STRUCTURAL CHARACTERIZATION OF A BENTONITE DEPOSIT FROM THE EASTERN IRAN; COMPARISON WITH TWO REFERENCE BENTONITES

2021 ◽  
Vol 16 (1) ◽  
pp. 151-162
Author(s):  
Samira DOLATI ◽  
◽  
Mohsen KALANI
Keyword(s):  
Physicochemical Properties ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Mineralogical Composition ◽  
Industrial Applications ◽  
Exchange Capacity ◽  
High Yield ◽  
Fine Grained ◽  
Eastern Iran ◽  
High Fraction

Mineralogically, bentonites are dominated by smectites and due to characteristic textural and physicochemical properties of smectites (e.g. very small particle sizes, high cation exchange capacity) are of a great use in industrial applications. In this study, a bentonite sample was characterized with regard to the particle size distribution, mineralogical composition and cation exchange capacity in comparison with the data for the two internationally well-known bentonites representative for Na- and Ca-bentonites: the Mx-80 bentonite of Wyoming, USA and that of Milos, Greece, respectively. Results show a high fraction of fine-grained particles, which demonstrates high yield of purified clay. Mineralogically, the studied bentonite comprises mainly smectites and expandable illite-smectite mixed layer clay minerals. Main accessory minerals are calcite, silica polymorphs and zeolites. The specific surface area and cation exchange capacity values are 330.3 (m2g-1) and 42.2 (meq/100 g), respectively. It is concluded that the mineralogical, textural and the measured physicochemical properties of the studied bentonite is applicable to the applications in oil industry and its related environment maintenance related issues.

scholarly journals Effect of Low Zeolite Doses on Plants and Soil Physicochemical Properties

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2617
Author(s):  
Alicja Szatanik-Kloc ◽  
Justyna Szerement ◽  
Agnieszka Adamczuk ◽  
Grzegorz Józefaciuk
Keyword(s):  
Plant Growth ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Surface Area ◽  
Cation Exchange Capacity ◽  
N Fertilization ◽  
Exchange Capacity ◽  
First Year ◽  
Soil Physicochemical Properties ◽  
Water Holding

Thousands of tons of zeolitic materials are used yearly as soil conditioners and components of slow-release fertilizers. A positive influence of application of zeolites on plant growth has been frequently observed. Because zeolites have extremely large cation exchange capacity, surface area, porosity and water holding capacity, a paradigm has aroused that increasing plant growth is caused by a long-lasting improvement of soil physicochemical properties by zeolites. In the first year of our field experiment performed on a poor soil with zeolite rates from 1 to 8 t/ha and N fertilization, an increase in spring wheat yield was observed. Any effect on soil cation exchange capacity (CEC), surface area (S), pH-dependent surface charge (Qv), mesoporosity, water holding capacity and plant available water (PAW) was noted. This positive effect of zeolite on plants could be due to extra nutrients supplied by the mineral (primarily potassium—1 ton of the studied zeolite contained around 15 kg of exchangeable potassium). In the second year of the experiment (NPK treatment on previously zeolitized soil), the zeolite presence did not impact plant yield. No long-term effect of the zeolite on plants was observed in the third year after soil zeolitization, when, as in the first year, only N fertilization was applied. That there were no significant changes in the above-mentioned physicochemical properties of the field soil after the addition of zeolite was most likely due to high dilution of the mineral in the soil (8 t/ha zeolite is only ~0.35% of the soil mass in the root zone). To determine how much zeolite is needed to improve soil physicochemical properties, much higher zeolite rates than those applied in the field were studied in the laboratory. The latter studies showed that CEC and S increased proportionally to the zeolite percentage in the soil. The Qv of the zeolite was lower than that of the soil, so a decrease in soil variable charge was observed due to zeolite addition. Surprisingly, a slight increase in PAW, even at the largest zeolite dose (from 9.5% for the control soil to 13% for a mixture of 40 g zeolite and 100 g soil), was observed. It resulted from small alterations of the soil macrostructure: although the input of small zeolite pores was seen in pore size distributions, the larger pores responsible for the storage of PAW were almost not affected by the zeolite addition.

Characteristics of variably saturated granular bentonite after long-term storage at near-field relevant temperatures

Clay Minerals ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 343-361 ◽  
Author(s):  
M. Valter ◽  
M. Plötze
Keyword(s):  
Physicochemical Properties ◽  
Cation Exchange ◽  
Surface Area ◽  
Cation Exchange Capacity ◽  
Elevated Temperatures ◽  
Near Field ◽  
Exchange Capacity ◽  
Hydraulic Permeability ◽  
Cation Composition ◽  
Retention Capacity

AbstractBentonite is a potential material for use in the engineered barrier of radioactive waste repositories because of its low hydraulic permeability, self-sealing capability and retention capacity. It is expected that bentonite would react at the elevated temperatures accompanying the radioactive decay in the nuclear waste. The presented study was started in order to improve understanding of the coupled influence of temperature and (pore) water on the physicochemical and mineralogical properties of bentonite during thermal treatment under near-field relevant conditions. Granular Na-bentonite MX-80 was differently saturated (Sr = 1–0.05) and stored at different temperatures (50–150°C) in a closed system. Upon dismantling after different periods of time (3 to 18 months), mineralogical characteristics, cation exchange capacity and content of leachable cations, as well as physicochemical properties such as surface area and water adsorption were investigated.The results showed a high mineralogical stability. A slight conversion from the sodium to an earth alkali form of the bentonite was observed. However, considerable changes in the physicochemical properties of the bentonite were observed, particularly by treatment above the critical temperature of 120°C. The cation exchange capacity decreased during heating at 150°C by approximately. 10%. The specific surface area dropped by more than 50%. The water uptake capacity under free swelling conditions showed a slight tendency to lower values especially for samples heated for more than 12 months. The water vapour adsorption ability in contrast drops by 25% already within three months at T = 120°C. These changes are mostly related to the variations in the interlayer cation composition and to smectite aggregation processes. The observed alterations are rather subtle. However, temperatures ⩾ 120°C had a remarkable negative influence on different properties of MX-80.

Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics

Clay Minerals ◽  
2019 ◽  
Vol 54 (4) ◽  
pp. 369-377 ◽  
Author(s):  
Maja Milošević ◽  
Predrag Dabić ◽  
Sabina Kovač ◽  
Lazar Kaluđerović ◽  
Mihovil Logar
Keyword(s):  
Specific Surface ◽  
Cation Exchange ◽  
Surface Area ◽  
Specific Surface Area ◽  
Cation Exchange Capacity ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
Mineralogical Characterization ◽  
Mineralogical Study

AbstractThis study focuses on the mineralogical characterization of four raw clay samples from Dobrodo deposit, Serbia. Several analytical methods were applied to determine the chemical and mineralogical composition, morphology and physical properties (colour, plasticity, specific surface area, particle size and cation-exchange capacity) of the clay samples. Kaolinite, smectite and illite are the predominant phases in all of the samples studied that contain between 60.2 and 87.1 wt.% of clay. Quartz, feldspars, paragonite and Ti- and Fe-bearing phases were also identified. The relatively high SiO2/Al2O3 mass ratio indicates abundant quartz. The cation-exchange capacity of the samples varied between low and moderately charged clay minerals (12–52 mmol 100 g–1) with specific surface area values ranging from 94 to 410 m2 g–1. The plasticity index values (11–23%) suggest low to moderate plasticity. Preliminary results show that most of the raw clay from Dobrodo deposit might be suitable for use in ceramic applications.

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

scholarly journals Effects of Tree Forest Plantations on Soil Physicochemical Properties in the Arboretumof Ruhande,Southern Province of Rwanda

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Nsengimana Venuste
Keyword(s):  
Organic Carbon ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Bulk Density ◽  
Soil Ph ◽  
Tree Species ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Available Phosphorus ◽  
Soil Physicochemical Properties

Different tree speciesare blamed to have negative effects on soil ecosystems by changing soil physicochemical properties, and hence soil quality. However, few researches to verify this statement were done in Rwanda. This study provides prior information on the effects of planted forest tree species on soil physicochemical properties. It was conducted in the Arboretum of Ruhande, in southern Rwanda. Soil cores were collected in plots of exotic, native and agroforestry tree species. Collected soils were analysed for soil pH, total nitrogen, organic carbon, available phosphorus,  aggregate stability, bulk density, soil humidity, cation exchange capacity, and soil texture. Soils sampled under exotic tree species were acidic, richin soil organic carbon, and in soil available phosphorus. Native and agroforestry tree species offer better conditions in soil pH, soil water content, cation exchange capacity, clay and silt. Less variations in soil total nitrogen and soil bulk density were found in soils sampled under all studied forest types. Research concluded that studiedtree species have different effects on soil physicochemical parameters. It recommended further studies to generalize these findings. Key words: soil, exotic, native, agroforestry, soil properties

scholarly journals THE CATION EXCHANGE CAPACITY OF THE GREEK ZEOLITIC ROCKS

2007 ◽  
Vol 40 (2) ◽  
pp. 723 ◽  
Author(s):  
A. Filippidis ◽  
N. Kantiranis ◽  
M. Stamatakis ◽  
A. Drakoulis ◽  
E. Tzamos
Keyword(s):  
Cation Exchange ◽  
Clay Minerals ◽  
Cation Exchange Capacity ◽  
Diffraction Method ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
Area 5 ◽  
Type Zeolite ◽  
Saturation Method ◽  
Positive Correlations

Forty two zeolitic rock samples, from the Prefectures ofEvros, Rhodope, Samos and Cyclades, have been investigated for their cation exchange capacity (CEC, in meq/100g) and the mineralogical composition (wt.%), using the Ammonium Acetate Saturation method and Powder X-ray Diffraction method, respectively. HEU-type zeolite (heulandite-clinoptilolite) was found in Ρ etrota area (43-89 wt.%, CEC 101- 217), Samos island (34-91 wt.%, CEC 93-217), Pentalofos area (68-74 wt.%, CEC 124-202), Metaxades area (47-64 wt.%, CEC 119-140) and Thira island (33 wt.%, CEC 118). Mordenite was found in Samos island (64 wt.%, CEC 150), Polyegos island (61 wt.%, CEC 136), Thira island (56 wt.%, CEC 130), Milos island (45 wt.%, CEC 97), Kimolos island (30 wt.%, CEC 96) and Feres area (5 wt.%, CEC 22). Analcime was found in Samos island (27-71 wt.%, CEC 104-285) and Darmeni area (16 wt.%, CEC 62). Chabazite was found in Samos island (66 wt.%, CEC 243). HEU-type zeolite+mordenite were found in Feres area (45-74 wt.%, CEC 132-209), Samos island (81 wt.%, CEC 184), Thira island (72 wt.%, CEC 177), Polyegos island (66 wt.%, CEC 153) and Skaloma area (51-60 wt.%, CEC 126-143). HEUtype zeolite+phillipsite were found in Samos island (47 wt.%, CEC 170) and HEUtype zeolite+analcime were found in Samos island (55 wt.%, CEC 129). The CEC of the zeolitic rocks show positive correlations with the type of zeolite and the microporous minerals (zeolites+micas+clay minerals) content, mainly affected by the zeolites and to lesser extent by micas and clay minerals.

scholarly journals Effect of Salmonella on Decomposition of Poultry Litter

2018 ◽  
Vol 10 (1) ◽  
pp. 51-60 ◽  
Author(s):  
M. Mushtaq ◽  
H. Kasur ◽  
R. A. Khan ◽  
A. Khalid ◽  
M. K. Iqbal
Keyword(s):  
Physicochemical Properties ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Poultry Litter ◽  
Exchange Capacity ◽  
Degree Of Polymerization ◽  
Human Pathogens ◽  
Humification Index ◽  
Nitrogen Ratio ◽  
The Impact

Chicken litter is a significant source of nutrients for production of crops and to reduce the impact of human pathogens on environment. The physicochemical properties of poultry litter mixture compost was assessed against the maturity and stability indices such as carbon nitrogen ratio (C/N), nitrate (NO3), ammonia (NH3), ash, Cation Exchange Capacity (CEC), Humification Index (HI), Humification Rate (HR) and Degree of Polymerization (DP). The use of Salmonella significantly improves the humification process and physicochemical properties of final compost product are better in comparison to control trial. The most prominent effects was the fast rise in temperature from mesophilic to thermophilic stage was accompanied by an increase in NH4+-N that gradually decrease near the maturation phase. Moreover, the decrease in carbon and nitrogen ratio and increase in DP, CEC, HI, HR, phosphorous and potassium was also observed. A significant correlation was found between the maturity and stability parameters like C: N ratio, cation exchange capacity, humification index, degree of polymerization, humification rate and nitrate. Therefore, it is acclaimed that isolated microorganisms Salmonella from poultry litter promote the stable compost formation.

scholarly journals PREPARATION OF SOME VIETNAMESE MONTMORILLONITES

2010 ◽  
Vol 13 (1) ◽  
pp. 17-21
Author(s):  
Mai Thi Hoang Vo ◽  
Thach Ngoc Le
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Adsorption Capacity ◽  
Surface Area ◽  
Crystalline Structure ◽  
Cation Exchange Capacity ◽  
Exchange Capacity ◽  
Solid Catalyst

Montmorillonite is a "green" solid catalyst and support used in many organic reations. In this paper, we describe the method to prepare two acid-activated montmorillonites from Binh Thuan and Lam Dong clays. We still prepared some cation exchanged montmorillonites as Fe3+ Zn 2+ and Al 3+. The Vietnamese montmorillonites and K-10, KSF (two commercial Fluka montmorillonites) were determinated simultanneously on some physicochemical properties such as crystalline structure, chemical composition, cation exchange capacity, adsorption capacity, porisity, surface area and acidity. The results shows that the quality of Vietnamese montmorillonites are equivalent with K-10 and KSF.

scholarly journals The Influence of Basalt Powder on the Physicochemical Properties of Impoverished Oxisoils from Ngaoundéré (Adamawa - Cameroon)

2021 ◽  
pp. 307-315
Author(s):  
Dalil Adoulko ◽  
Simon Djakba Basga ◽  
Rigobert Tchameni ◽  
Jean Pierre Nguetnkam
Keyword(s):  
Physicochemical Properties ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Block Design ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Grain Size Analysis ◽  
Control Soil ◽  
Exchangeable Bases ◽  
Saturation Rate

The present study aims at assessing the fertilizing potential of basalts on impoverished oxisoils from Ngaoundéré (Adamawa, Cameroon). This specifically involves the application of finely ground basalts on impoverished oxisoils and monitoring changes in physicochemical properties during six months. An experimental design which consisted in a randomized complete block design is constituted of three series of four treatments each one: the control (ST), the control soil mixed with 100 g of finely ground basalt (T0 + BA_10), the control soil mixed with 200 g of finely ground basalt (T0 + BA_20), the control soil mixed with 300 g of finely ground basalt (T0 + BA_30). Each treatment was replicated ten times in every serie. The control treatment is only soils of Ng, collected at the top soil and without any basalt application. They are clayey, acid and display an average CEC. The basalt is rich in silica (47.52%), Calcium (8.22%), Magnesium (4.03%), sodium (4.01%), potassium (2.42%) and displays average content in alumina (16.54%) and iron (11.1%). The experiment was carried out in pots, and the incubated soil samples were analyzed after 0, 1, 2, 4 and 6 months. The analyzes mainly focused on the physicochemical parameters (Grain size analysis, pH, Cation exchange capacity (CEC), the sum of exchangeable bases (SBE) and the saturation rate (V). Obtained results indicated that the application of basalt greatly improved the chemical properties of oxisoils from Ngaoundéré: the pH changes from acidic (5.5) to weakly acidic (6.5); the saturation rate, as well as the sum of exchangeable bases and the cation exchange capacity increased. Physicochemical properties of the soil are closely accompanied by an increase in fertility. It appears that 10 and 20% treatments are the most efficient treatments. Thus, the basalts from Manwi can be recommended as petrofertilizer to improve the chemical properties of impoverished soils and especially for plants requiring alkalis and alkaline earth.

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