Adsorption of Organic Compounds on Refined Latvian Clay

2018 ◽  
Vol 788 ◽  
pp. 83-88
Author(s):  
Oskars Leščinskis ◽  
Ruta Švinka ◽  
Visvaldis Švinka
Keyword(s):  
Methyl Orange ◽  
Zeta Potential ◽  
Adsorption Capacity ◽  
Clay Minerals ◽  
Organic Compounds ◽  
Clay Mineral ◽  
Rhodamine B ◽  
Ph Value ◽  
Ftir Spectra ◽  
Ph Values

Clays are materials consisting of clay minerals and non-clay minerals. Clay mineral fraction is considered to be a nanofraction. Clay minerals can be used for water purification and treatment. Description and characterization of 3 different Latvian clay nanosized minerals from 3 different geological periods (clay Liepa from Devonian period, clay Vadakste from Triassic period and clay Apriki from Quaternary period) as well as their adsorption capacity concerning organic compounds such as methyl orange and rhodamine B are summarized. Nanosized clay mineral particles were obtained using sedimentation method. Particle size distribution, zeta potential and FTIR spectra is given. The adsorption tests of above mentioned organic compounds were carried out in water solutions at 3 different pH values. The adsorption values were determined by means of UV-spectrophotometric technique. Zeta potential values for clay minerals Apriki, Liepa and Vadakste are -40.9 mV, -49.6 mV and -43.0 mV, respectively. FTIR spectra show similar tendencies for all 3 clay minerals. The best adsorption capacity concerning methyl orange and rhodamine B were in solutions with a pH value of 2, whereas at neutral and alkaline pH values adsorption in 24 hours was not observed.

Common and Different in Latvian Clay Minerals

2018 ◽  
Vol 762 ◽  
pp. 268-272 ◽  
Author(s):  
Oskars Lescinskis ◽  
Ruta Švinka ◽  
Visvaldis Švinka
Keyword(s):  
Zeta Potential ◽  
Clay Minerals ◽  
Clay Mineral ◽  
Method Comparison ◽  
Mineralogical Composition ◽  
Nitrogen Adsorption ◽  
Ftir Spectra ◽  
Quaternary Period ◽  
Xrd Phase Analysis ◽  
Dta Analysis

Clays are materials consisting of clay minerals and non-clay minerals. Some applications allow to use raw clay others require to separate clay minerals from non-clay minerals. Clay mineral fraction is considered to be a nanofraction. Description and characterization of 3 different Latvian clay nanosized minerals from 3 different geological periods (clay Liepa from Devonian period, clay Vadakste from Triassic period and clay Apriki from Quaternary period) are summarized. The main mineral in these clays is illite, however the presence of kaolinite is observed and its quantity depends on geological period in which clays formed. Nanosized clay mineral particles were obtained using sedimentation method. Comparison of mineralogical composition, BET nitrogen adsorption, zeta potential, DTA/TG analysis and FTIR spectra is given. XRD phase analysis results were very close to each other and shows that mineral of illite is more than that of kaolinite. BET nitrogen adsorption data shows that clay minerals of Apriki has the highest specific surface area (81 m2/g), whereas clay minerals of Vadakste has it the lowest (43 m2/g). Zeta potential values for clay minerals Apriki, Liepa and Vadakste are-40.9 mV, -49.6 mV and-43.0 mV, respectively. DTA analysis and FTIR spectra show similar tendencies for all 3 clay minerals.

Adsorption of rhodamine B and Cr3+ ion onto graphene/chitosan composite

2020 ◽  
pp. 1-12
Author(s):  
Yanji Li ◽  
Meng Ni ◽  
Qiang He ◽  
Xiang Li ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Rhodamine B ◽  
Ph Value ◽  
Removal Rate ◽  
Ion Concentration ◽  
Particle Diffusion ◽  
Solution Ph ◽  
Magnetic Chitosan ◽  
Correlation Degree ◽  
Simulated Wastewater

Graphene and chitosan acted as the adsorbents for simulated wastewater with rhodamine B. The novel material produced by freeze-drying obviously outperformed graphene and chitosan in treating rhodamine B. Factors (e.g., contaminant concentration, reaction time, solution pH value, adsorption dose and temperature) overall impacted the adsorption. The optimal conditions for graphene-chitosan treatment of dyes included the concentration of pollutants at 400 mg/L, the dose of adsorbent as 5 mg, the solution pH at 4 and at 25∘C, and for 12 h, in which the maximal treatment amount reached 858.00 mg/g. The adsorption processes of Chitosan/graphene composites and magnetic Chitosan/graphene composites for simulated wastewater from Rhodamine B reactor followed Langmuir and Freundlich models, respectively. The in-particle diffusion model shows that the adsorption process of the composites for Rhodamine B simulated wastewater is not determined by either surface diffusion or in-particle diffusion. The magnetic Chitosan/graphene composites exhibit high recyclability, which can be respectively reused 3 times and 5 times and retain 80% adsorption capacity after being administrated with Rhodamine B simulated wastewater. By analyzing grey correlation degree, it is demonstrated that the concentration of pollutants and the reaction temperature critically affect the adsorption capacity. The electrochemical treatment with graphite rod for the Cr3+ was under the initial voltage of 30.6 V, at the pH of 5.59, and at the temperature of 18.5∘C; the removal rate of the samples was nearly 62.35% with the chromium ion concentration declined from 0.3333 g/L to 0.1255 g/L.

Characterization of clays by organic compounds

Clay Minerals ◽  
1981 ◽  
Vol 16 (1) ◽  
pp. 1-21 ◽  
Author(s):  
G. Lagaly
Keyword(s):  
Ion Exchange ◽  
Clay Minerals ◽  
Organic Compounds ◽  
Clay Mineral ◽  
Dye Adsorption ◽  
Organic Reactions ◽  
Layer Charge ◽  
Preliminary Identification

AbstractMany problems—from soil research to ceramics—require a reliable characterization of the clay minerals involved. This can be done using four clay-organic reactions: (i) staining tests and dye adsorption; (ii) glycerol and glycol adsorption; (iii) intercalation; (iv) alkylammonium ion exchange. Dye adsorption (staining tests) and glycerol adsorption allow a preliminary identification of the clay mineral groups. Intercalation reactions indicate minute differences between kaolins which cannot be detected by XRD and DTA. Alkylammonium ion exchange provides the best method for characterizing smectites and is sensitive to changes in the layer charge.

Enhancing the Degradation of Rhodamine B by Hydrodynamic Cavitation with CCl4 Augmentation

2013 ◽  
Vol 864-867 ◽  
pp. 1244-1252
Author(s):  
Shu Jun Zhang ◽  
Li Shen ◽  
Wen Juan Gong
Keyword(s):  
Rhodamine B ◽  
Ph Value ◽  
Fold Increase ◽  
Hydrodynamic Cavitation ◽  
Inlet Pressure ◽  
Kinetic Rate ◽  
Ph Values ◽  
First Order Kinetics ◽  
Kinetic Rate Constants ◽  
Degradation Reaction

The degradation of Rhodamine B, a common pollutant existing in industrial wastewater, has been explored using a hydrodynamic cavitation reactor combined with CCl4treatment. The effects of CCl4concentration, operating pH values, inlet pressure, initial temperatures and initial RhB concentration were investigated. The result shows that the removal of RhB increases from 70.78% to 80.38% with increasing CCl4concentrations during hydrodynamic cavitation. Degradation of RhB with CCl4treatment increased as the operating pH value and its initial concentration decreased, a 7-fold increase (from 0.22×102min1to 1.68×102min1) in the kinetic rate constants were found at pH values ranging from 4.0 to 2.0. In addition, RhB degradation with CCl4treatment increased as the inlet pressure and temperature increased. From the present work, we conclude that the RhB degradation reaction follows a pseudo-first-order kinetics, and the mechanisms of CCl4enhancement are subsequently discussed.

scholarly journals Adsorption Behaviors of 17α-Ethinylestradiol in Sediment-Water System in Northern Taihu Lake, China

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Yonghua Wang ◽  
Liangfeng Hu ◽  
Qiuying Wang ◽  
Guanghua Lu ◽  
Yi Li
Keyword(s):  
Adsorption Capacity ◽  
Taihu Lake ◽  
Ph Value ◽  
Water System ◽  
Freundlich Isotherm ◽  
Hydroxyl Group ◽  
High Concentration ◽  
Competitive Effects ◽  
Adsorption Sites ◽  
Ph Values

Adsorption behavior of 17α-ethinylestradiol (EE2) in northern Taihu Lake sediment was analyzed by using batch equilibrium experiment. Freundlich isotherm could describe the adsorption thermodynamic behavior of EE2 in sediment. Sediment organic matter (SOM) contents had important impacts on the adsorption capacity for EE2. The pH values also influenced the adsorption capacity for EE2. Increase of pH value could decrease the EE2 adsorption, which might be due to the electrostatic repulsion between the anionic form of EE2 and sediments with negative charge under high pH values. Competitive effects of bisphenol A (BPA) on EE2 adsorption were further analyzed. The results showed that low concentration BPA did not have significant influences on EE2 adsorption. However, high concentration BPA could reduce EE2 adsorption, which might be due to the similar molecular diameter of BPA with adsorption sites and one more benzene ring with a hydroxyl group in BPA. These results provide primary information of EE2 adsorption in sediment-water system in Taihu Lake, which is useful for the environmental risk assessment and management of EE2 in studied area.

scholarly journals Effect of Chitosan/BSA Addition on the Physical Stability of Sunflower Oil Emulsions

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Fengyan Zhou ◽  
Guo Li ◽  
Jianying Huang
Keyword(s):  
Particle Size ◽  
Bovine Serum Albumin ◽  
Zeta Potential ◽  
Sunflower Oil ◽  
Storage Stability ◽  
Emulsion Stability ◽  
Ph Value ◽  
Physical Stability ◽  
Ph Values ◽  
Oil Emulsions

Proteins and polysaccharides are important ingredients and additives in food field. The aim of this study was to study the effect of chitosan and bovine serum albumin (BSA) solution on the physical stability of sunflower oil emulsions at different pH values, temperatures, and BSA/chitosan ratios during 20-day storage in terms of their storage stability, zeta potential, particle size, and microstructure. The results showed that pH, protein/polysaccharide ratio, and temperature significantly influenced the physical stability of emulsions at lower pH. The emulsion stability decreased as the test temperatures increased, and the storage stability of BSA/chitosan coated oil emulsions was obtained when the ratio was from 8 : 1 to 1 : 1 under 4°C for 20-day storage when pH values were 3.0 and 4.0. Droplet flocculation happened with the increase of chitosan addition and pH value.

Characteristics of wood-silica composites influenced by the pH value of silica sols

Holzforschung ◽  
2018 ◽  
Vol 72 (4) ◽  
pp. 311-319 ◽  
Author(s):  
Jun Jiang ◽  
Jinzhen Cao ◽  
Wang Wang
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Dimensional Stability ◽  
Colloidal Particle ◽  
Ph Value ◽  
Surface Hardness ◽  
X Ray ◽  
Ph Values ◽  
First Case ◽  
Silica Sols

AbstractSouthern pine (Pinusspp.) sapwood samples were impregnated with silica sols with known zeta potential and particle size distribution at various pH values (3, 5, 7, 9, 11 and 13) to produce wood-silica composites (WSiCs). The morphological and chemical properties of the composites were evaluated by scanning electron microscopy-energy dispersive X-ray (SEM-EDXA) and Fourier transform infrared (FTIR) spectroscopy. The overall performance of the composites was characterized by X-ray diffraction (XRD) and thermogravimetric (TG) analysis, and dynamic wettability tests, and their dimensional stability and surface hardness were also investigated as well. The pH value of the sols had a remarkable effect on the distribution of zeta potential and colloidal particle size, and on their penetration and distribution in the wood. The composites produced at pH 5 and pH 11 show relatively better impregnability and overall properties. In the first case the compatibility with the wood pH (ca. 5) is relevant, and at these pH values are the sol’s particle sizes low. Sols with pH around 13 resulted in inferior properties, such as increased water absorption, high thermal degradation and poor dimensional stability. This could be ascribed to wood degradation under high alkaline conditions. The results were discussed in view of the colloidal particle redistribution and the interaction between silica sol and wood.

Electrokinetic Properties and Their Effect on Thermal Conductivity of Nanofluids

2008 ◽  
Author(s):  
S. M. Sohel Murshed ◽  
Kai Choong Leong ◽  
Chun Yang
Keyword(s):  
Thermal Conductivity ◽  
Zeta Potential ◽  
Effective Thermal Conductivity ◽  
Electrolyte Concentration ◽  
Ph Value ◽  
Deionized Water ◽  
Ph Values ◽  
Nacl Concentration ◽  
Effects Of Ph ◽  
Similar Decrease

This paper presents the effects of pH value, surfactant, and electrolyte concentration on zeta potential and effective thermal conductivity of nanofluids. The zeta potential of TiO2 (15 nm) nanoparticles in deionized water of different pH values was measured and the iso-electrical point was found to be between 4.9 and 5.2. The results show that the higher the electrolyte concentration, the smaller the particle zeta potential, which results in increased agglomeration of particles. The enhanced thermal conductivity of TiO2/deionized water-based nanofluids was found to decrease with increasing pH value or electrolyte concentration. For example, for 0.2 volume %, the thermal conductivity of this nanofluid was found to decrease from 5.5% to 2.5% when the pH value was increased from 3.4 to 9. A similar decrease (≈ 2%) in thermal conductivity was observed when NaCl concentration was increased from 0.01 mM to 10 mM. The presence of a surfactant showed considerably larger enhancement of the effective thermal conductivity compared to that of nanofluids without surfactant.

Technology of Modified Orange Peel Adsorption Treatment in Wastewater Containing Zinc

2012 ◽  
Vol 610-613 ◽  
pp. 1540-1545
Author(s):  
Rui Yu Jia ◽  
You Hong Lin ◽  
Wei Zhang
Keyword(s):  
Adsorption Capacity ◽  
Ph Value ◽  
Orange Peel ◽  
Sorption Process ◽  
Optimal Conditions ◽  
Adsorption Time ◽  
Initial Concentration ◽  
Ph Values ◽  
Wide Range ◽  
Adsorption Treatment

Using modified flavedo as the adsorbent , the sorption process of Zn2+Superscript text by modified flavedo in wastewater containing heavymetals was studied. The effects of various factors in Zn2+Superscript text adsorption , such as adsorbtion time , temperature , pH value , initial Zn2+ concentration , and pretreatment,were analyzed. The results showed that the pretreatment of modified raised adsorption capacity , and the adsorption capacity was suitable for wastewater with a wide range of pH values. The rate of removal of Zn2+Superscript text reached 98% when the Zn2+ initial concentration was under 100mg/L. The optimal conditions for Zn2 + adsorptionSuperscript text by Modified orange peel were a wastewater pH value of 5.5 , at 25 °C, an adsorption time of 60 minutes , and a dosage of modacrylic flavedo of 2 g/ L.

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