Minerals Montmorillonite Research Articles

Characteristics of Neogene clay materials in Northwest Bulgaria – new data for the areas near Bela and Staropatitsa villages

Clay materials have a variety of unique characteristics and have various applications in many industries. In this paper, we represent new data about the mineralogical and chemical characteristics of the Neogene clay materials from the areas of the villages of Bela and Staropatitsa, Northwest Bulgaria. The phase composition of the samples mainly consists of quartz and clay minerals, which in both sites are represented by smectite and kaolinite types, with mica, chlorite, illite, and potassium feldspars present. The chemical analysis indicated that silica and alumina were predominant in the analyzed samples, with medium contents of iron oxide. The percentage of MgO, K2O, and TiO2 content is explained by the presence of montmorillonite minerals, illite/mica, and anatase. The high values of the Chemical Index of Alteration (CIA) show that the clay materials underwent intense alteration. Further research into the chemical and mineralogical properties and the technical parameters of these clay materials is critical for understanding their formation processes, assessing their industrial applications, and improving the geologic and geotechnical assessments related to environmental implications.

Some black cotton soils of Ghana; A potential for use in geosynthetic clay liners

Black cotton soils contain the clay mineral montmorillonite which is the property of bentonite that makes it useful in geosynthetic clay liners. These soils occur in large quantities in Ghana. Importation of geosynthetic clay liners which contain bentonite as the major barrier material is expensive and a local alternative will have positive economic repercussions. The hydraulic conductivity of black cotton soils from Dowhenya, Prampram, and Tsopoli all in the Accra plains of Ghana were sandwiched between two geotextiles, tested, and compared to commercial bentonite. The results of the swell index test were 7.0mL/2g, 7.0mL/2g, 5.0mL/2g, and 30mL/2g for Dowhenya, Prampram, Tsopoli, and commercial bentonite respectively. The water content results obtained were 12.20%, 10.13%, 10.83%, and 17.48% for Dowhenya, Prampram, Tsopoli, and commercial bentonite respectively. The particle size distribution test results indicated that clay fractions are 83.4%, 71.3%, 72.9%, and 95.0% for Dowhenya, Prampram, Tsopoli, and commercial bentonite respectively. pH results determined are 7.86, 7.82, 7.90, and 10.24 for Dowhenya, Prampram, Tsopoli, and commercial bentonite respectively. The permeability of Dowhenya, Prampram, and Tsopoli black cotton soils was determined to be 1.03 X 10-9cm/s, 7.61 X 10-9cm/s, 2.04 X 10-9cm/s and these compare well to the commercial bentonite permeability value of 2.08 X 10-9cm/s tested under the same conditions. Based on the results, black cotton soils from these areas can be used as a potential substitute for commercial bentonite in geosynthetic clay liners.

Understanding the Nanoscale Affinity between Dissolved Organic Matter and Noncrystalline Mineral with the Implication for Water Treatment.

In recent decades, the concentration of dissolved organic matter (DOM) in aquatic ecosystems has gradually increased, leading to water pollution problems. Understanding the interfacial chemical processes of DOM on natural minerals is important to the exploration of high-efficiency absorbents. However, studying DOM chemical processes and adsorption mechanisms are still challenging due to the complex DOM structure and environmental system. Hence, we characterized the microstructure changes after the formation of amorphous calcium phosphate (ACP) at the interface of montmorillonite (Mt) minerals in a simulated environment system. Combined with atomic force microscopy and density functional theory (DFT) simulation, the mechanism of interfacial interaction between Mt-ACP and DOM was characterized at the molecular level. Moreover, we further evaluated the adsorption behavior of Mt-ACP as a potential adsorbent for organic matter. The comprehensive investigation of humic acid adsorption, intermolecular force, and DFT simulation is conducive to our understanding of the interfacial interaction mechanism between organic matter and noncrystalline minerals in aquatic environments and provides new perspectives on the application of clay-based mineral materials in pollutant removal under exposure from DOM.

Response of High Swelling Montmorillonite Clays with Aqueous Polymer

Expansive clays containing mineral montmorillonite exhibit swelling and shrinkage due to variations in the moisture content, leading to significant distresses. There has been a growing interest in chemical and polymer additives treated for high swelling montmorillonite clays in recent years. However, limited attention has been paid to the effect of polyacrylamide on the soil’s swelling behavior. Moreover, nontraditional methods of the soil treatment are applied for the rapid stabilization of soil. In this article, polyacrylamide polymer is used as an additive to expansive clays to control the swelling phenomenon. Three different percentages—2.5%, 5%, and 7.5%—of polymer are blended with oven-dried soil to determine Atterberg limits, compaction features, and swelling characteristics. Additionally, electrical impedance measurement is conducted on treated soil samples with different moisture contents. The electrical resistance of soils and polymer-treated soils is measured based on the electrical resistivity correlation of soils. Tests results for soils stabilized with polyacrylamide show that swelling is significantly reduced with increasing the additive content. Moreover, the addition of polymer improves resistivity of soil. Aqueous polyacrylamide can be utilized as an effective stabilization additive to enhance properties of expansive clays.

Molecular insights into histidine adsorption on Na-montmorillonite, anatase, and goethite

The adsorption of amino acids (AAs) on minerals plays a role in the geochemical processes that determine the availability of nutrients in the environment. Histidine can be used as typical basic AA because it is frequently detected in natural waters, soils, and sediments. Herein, the pH effects and time factor were analyzed to reveal the molecular-level mechanisms of histidine adsorption on Na-montmorillonite, anatase, and goethite. Attenuated total reflectance Fourier transform infrared (ATR–FTIR) flow-cell measurements, X-ray diffraction (XRD), and density functional theory (DFT) calculations were used to determine the adsorbed species structures and the time-dependent adsorption/desorption processes. The structures of adsorbed histidine were governed by pH conditions, but were not affected by time variations. The histidine adsorbed on the minerals was in the cationic (pH 4), neutral zwitterionic (pH 7.5), and anionic (pH 10.5) forms, which was consistent with those dissolved in solution at the same pH. Adsorption on the clay mineral montmorillonite was favorable due to the dominant interlayer adsorption mechanism at pH 4 and hydrophobic attraction (external basal surface) at pH 4–10.5. Histidine adsorption on the two metal (hydr)oxides was dominated by inner-sphere surface complexation, which involved one or two O atoms of the COO− group. The adsorbed histidine was in the monodentate form on anatase and in the bidentate form on goethite.

Impact of iron corrosion on swell pressure of compacted barmer bentonite induced with thermal history

The bentonite is compacted around the steel canister containing high-level waste to ensure the sealing of the canister by blocking the entry of harmful radiations emitted due to the reactions of active radionuclides. However, the canister continuously exhibits a high temperature (150 °C–200 °C) due to radioactive waste decay over a long time, which creates a thermal history on the surrounded compacted bentonite. Corrosion can generate changes in the bentonite buffer, which comes in direct contact with the canister and may lead to a change in its swelling ability. This study investigates the influence of corrosion products on the swell pressure of compacted bentonite specimens subjected to thermal history. Two Bentonite samples (B1 and B2) from the Barmer district of Rajasthan, India, were mixed with corrosion products and compacted at dry densities 1.5 Mg/m3, 1.75 Mg/m3 and 2.0 Mg/m3. These specimens were subjected to thermal histories at 110 °C and 200 °C and saturated with distilled water. The decrease in the swell pressure values was observed with the corrosion product and the increase in temperature of induced thermal history—comparatively, more time required for saturation in the presence of corrosion products than in its absence. The alteration in montmorillonite minerals might have occurred under the induced thermal history and corrosion reaction.

Natural protoberberine alkaloid–montmorillonite nanocomposite powders with AIE features for visualizing high-resolution latent fingerprints

Real-time and in-situ fluorescence visualization technologies have attention to in the forensic analysis of latent fingerprints (LFPs). The fingerprint powders with high performance and biocompatibility are essential for imaging LFPs with high definition and safety. In this work, five quaternary protoberberine alkaloid (QPA) derivatives were analyzed with reorganization energy and four-point calculations to explain the relationship between the substituent effect and luminescent properties and further resolve the luminous behaviors of four QPA-based natural products in solution. Thanks to the restriction of the intramolecular motions mechanism, aggregation-induced emission (AIE) active BBC nanoaggregates could sensitively detect explosive analog, 2,4,6-trinitrophenol, at a nanomolar level (9.8 nM of detection limit). Combined with natural montmorillonite (MMT) mineral powders, three levels of details for fingerprints were successfully imaged with solid-luminous BBC/MMT nanocomposites. The insight into the substituted effect of alkoxy groups on the QPA framework not only provides a new concept to design rotor-free AIE luminogens but also expands natural products and their nanocomposites into LFP and detection applications.

Thermogravimetric Characteristics and Pyrolysis Kinetics of Nigerian Oil Sands.

In the present study, the pyrolysis behavior of Nigerian oil sands was investigated using thermogravimetric analysis. This was done with the aim of deriving kinetic models that can be relevant in the development of the natural resource. The effects of different heating rates (10, 20, and 30 °C/min) on oil sand pyrolysis were studied. The results of the study indicated that three regions comprising low-temperature oxidation, devolatilization, and high-temperature oxidation were obtained at all heating rates. The peak temperatures were observed to rise with an increasing heating rate, a phenomenon described as thermal hysteresis. Mineralogical analysis showed the presence of diffraction peaks corresponding to chlorite, quartz, aragonite, dolomite, calcite, and montmorillonite minerals and the notable absence of expandable clay minerals which are known to pose problems during tailing management and the aqueous bitumen extraction process. The kinetic analysis showed that the activation energy increased with the degree of conversion, with the highest activation energy of 14.682 kJ mol-1. The Coats-Redfern kinetic model gave the best model fit for oil sand pyrolysis.

Prophylactic efficiency of the administration of vitamin, mineral and sorbent complexes on bone tissue in female rats against the background of chronic alcohol consumption

Among the general effects of alcohol use, it has a negative effect on the bone system, so the development of prevention methods is becoming an increasingly urgent problem. The present study was aimed at evaluating the efficiency of the preventive complexes for the bone system in chronic alcohol intoxication. The study was conducted on 2-month-old female rats for 104 days. Chronic alcoholism in animals was simulated by replacing drinking water with an ethanol solution, the concentration of which was gradually increased from 8–25%. The prophylactic was administered by introducing into the diet a complex of vitamins (P, C, D) and minerals (Cu, Mg, Zn, Se, Mn), the main component of which was crushed oyster shells processed with citric acid. The second prophylactic complex was the clay mineral montmorillonite in combination with vitamins P, C, D. The biochemical markers of resorption (elastase and acid phosphatase activity), osteogenesis (calcium content, alkaline phosphatase activity) and the state of the antioxidant system (catalase, superoxide dismutase, glutathione reductase activity, malondialdehyde content) were determined in bones (jaws and femurs). Chronic alcohol consumption led to an increase in the degree of atrophy of the alveolar process, a decrease in femur bone density due to a decrease in the mineral component in bone tissue, and did not affect the state of the lumbar vertebrae. Chronic alcohol intoxication led to a decrease in the level of calcium in the blood serum of rats, and to a decrease in the alkaline phosphatase activity and the calcium content in the bone tissue of the jaws and femur against the background of increases in the activities of acid phosphatase and elastase. A significant decrease in the activity of the main antioxidant enzymes (superoxide dismutase, catalase and glutathione reductase) in bone tissue of animals against the background of an increase in the malondialdehyde content under conditions of chronic alcoholization has been established. The use of the complex with crushed oyster shells effectively prevented atrophy ofthe alveolar process in the jaws, did not affect the morphometric parameters in the femur and vertebrae, but normalized the activities of serum alkaline phosphatase and catalase, bone elastase, acid phosphatase, superoxide dismutase and glutathione reductase against the background of restoring the levels of calcium and malondialdehyde both in the serum and in the bone tissue of rats subjected to chronic alcoholization. Prophylactic administration of the vitamin complex with montmorillonite had a much weaker effect on the studied indicators. The obtained research results allow us to conclude that the osteoprotective and antioxidant efficiency of the complex with crushed oyster shells is more pronounced than that of montmorillonite under conditions of chronic alcohol intoxication.

Comparative study of the cesium adsorption behavior of montmorillonite and illite based on their mineralogical properties and interlayer cations

Among clay minerals, montmorillonite (MMT) and illite are generally used to remove radioactive cesium (137Cs) from radioactive wastewater. The objectives of this study were to investigate the mineralogical properties of MMT and illite with their Cs adsorption behavior and then demonstrate the type of clay mineral that should be used for removing high- and low-concentrations of Cs. The Ca-type MMT used in this study was exchanged with sodium (Na), magnesium (Mg), and potassium (K) to compare the Cs adsorption behavior based on the interlayer cation type, including that of illite. The basal d-spacing (d001) of MMTs (swelling) ranged from 1.011 to 1.396 according to the interlayer cation type. Illite (non-swelling) had d001 of about 1.0 nm. Among the types, Na-MMT had the highest Cs adsorption capacity (204.67 mg/g), while illite exhibited the highest Cs distribution coefficient (Kd) (161.1 mL/g). The results indicated that the relative charge density of cations and interlayer properties, such as swelling and non-swelling, of clay minerals significantly affect Cs adsorption capacity and selectivity. Therefore, the selection of clay minerals should vary according to the type of high- and low-concentrated Cs wastewater. MMT and illite are advantageous for removing Cs from high- and low-concentration radioactive wastewater, respectively.

Properties of Sound Absorption Composite Materials Developed Using Flax Fiber, Sphagnum Moss, Vermiculite, and Sapropel.

To address the need to reduce consumption and pollution in the industrial sector, composite materials were created using a new type of raw materials-organic lake sediments (sapropel) as a binder; sphagnum moss, flax fiber, and vermiculite as a filler. The main application of these composite materials is for sound absorption and moisture buffering, but since they contain bio-based binders and fillers, they also work as carbon storage. Within the framework of this work, a total of 100 samples of composite materials were created. Fungicides-a biocide quaternary ammonium compound and its natural substitute montmorillonite mineral material were also added to the materials to improve microbiological stability. The mechanical sound absorption and microbiological properties of materials were investigated and compared to similar environmentally friendly materials, such as hemp-lime concrete (FHL), hemp magnesium oxychloride composite (MOC), and hemp magnesium phosphate cement (MPC). The results showed that sound absorption and mechanical and microbial properties of the created composite materials are sufficient for their intended use, with flax fiber and vermiculite composites showing more stable mechanical, sound absorbing, and microbiological stability properties than materials containing flax fiber and moss.

Adsorption of methane and carbon dioxide by water-saturated clay minerals and clay rocks

Understanding the effects of water on gas adsorption in geological media is of high importance in order to efficiently control numerous subsurface engineering process operating at gas/rock interfaces. Due to preferential interaction with clay surfaces, water fills their porous body, greatly reducing CH4 and CO2 adsorption capacity. In order to quantitatively describe CH4 and CO2 adsorption by hydrated clay minerals, this work proposes to rely on the mechanism of gas uptake by dissolution in pre-adsorbed pore water. This approach was employed to characterise water-saturated porous media of increasing complexity: mesoporous silica SBA-15 and silica gel with different pore sizes and geometry, isolated illite and montmorillonite and natural clay-rich rock (the Callovo-Oxfordian formation – COx, France) in powdered and crushed states. It was found that the solubility in water can reliably explain the CO2 uptakes by hydrated pore systems regardless of their nature as well as the CH4 uptakes, but only for solids with large mesopores and montmorillonite mineral. A so called “adsorption enhanced gas uptake in pore water” for CH4, exceeding its solubility in bulk water by a factor of 5–8, was observed for the systems with narrow pore sizes, highlighting the impact of surface energy on gas uptake and the occurrence of the interaction of weakly-soluble methane with the surface, promoting its uptake in comparison to pure dissolution.

Improvement in Soil Sub Grade Using Rice Husk Ash and Silica Fume by Soil Stabilization.

Abstract: Black cotton soil shows high swelling and shrinkage and less CBR value and strength due to presence of Montmorillonite mineral. Black cotton soil cannot be use for structural purpose in construction industry due to its expensive nature, therefore to control expensive behavior of the soil rise husk ash and silica fume is used in this experimental study. Rise husk ash used 0-15% by weight for observe experiment results and silica fume 0-12% by weight for observation of experiment results. Plasticity index, Free swell index of soil is decreasing with respect to RHA and SF addition and CBR value and shear strength of soil is increasing with respect to addition of RHA and SF . Optimum percentage of rise husk ash (RHA) and Silica fume (SF) observed as 12% and 9% respectively.

A Model of Stress-Damage-Permeability Relationship of Weakly Cemented Rocks under Triaxial Compressive Conditions.

To unravel the permeability variation mechanism of weakly cemented rocks (WCR), the paper conducted triaxial permeability tests on weakly cemented sandstones (WCS) collected from the Jurassic formation in northwest China. The paper identified the correlation of WCS permeability versus porosity, cementation structure, and mineral composition, further developing a model to characterize the WCS stress-damage-permeability relationship. The research indicated that the WCS permeability was initially high due to the naturally high porosity, large pore diameter, and loose particle cementation, thus favoring a significant decline as pore convergence in the compaction stage. In the residual stage, kaolinite and montmorillonite minerals disintegrated into water and narrowed fractures, causing a slight permeability increase from the initial to the maximum and residual stages. The WCS matrix fracturing was phenomenologically accompanied by clay mineral disintegration. By assuming that the matrix can be compressed, jointed, and fractured, the paper defined a damage variable D and accordingly developed a stress-damage-permeability relationship model that incorporated matrix compression, jointing, and fracturing. The model can describe the WCS permeability regime regarding the high initial permeability and slight difference of the maximum and residual permeabilities versus the initial.

Preparation of catalyst from natural montmorillonite mineral and its application in the synthesis of carbon nanosphere

In developed countries, nanoparticles derived from natural minerals and high-purity chemicals both are widely studied, while in developing countries like Mongolia, the natural minerals-based nanoparticles have more interest because of the low production cost and applicability of domestic natural minerals for their production. For the synthesis of natural mineral-based nanomaterials, it is important first to define the chemical composition and physical structure of local minerals and their possible processing route. We employed an environmentally friendly alkaline leaching procedure to recover silica from the clay mineral at 90°C for 24 hours. We applied an organic surfactant (CTAB) and a simple coprecipitation approach to form iron-doped silica nanoparticles. Consequently, we used iron-doped silica nanoparticles as a substrate and catalyst for the synthesis of carbon nanosphere at 750 °C for 1 hour in an argon and acetylene gas atmosphere. As a result, vast quantities of superhydrophobic carbon nanospheres (CNS) were obtained. The physicochemical properties of nanosilica substrate, non-functionalized carbon nanosphere, and functionalized carbon nanosphere (CNS) samples were characterized using XRD, XRF, SEM, EDS, TEM, and FTIR spectrometer. Iron-doped mineral-derived nanosilica particles demonstrated high catalytic efficiency and the potential to produce a large amount of value-added carbon nanospheres. Superhydrophobic CNS can be used in a variety of applications, particularly drug delivery; however, to use CNS in both aqueous and non-aqueous media, the superhydrophobic properties of CNS can be modified using different oxidizers. The changes in hydrophobicity of the CNS were examined and suggested possible oxidizing agents.

Nanoscale Interactions of Humic Acid and Minerals Reveal Mechanisms of Carbon Protection in Soil.

The concentrations of terrestrially sourced dissolved organic matter (DOM) have expanded throughout aquatic ecosystems in recent decades. Although sorption to minerals in soils is one major pathway to sequestrate soil organic matter, the mechanisms of organic matter-mineral interactions are not thoroughly understood. Here, we investigated the effect of calcium phosphate mineralization on humic acid (HA) fixation in simulated soil solutions, either with or without clay mineral montmorillonite (Mt). We found that Mt in solution promoted nucleation and crystallization of calcium phosphate (CaP) due to amorphous calcium phosphate clustering and coalescence on Mt surface, which contributed to the long-term persistence and accumulation of HA. Organic ligands with specific chemical groups on HA have higher binding energies to CaP-Mt than to CaP/Mt, according to dynamic force spectroscopy observations. Moreover, CaP-Mt formed in solution showed a great capacity for HA adsorption with a maximum adsorption quantity of 156.89 mg/g. Our findings directly support that Mt is crucial for DOM sequestration by facilitating CaP precipitation/transformation. This has an impact on how effectively we understand the long-term turnover of DOM and highlights knowledge gaps that might assist in resolving essential soil C sequestration issues.

Montmorillonite for Adsorption and Catalytic Elimination of Pollutants from Wastewater: A State-of-the-Arts Review

Clay minerals have been recognized as one of the cheap and effective materials for wastewater remediation. Among the various clay minerals, montmorillonite (MMT) has received much attention due to its wide availability, low-cost and promising properties such as high porosity, mechanical strength, and cation exchange capacity. Additionally, MMT has high swelling properties. These features make it an ideal material for wastewater remediation applications. In addition, it possessed good cationic exchange capacity, making it easier to interact with various molecules. MMT and its composites exhibited good selectivity and catalytic activity for contaminants elimination from wastewater. Surface modification and functionalization have been identified as a way to improve the MMT’s adsorptive performance and endow it with light and light-harnessing properties. Thus, MMT composites, especially metal and metal-oxide nanoparticles, have shown good adsorption and photocatalytic activity toward the elimination/mineralization of various contaminants such as dyes, pharmaceuticals, heavy metals, and other organic and inorganic species. As such, MMT and its composites can be adopted as potential materials for wastewater remediation.

Near-Infrared-II Activatable Symbiotic 2D Carbon-Clay Nanohybrids for Dual Imaging-Guided Combinational Cancer Therapy.

Two-dimensional (2D) nanomaterials hold great potential for cancer theranostic applications, yet their clinical translation faces great challenges of high toxicity and limited therapeutic/diagnostic modality. Here, we have created a kind of symbiotic 2D carbon-2D clay nanohybrids, which are composed of a novel 2D carbon nanomaterial (carbon nanochips, or CNC), prepared by carbonizing a conjugated polymer polydiiodobutadiyne, and a 2D layered aluminosilicate clay mineral montmorillonite (MMT). Intriguingly, with the formation of the nanohybrids, MMT can help the dispersion of CNC, while CNC can significantly reduce the hemolysis and toxicity of MMT. The symbiotic combination of CNC and MMT also leads to a synergistic anti-cancer theranostic effect. CNC has a strong absorption and high photothermal conversion efficiency in the second near-infrared region (NIR-II, 1000-1700 nm), while MMT contains Fe3+ that can facilitate the generation of reactive oxygen species from highly expressed H2O2 in tumor microenvironment. The nanohybrids not only enable a synergy of photothermal therapy and chemodynamic therapy to suppress the extremely rapid growth of RM1 tumors in mice but also allow for dual photoacoustic and magnetic imaging to guide the drug delivery and NIR-II irradiation execution, hence establishing a highly efficient and biosafe "all-in-one" theranostic platform for precision nanomedicine.

Growth and Welfare of African Catfish (Clarias gariepinus Burchell, 1822) under Dietary Supplementation with Mixed-Layer Clay Mineral Montmorillonite-Illite/Muscovite in Commercial Aquaculture

Juvenile African catfish (Clarias gariepinus Burchell, 1822) were reared within two experiments (a research facility and a local catfish farm, E1 and E2, respectively) for 102 d each under commercial recirculating aquaculture conditions. The mixed-layer clay mineral montmorillonite–illite/muscovite (1g557) was applied as a feed additive at concentrations of 0.5% and 2.0%, which were compared with an unsupplemented control (0.0%) over 70 d. For E1, feeding was automatic at night, while E2 was fed manually during the day. The growth and physiological welfare parameters of the fish were monitored, including the mortality, skin lesions, stress responses after confinement (plasma cortisol and glucose), and additional blood parameters. Tendentially, the most efficient growth in both the experiments was observed in the 0.5% groups, which performed slightly better than the controls (E1: 0.8% and E2: 3.2%) despite a lower nutrient content (p > 0.05). In E1, the negative skewness of the leptokurtic distribution also revealed the highest number of larger-sized fish per batch. Mortality was low in all the treatment groups (E1 control/0.5%/2.0%: 3.6%/4.9%/2.9%; E2 control/0.5%: 2.6%/5.5%). After only 29 d in E1, the number of skin lesions per fish decreased significantly (p < 0.05 between each of the 0.5% and 2.0% groups, compared to the control (E1 control/0.5%/2.0%: 1.2/0.8/0.8). In both E1 and E2, the number of lesions per fish decreased even further after 70 d, significantly between the treatment groups and the control (E1 control/0.5%/2.0%: 0.9/0.4/0.5 and E2 control/0.5%: 0.6/0.3). In E1, the cortisol and glucose concentrations increased strongly in all the groups due to the induced stress, whereas this was not evident in E2 based on the different sampling procedure. The additional blood parameters (aspartate aminotransferase, glutamate dehydrogenase, urea, calcium, phosphate, total protein, leucocytes, erythrocytes, hematocrit, cholesterol, triglycerides, sodium, potassium, and chloride) revealed no significant difference between the treatment groups in either experiment, indicating no negative effects of 1g557 on the organs or metabolism of the fish. Supplementation with 0.5% 1g557 in the common commercial feeds for African catfish increases growth performance (p > 0.05), reduces size variance, and supports fish welfare under different commercial aquaculture conditions in the present study.

Kinetic, equilibrium, adsorption mechanisms of RBBR and MG dyes on chitosan-coated montmorillonite with an ecofriendly approach

In this study, by modifying the montmorillonite mineral with chitosan, chitosan/montmorillonite composites were synthesized, and research was performed as to its usage as an adsorbent in removing Remazol Brillant Blue R and Malachite Green dyestuffs from aqueous solutions. SEM, FT-IR, XRD, and BET analysis techniques were utilized to determine the characteristics of the synthesized composite. The effects of different batch parameters such as initial pH value (2−9), contact time (5–120 min), initial dyestuff concentration (50–300 mg/ L), adsorbent dose (0.05–0.5 g/100 mL), and process temperature (293–313 K) on the adsorption process were examined. The optimum pH was 2 for RBBR, whereas it was 8 for MG. Also, the optimum removal time was 120 min for RBBR; it was 210 min for MG. As per the Langmuir isotherm model, the maximum adsorption capacity (qmax) was found as 332.58 mg/ g for RBBR, and it (qmax) was 400 mg/ g for MG. This capacity was interpreted as an indicator of usability in removing the RRBR and MG dyes specified in the study from wastewater. The results revealed that the equilibrium isotherm follows the Langmuir equation, and the kinetic model shows consistency with the pseudo-second-order equation. The thermodynamics of adsorption was studied, too. The experimental results demonstrated that CCS/MTs are suitable adsorbents for RBBR and MG removal from aqueous solutions because of their high adsorption capacity.