordenite types and platy structure, while zeolite from Lampung was a clinoptilolite type and tabular structure. The CEC of Tasikmalaya zeolite (137.58 cmol(-)kg-1) was higher than Bayah (96.75 cmol(-)kg-1) and Lampung (87.72 cmol(-)kg-1). Adsorption capability at the Langmuir equation of Cu by Bayah zeolite (47.619 mg g-1) was higher than Lampung (33.333 mgg-1) and Tasikmalaya (28.571 mg g-1). Effective adsorption of Zn by Bayah zeolite 19.417 mg g-1 was higher than  Lampung (16.949 mg g-1) and Tasikmalaya (1.395 mg g-1).

scholarly journals PEMANFAATAN ZEOLIT ALAM SEBAGAI MEDIA PENDUKUNG AMOBILISASI ENZIM α-AMILASE

2015 ◽  
Vol 5 (1) ◽  
pp. 79
Author(s):  
Upita Septiani ◽  
Agrina Lisma
Keyword(s):  
Surface Morphology ◽  
Unit Activity ◽  
Incubation Time ◽  
Natural Zeolite ◽  
Immobilized Enzyme ◽  
Natural Zeolites ◽  
Optimum Temperature ◽  
Optimal Activity ◽  
Immobilization Enzyme ◽  
The Stability

 ABSTRACT The utilization of natural zeolite as supporting media of α-amylase enzyme has been done. Natural zeolite which is activated with 3M HCl can remove impurities in the surface natural zeolite, uncover and widen the pores of the zeolite and activate functional groups to interact with α-amylase enzyme in the process of immobilization enzyme process. The mass of activated natural zeolite which is used as a material immobilized to get the optimal activity of α-amylase enzyme was 0.3 gram. Based on the measurement result of optimization of α-amylase enzyme were obtained optimum temperature of 35 oC, pH 5.6 and incubation time of 35 minutes with 0.04845 units/mL of the unit activity. And for α-amylase immobilized enzyme will be stable at the optimum temperature of 50 oC, pH 5.6 and incubation time of 45 minutes with 0.030 units/mL of the unit activity. SEM-EDX pattern shows the differences in surface morphology between natural zeolite and activated natural zeolites which contain α-amylase enzyme. A mobilization technique can increase the stability utilized in a α-amylase enzyme. Keywords : Zeolite, amobilization, α-amylase enzyme

scholarly journals Adsorpsi Asam Humat pada Zeolit Alam yang Dimodifikasi dengan TiO2

2020 ◽  
Vol 11 (1) ◽  
pp. 43-51
Author(s):  
Upita Septiani ◽  
Fiska Julian Tasari ◽  
Zilfa Zilfa
Keyword(s):  
Humic Acid ◽  
Adsorption Capacity ◽  
Natural Zeolite ◽  
Sol Gel ◽  
Sem Analysis ◽  
Maximum Adsorption Capacity ◽  
Natural Zeolites ◽  
X Ray ◽  
West Sumatra ◽  
Silica Alumina

This research modified natural zeolite with TiO2 synthesized by the sol-gel process which was applied as a humic acid adsorbent. The purpose of this study was to coat natural zeolites with TiO2 to increase the adsorption capacity of natural zeolites as humic acid adsorbents. The natural zeolite powders were obtained from Kabupaten Solok, West Sumatra, based on X-ray Fluorescence (XRF) analysis, the ratio of silica/alumina (Si/Al) was 4.35, indicating that natural zeolite was clinoptilolite zeolite. Scanning Electron Microscopy (SEM) analysis showed natural zeolite has a rough surface with closed pores while zeolite coated with TiO2 (zeolite/TiO2) has a homogeneous, smooth surface with open pore. The results of the Energy Dispersive X-Ray Spectroscopy (EDS) analysis showed that the level of TiO2 was 7.1%, this result showed that TiO2 has been coated on the surface of the zeolite. Natural zeolite and zeolite/TiO2 were applied as humic acid adsorbents. Maximum adsorption capacity of natural zeolites and zeolites/TiO2 were 0.2787 mg/g and 1.199 mg/g, respectively.

scholarly journals Propiedades Básicas de Zeolitas Naturales de Panamá con Potencial de Desarrollo Industrial

2018 ◽  
Vol 3 (1) ◽  
pp. 721
Author(s):  
Dr. Cecilio Hernández B. ◽  
M.Sc. Jorge Olmos ◽  
Licda. Yahaira Espinosa
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Volcanic Activity ◽  
Natural Zeolite ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Natural Zeolites ◽  
Low Levels ◽  
Initial Results

The initial results of the properties that have been determined to a sample of natural zeolite, coming from areas of volcanic activity of Panama, and that has been identified with potential for its industrial explotation, are presented. Some physicochemical properties, chemical composition and morphology were determined. A natural zeolite with an intermediate level of Si/Al (2.62), low levels of dissolved salts and a morphology with pores-shaped channels with a diameter of 5 mm are observed.Keywords: natural zeolites, chemisorption, morphology, macropores, cation exchange capacity

Ion exchange with natural zeolites: an alternative for water softening?

2005 ◽  
Vol 51 (11) ◽  
pp. 71-77 ◽  
Author(s):  
S. Cinar ◽  
B. Beler-Baykal
Keyword(s):  
Ion Exchange ◽  
Natural Zeolite ◽  
Quantitative Data ◽  
Natural Zeolites ◽  
Water Softening ◽  
Promising Alternative ◽  
Low Concentrations ◽  
Calcium Removal

Possibility of using natural zeolites for water softening was investigated. Quantitative data regarding separation of calcium from water at various levels of hardness through ion exchange with the ammonium selective natural zeolite clinoptilolite is reported. Capacity of the zeolite towards calcium removal in the presence of ammonium at low concentrations and calcium at higher concentrations, and breakthrough characteristics are presented. The results have revealed that removal of calcium, and hence hardness, through ion exchange with clinoptilolite under those circumstances is a promising alternative, with surface capacities reaching 11 mg calcium/g clinoptilolite.

Multiple Measurement of Anxiety and its Effects on Complex Verbal Learning

1976 ◽  
Vol 38 (3) ◽  
pp. 691-694 ◽  
Author(s):  
Charles A. Salter ◽  
Janet L. Meunier ◽  
Nancy M. Triplett
Keyword(s):  
Respiration Rate ◽  
Verbal Learning ◽  
Psychology Students ◽  
Self Report ◽  
Self Evaluation ◽  
Anxiety Measurement ◽  
Physiological Assessment ◽  
Different Types ◽  
Positive Correlations ◽  
Unobtrusive Observation

Some studies have found positive correlations between self-report anxiety and physiological anxiety during learning while others have not. This study used four measures: trait anxiety (IPAT Self-analysis Form), state anxiety (self-evaluation), physiological assessment (respiration rate), and unobtrusive observation by a confederate. 50 undergraduate psychology students (20 males and 30 females) worked on a German-English translation after which they were tested for memory of the German words exposed exactly five times each. The two self-report measures correlated with each other .313, and the two physical measures were correlated .683. But the self-report measures were negatively and nonsignificantly correlated with the physical ones, of which only respiration rate correlated with learning (–.308). Apparently social desirability needs can interfere with anxiety measurement in learning experiments and this may help explain the different findings about learning among studies which used different types of measures. These physiological ones seemed more accurate, perhaps because they are less easily controlled by the subjects themselves.

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