Saturation Capacity Research Articles

Association of Iron Profile with Type 2 Diabetes Mellitus:Review

This minireview assesses the correlation between iron profile levels and type 2 diabetes mellitus. Iron, ferritin, transferrin saturation, and total iron-binding capacity (TIBC) are examples of iron profiles. Every study included in this review shows that type 2 diabetics' blood serum has less iron overall and less iron-binding capacity. Conversely, the same studies' findings showed that individuals with type 2 diabetes had higher levels of ferritin in their blood serum. In terms of transferrin (iron) saturation, a number of studies show that it is rising, while a smaller number shows that it is falling in the blood serum of those who have type 2 diabetes. These investigations led to the conclusion that there is substantial evidence linking the iron profile to type 2 diabetic mellitus (T2DM). Reduced transferrin levels are connected to a lower risk of Type 2 Diabetes Mellitus, but higher serum iron, ferritin, and transferrin saturation are associated with an increased risk. There is also genetic evidence that links elevated systemic iron status to a higher risk of type 2 diabetes.

Differential Analysis of Various Moisture Phases on N2 Displacement of CH4 in Coal.

The aim of the study was to elucidate the impact of different moisture phases during gas injection on coalbed methane displacement. The coal samples were treated with two methods: water vapor adsorption and liquid water stirring. The differences in the coal samples treated with various moisture phases during gas injection for coalbed methane displacement were investigated by using the isothermal adsorption curves of CH4, N2, and H2O in coal and N2 displacement of CH4 in coal. The results indicate that variations in the gas adsorption capacity of coal are treated with different moisture phases. The gas adsorption capacities and displacement capacities of the coal samples treated with the water vapor adsorption methods are better than those treated with the stirring methods. In the isothermal adsorption experiment, for the coal samples treated with different moisture phases, at a moisture content of 2.75%, the saturated adsorption capacities of CH4/N2 are 0.204/0.189 (cm3/g), and at a moisture content of 5.63%, the saturated adsorption capacities of CH4/N2 are 0.151/0.139 (cm3/g). In addition, in the displacement experiment, for the coal samples treated with different moisture phases, at a moisture content of 2.75%, the difference in the total gas adsorption capacities is 0.62 cm3/g and the difference in the CH4 adsorption capacities is 0.473 cm3/g, and at a moisture content of 5.63%, the difference in the total gas adsorption capacities is 0.3 cm3/g and the difference in CH4 adsorption capacities is 0.22 cm3/g. For the coal samples treated with various moisture phases, the differences in the CH4/N2 adsorption and displacement capacities are greater at a moisture content of 2.75% than at 5.63%. Notably, the moisture phase has only a marginal influence on the CH4 desorption capacity and desorption rate. The study is important to understand the interactions between coal and moisture.

The characteristics of adsorption Cr(VI) by iron-modified and iron-doped phosphorus-based biochar biochar

ABSTRACT In this study, we evaluated the effect of the modification of biochar on the adsorption of Cr(VI) under weakly acidic conditions. Sesame straw biochar (BC) was modified by treatment with ferric chloride to produce iron-modified biochar (FBC) and ferric chloride and chlorapatite to produce iron-doped chlorapatite-modified biochar (FBCP). Analysis by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) showed that the adsorption mechanism of Cr(VI) by FBC and FBCP was reduction, physical adsorption, ion exchange, and functional group complexation. Experiments were performed to evaluate the kinetic, isothermal, and thermodynamic characteristics of adsorption, demonstrating that the adsorption of Cr(VI) by FBC and FBCP was a spontaneous endothermic reaction, consistent with the pseudo-second-order kinetic model and Langmuir model, and the process was dominated by monolayer chemical adsorption. The Langmuir model revealed maximum saturated adsorption capacities for Cr(VI) of 7.907 and 12.625 mg/g by FBC and FBCP, respectively, equating to 4.06 and 6.48 times the maximum saturated adsorption capacity of BC, respectively. Compared with FBC, the phosphate ions in FBCP also co-precipitated with Cr(III), further improving the removal efficiency of pollutants.

Iron Status and Risk of Heart Disease, Stroke, and Diabetes: A Mendelian Randomization Study in European Adults.

The relevance of iron status biomarkers for coronary artery disease (CAD), heart failure (HF), ischemic stroke (IS), and type 2 diabetes (T2D) is uncertain. We compared the observational and Mendelian randomization (MR) analyses of iron status biomarkers and hemoglobin with these diseases. Observational analyses of hemoglobin were compared with genetically predicted hemoglobin with cardiovascular diseases and diabetes in the UK Biobank. Iron biomarkers included transferrin saturation, serum iron, ferritin, and total iron binding capacity. MR analyses assessed associations with CAD (CARDIOGRAMplusC4D [Coronary Artery Disease Genome Wide Replication and Meta-Analysis Plus The Coronary Artery Disease Genetics], n=181 522 cases), HF (HERMES [Heart Failure Molecular Epidemiology for Therapeutic Targets), n=115 150 cases), IS (GIGASTROKE, n=62 100 cases), and T2D (DIAMANTE [Diabetes Meta-Analysis of Trans-Ethnic Association Studies], n=80 154 cases) genome-wide consortia. Observational analyses demonstrated J-shaped associations of hemoglobin with CAD, HF, IS, and T2D. In contrast, MR analyses demonstrated linear positive associations of higher genetically predicted hemoglobin levels with 8% higher risk per 1 SD higher hemoglobin for CAD, 10% to 13% for diabetes, but not with IS or HF in UK Biobank. Bidirectional MR analyses confirmed the causal relevance of iron biomarkers for hemoglobin. Further MR analyses in global consortia demonstrated modest protective effects of iron biomarkers for CAD (7%-14% lower risk for 1 SD higher levels of iron biomarkers), adverse effects for T2D, but no associations with IS or HF. Higher levels of iron biomarkers were protective for CAD, had adverse effects on T2D, but had no effects on IS or HF. Randomized trials are now required to assess effects of iron supplements on risk of CAD in high-risk older people.

Oyster shell-modified lignite composite in globular shape as a low-cost adsorbent for the removal of Pb2+ and Cd2+ from AMD: Evaluation of adsorption properties and exploration of potential mechanisms

A low-cost composite adsorption material has been synthesized from fishery wastes and natural minerals to address challenges such as ecological balance destruction caused by high concentrations of Pb and Cd in acid mine drainage (AMD), unreasonable use of low-caloric lignite, and environmental pollution caused by idle accumulation of oyster shells. This new adsorbent can effectively treat AMD by improving acidity and adsorbing Pb2+ and Cd2+. In this study, oyster shell-modified lignite composite in globular shape (OSL-G) was synthesized by using pyrolyzed oyster shell and lignite, with the addition of bentonite adhesive. The adsorption properties of OSL-G on AMD were evaluated, and the potential mechanism of OSL-G repairing AMD was explored. The results showed that when the mass ratio of oyster shell to lignite was 1:1, oyster shell-modified lignite composite (OSL) was synthesized at 900 °C for 20 min. When the adhesive content was 15.50 %, the roasting temperature was 640 °C, and the roasting time was 2.35 h, OSL-G was synthesized and the adsorption effect was the best. The OSL-G could effectively treat AMD with pH 4 ∼ 5 and initial Pb2+ and Cd2+ concentrations of 10 mg/L within 600 min at a dosage of 4 g/L. The OSL-G adsorption process followed the quasi-second-order kinetic model and the Freundlich model. The maximum adsorption saturation capacities of Pb2+ and Cd2+ were 107.2821 mg/g and 8.3777 mg/g at 298.15 K, respectively. The adsorption process was a multistep controlled spontaneous endothermic process. The potential mechanism was mainly the adsorption-condensation coexistence results of electrostatic adsorption, neutralization precipitation, ion exchange, and surface complexation. The removal rates of Pb2+ and Cd2+ of the recovered OSL-G (ROSL-G) were still high, reaching 57.26 % and 50.38 % after 5 times of adsorption–desorption, respectively. The applicability of ROSL-G after adsorption–desorption for other heavy metal components in AMD proved its good application potential. This study suggested that OSL-G can be used as a promising environmentally friendly adsorbent for AMD. This study provided a broad picture of the management and reuse possibilities of fishery wastes and natural mineral resources, and addressed established, current, and potential strategic needs, particularly in terms of sustainability challenges and ecological civilization construction.

Experimental and theoretical study on recovered nano amorphous selenium as efficient adsorbents for mercury capture from flue gas

The cost-effective removal of gaseous elemental mercury from coal-fired flue gas is crucial for environmental protection. In this study, nano amorphous selenium (nano-a-Se) adsorbent was recovered from desulfurization wastewater to remove Hg0 in flue gas. The results indicate that nano-a-Se has a high efficiency in the amorphous form with a saturated adsorption capacity of 2034.32 mg g−1. The Se utilization ratio of nano-a-Se reached 80% of the theoretical limit. Meanwhile, nano-a-Se exhibited high resistance to NO and SO2 poisoning. Moreover, the Hg0 removal mechanism of nano-a-Se was analyzed by experimental analysis and density functional theory (DFT) calculations. The results demonstrate that nano-a-Se can convert Hg0 into stable mercury selenide, a high-value by-product with little risk of mercury re-release. Therefore, nano-a-Se is expected to be a novel adsorbent with high efficiency in capturing Hg0, which can help realize the resource utilization of toxic elements from the environment.

Machine learning-based soil quality assessment for enhancing environmental monitoring in iron ore mining-impacted ecosystems

In November 2015, a catastrophic rupture of the Fundão dam in Mariana (Brazil), resulted in extensive socio-economic and environmental repercussions that persist to this day. In response, several reforestation programs were initiated to remediate the impacted regions. However, accurately assessing soil health in these areas is a complex endeavor. This study employs machine learning techniques to predict soil quality indicators that effectively differentiate between the stages of recovery in these areas. For this, a comprehensive set of soil parameters, encompassing 3 biological, 16 chemical, and 3 physical parameters, were evaluated for samples exposed to mining tailings and those unaffected, totaling 81 and 6 samples, respectively, which were evaluated over 2 years. The most robust model was the decision tree with a restriction of fewer levels to simplify the tree structure. In this model, Cation Exchange Capacity (CEC), Microbial Biomass Carbon (MBC), Base Saturation (BS), and Effective Cation Exchange Capacity (eCEC) emerged as the most pivotal factors influencing model fitting. This model achieved an accuracy score of 92% during training and 93% during testing for determining stages of recovery. The model developed in this study has the potential to revolutionize the monitoring efforts conducted by regulatory agencies in these regions. By reducing the number of parameters that necessitate evaluation, this enhanced efficiency promises to expedite recovery monitoring, simultaneously enhancing cost-effectiveness while upholding the analytical rigor of assessments.

Electrostatically directed assembly of macroporous skeleton structured copper selenide for elemental mercury sequestration from coal-fired flue gas

Decontamination of Hg0 from coal-fired flue gas remains an enormous challenge. It is an imperative pursuit to design adsorbents bearing an abundance of accessible chelating sites with a high affinity toward mercury, thus achieving both rapid uptake and high capacity for Hg0. Herein, an electrostatically directed assembly strategy was designed to construct Cu2Se decorated commercial polyurethane sponge (Cu2Se/PUS) as an efficient Hg0 trap. The surface coverage of Cu2Se on the Cu2Se/PUS can be rationally adjusted by turning the charge density of Cu2Se and PUS. The saturated Hg0 adsorption capacity of Cu2Se/PUS was achieved at 217.04 mg g−1 (normalized to the Cu2Se coating amount), which was much higher than that of powdery Cu2Se (43.66 mg g−1). Multiform selenium active sites (Se- and Se2-) and copper-terminated active centers of Cu2Se/PUS co-participated in Hg0 adsorption, instead of the individual role of Se- over powdery Cu2Se. The macroporous skeleton structure and the highly dispersed Cu2Se boosted the diffusion of mercury to the active sites for immobilization, thus accelerating the consumption of multiple active sites on the Cu2Se/PUS. This work not only provided an efficient Hg0 trap but also showed great inspiration for the potential of electrostatically directed assembly methods in constructing adsorbents for diverse environmental remediations.

Absorption of Ammonium by Three Substrates Materials in Constructed Wetland System

The adsorption characteristics of ammonia nitrogen for constructed wetland were studied with ceramsite, quartz sand, and gravel. The material was characterized using scanning electron microscopy and a BET-specific surface area analyzer. It was found that the surface of ceramide was coarser than that of quartz sand and gravel, and the internal pores were more developed. The specific surface area of ceramide (18.97 m2·g-1) was higher than that of quartz sand and gravel. In the pure ammonia nitrogen solution and Grade I B standard for the wastewater treatment plant effluent ammonia nitrogen solution of the effluent from the simulated sewage plant, the adsorption capacity of the three substrates was as follows:ceramsite > gravel > quartz sand. The saturated adsorption capacity (63.55 m2·g-1) of ceramides was the highest in the mixed solution. The adsorption process of ammonia nitrogen by ceramides accorded with the pseudo-second-order kinetic model (R2 of 0.99 in the pure ammonia nitrogen solution and 0.98 in the mixed solution). The Freundlich and Langmuir models were used to fit the isothermal adsorption results in a pure ammonia nitrogen solution. It was found that the Freundlich model described the adsorption characteristics of the ceramics more accurately than the Langmuir model (R2=0.93), indicating that the adsorption of ammonia nitrogen by the ceramics was multilayer adsorption. In conclusion, the adsorption capacity of ceramide was strong, and the adsorption capacity of ceramide in the mixed solution was 31% higher than that in the pure ammonia nitrogen solution, which was suitable to be used as the matrix filler of constructed wetland.

Removal of molybdenum by TBP-TRPO extraction in sodium isopolytungstate solution

A new process was proposed for extracting molybdenum from tungsten solutions in acidic tungsten-molybdenum mixed solution. The extraction ratio of molybdenum reached 70 % and the tungsten-molybdenum separation factors reached 400 with the hydrogen peroxide dosage of nH2O2/n(Mo) = 2 (nH2O2/n(W + Mo) = 0.3) for the molybdenum-containing isopolytungstate sodium solution. The experimental conditions resulted in the yield of only 20 % of the traditional method (nH2O2/n(W + Mo) = 1.5–2). The organic phases consisted of 2 % TRPO and 60 % TBP. The saturated extraction capacity of molybdenum was found to be 10 g/L. The solution of 0.3 mol/L sodium bicarbonate was used as the stripping agent. With the temperature of 25 ℃, stripping time of 6 min, and the phase ratio of (O/A)2, the stripping ratio of molybdenum was 90 % and that of tungsten was 70 %. The extraction mechanism of TBP-TRPO and the hydrogen peroxide coordination were analyzed using Raman and infrared analyses. The process has a high industrial potential due to its low hydrogen peroxide dosage, high molybdenum extraction ratio, high separation factor, and low cost.

Influence of the surfactant on structural characterizations and molecular adsorption properties of surfactant-templated NaY zeolite

Surfactant-templating strategy is an effective method to construct the hierarchical zeolite with controllable mesopores. In this work, the hierarchical NaY zeolites with the mesoporous size of ∼ 2.6 nm and ∼ 3.5 nm are obtained via the chemical etching and surfactant-templating process, and the formation mechanism of mesopores with controllable pore size is elucidated. The saturated adsorption capacity of toluene for H2C2O4-etched NaY-C10 and NH4HF2-etched NaY-C16 is 208 mg·g−1 and 215 mg·g−1, respectively. A new type of hierarchical NaY zeolite with excellent toluene adsorption properties is developed.

Synthesis and characterization of citric acid-modified chitosan Schiff base with enhanced antibacterial properties for the elimination of Bismarck Brown R and Rhodamine B dyes from wastewater

In this study, a new chitosan Schiff base with surface modification using citric acid was synthesized for efficient removal of pernicious dyes, namely Bismarck Brown R (BBR) and Rhodamine B (RhB), from wastewater. The physicochemical properties of the modified chitosan Schiff base were comprehensively investigated. Adsorption studies demonstrated that BBR adsorption occurred through monolayer formation, while RhB adsorption proceeded via multilayer formation on the heterogeneous surface. The synthesized adsorbent exhibited exceptional dye removal efficiency, with a Langmuir saturation capacity of 348 ± 11.0 mg.g−1 for BBR and 145 ± 18.44 mg.g−1 for RhB. Isotherm data fitting revealed consistency with the Langmuir isotherm model for BBR and the Freundlich isotherm model for RhB. Notably, the modified chitosan Schiff base showcased enhanced antibacterial properties, effectively inhibiting both gram-positive and gram-negative bacteria. The study's findings underscore the potential of this novel chitosan-based Schiff base as an efficient adsorbent for the removal of various dyes from wastewater, emphasizing its versatility and practical applicability in water treatment processes.

Tailored rapid recognizer and adsorbent of ultra-trace Hg2+ with novel benzothiazol-group decorated covalent organic polymers

Porous materials for fast detection and adsorption of Hg2+, due to their good sensitivity and high adsorption capacity, were currently developed as one of the best ways to solve Hg2+ pollution. Inspired by the structure of small-molecule B-1 demonstrating specific recognition towards Hg2+, the covalent organic polymers (COPs) material TB-COP was constructed for a better demonstration of Hg2+ detection and adsorption. The results indicated that TB-COP could accomplish rapid detection of Hg2+ in about 90 s, with a good linearity (R2 = 0.9993) and high sensitivity (LOD = 36 nM). Because the electron transfer between N and S atoms in the benzothiazole moiety, the recognition of TB-COP towards Hg2+ was achieved, which was further proved by DFT calculation. Though the COPs possess its excellent fluorescence properties, the saturated adsorption capacity for Hg2+ by TB-COP reached 150.38 mg·g−1 at pH = 7. More importantly, TB-COP could be approximately recycled 5 times in the Hg2+ adsorption-desorption cycle at room temperature, providing a new strategy to solve Hg2+ pollution.

Efficient uptake of 85Sr and 60Co using fabricated inorganic sorbent for reducing radiation doses of simulated low-level waste

The present study investigated the sorption behavior of 85Sr and 60Co radionuclides from aqueous solutions onto tin molybdate (SnMo) sorbent. SnMo has been synthesized using the precipitation method and was characterized using four analytical techniques including FT-IR, XRD, SEM, and XRF. The sorption studies applied on 85Sr and 60Co include the effect of shaking time, pH, concentration, and saturation capacity. The experimental data revealed that the sorption process was carried out after equilibrium time (180 min). The saturation capacity for 85Sr and 60Co is measured to be 58.1 and 52.2 mg g−1, respectively. The sorption behavior of studied radionuclides is dependent on pH values. Sorption kinetic better fit with the pseudo-second-order model. Furthermore, the sorption isotherm is better represented by the model proposed by Langmuir. The results of the desorption investigations indicated that the most effective eluents for achieving full recovery of investigated radionuclides were identified. Finally, the recycling results demonstrate the suitability of SnMo for affected sorbing of 85Sr and 60Co from aqueous solutions. All the obtained data clarify that the SnMo sorbent is an effective means of removing 85Sr and 60Co from liquid waste.

Soil Quality Index in Cocoa Crops

The main objective of this research is to develop a methodology to calculate a soil quality index in cocoa crops (Theobroma cacao L.), based on chemical properties such as pH, cation exchange capacity, organic matter, and percentage of base saturation, essential for the availability of nutrients in each cocoa tree. The problematic situation that causes this research is related to low yields per hectare, in small and medium-sized cocoa farms in the department of Huila – Colombia. A chemical quality index is proposed, which facilitates the analysis of the health behavior of the cultivated soil and nutrition of the cocoa plants, as a result of its interrelation with the physical and biological aspects. The proposed methodology is based on principal components analysis, to obtain weights and variable standardization equations, which evaluate 248 soil samples. The data indicate that in the cocoa producing land lots there are high pH values, cation exchange capacity and base saturation, but low levels of organic matter. It is concluded that in general the soils used showed moderate or low quality (52.42% and 11.29%, respectively), the rest showed high quality (36.29%). A soil intervention can improve its quality, however, the characteristic of the crop and the low levels of organic matter, requires recovering the properties and improving the health of the soil, if possible, through the implementation of regenerative agriculture, the object of future studies and research.

Effects of Deep Breathing Exercises On Oxygen Saturation and Functional Capacity in Hospitalized Patients with COPD

Objective: This study aims to examine the effect of deep breathing exercises on oxygen saturation and functional capacity in hospitalized patients with COPD. Methods: This quasi-experimental study included 37 male patients aged between 60-75 years. This study was conducted from 25th November 2022 to March 2023 at Arif Memorial Teaching Hospital, Mayo Hospital, and Gulab Devi Hospital. There were 6 sessions, 3 sessions per week. Each session was of 15-20 min. Deep breathing exercises were performed on each patient. Patients included in the study were hospitalized for exacerbated COPD without the use of NIV (non-invasive ventilation). The measuring parameters were; self-designed oxygen saturation measured by pulse Oximetry and dyspnea index for functional capacity. Results: By using paired sample t-test, there is a significant difference between oxygen saturation of COPD patients post-intervention with a mean value of -1.972±1.301 with a p-value of 0.05. By using a paired sample t-test, there is a significant difference between pre (23.18±4.77) and post-mean score (16.86±1.11) of dyspnea index with p-value < 0.05. Conclusion: The findings of the current study showed that deep breathing exercises were effective in improving oxygen saturation and functional capacity among hospitalized COPD patients. KEYWORDS: Deep breathing exercises, oxygen saturation, functional capacity, COPD.

Adsorption and desorption mechanism of toluene gas by iron modified activated carbon fiber

To enhance the adsorption performance of activated carbon fiber (ACF) on volatile organic compounds such as toluene, a series of Fex/ACF adsorption materials were prepared by impregnation and anaerobic atmosphere calcination. The various adsorption effects of Fex/ACF on toluene under different synthesis conditions were discussed, and both the modified and unmodified adsorption materials were characterized by using N2 adsorption–desorption isotherms, XRF, XRD, FT-IR, SEM, and XPS etc methods. The results indicated that iron modified ACF demonstrated the optimal adsorption performance when ACF was loaded with 3 % iron and calcined at 500 °C, and it achieved a saturated toluene adsorption capacity of 218.12 mg/g, which was 24 % higher than that of the unmodified sample. And its adsorption process of toluene followed Yoon-Nelson model. The adsorption capacity was maintained at approximately 70 % when four adsorption/desorption cycle tests. The toluene adsorption performance of Fe0.03/ACF-500 on toluene mainly involved surface adsorption (such as n-π interaction, and π-π interaction), pore filling, and complexation between the loaded metal iron and toluene.

Breakthrough Study of CO2 Adsorption and Regeneration Performance of Mn‐ and Ce‐Doped Ni–Al Layered Double Hydroxides Derived Mixed Oxides in Packed‐Bed Column

AbstractCarbon dioxide (CO2) capture is an important strategy to mitigate greenhouse gas emissions and reduce global warming effects. This study synthesizes two nanomaterials, Ce‐doped Ni–Al mixed metal oxide (CNAO) and Mn‐doped Ni–Al mixed metal oxide (MNAO), from Mn‐ and Ce‐doped Ni–Al‐layered double hydroxides using a co‐precipitation method followed by a calcination process. The materials are characterized using various techniques, such as High‐resolution transmission electron microscopy‐energy dispersive x‐ray spectroscopy/selected area electron dispersion (HRTEM‐EDS/SAED), X‐ray diffraction (XRD), x‐ray photoelectron spectroscopy (XPS), Brunauer‐Emmett‐Teller (BET), and attenuated total reflection Fourier transform infrared (ATR FT‐IR). The CO2 adsorption performance of the materials is evaluated using packed‐bed column experiments at the testing conditions of 13 vol% ± 1 vol% CO2 in N2 simulated flue gas, flow rate of 20 mL min−1, inlet pressure of 14.15 ± 0.1 psi, and temperature of 31 °C ± 2 °C. The results show that both CNAO and MNAO are promising nanomaterials for CO2 capture applications due to their high CO2 adsorption capacity and efficiency. CNAO has a higher saturation capacity of 11.4 mmol g−1 and a longer breakthrough time than MNAO, which has a saturation capacity of 10.0 mmol g−1. The doping of Ce and Mn enhances the CO2 adsorption capacity of the materials compared to the un‐doped Ni–Al mixed oxide. The mechanisms of CO2 adsorption are mainly linearly adsorbed CO2, bidentate, and monodentate or bulk carbonate formation, as revealed by ATR FT‐IR analysis. The regeneration performance results suggest that CNAO is more stable than MNAO under multiple regeneration cycles and more promising material for large‐scale CO2 capture applications.

Adsorption of anti-inflammatory and analgesic drugs traces in water on clay minerals

The aim of this study was to assess the adsorption of four non-steroidal anti-inflammatory drugs (NSAIDs), namely Paracetamol (PRC), Diclofenac (DIC), Ibuprofen (IBU), and Ketoprofen (KET), using both batch and continuous experiments with clay. Various analytical techniques, including XRD, FTIR, SEM coupled to EDX, and Zeta potential, were employed to characterize both raw and calcined clay. XRD and FTIR analyses confirmed the kaolinite nature of the clay. SEM data revealed a lamellar structure formed in the clay after calcination at 550 °C. Adsorption tests were conducted to determine the optimal adsorption conditions. Batch kinetics of adsorption demonstrated rapid adsorption of all four NSAIDs, with the highest adsorption occurring at pH 4 (DIC, IBU, and KET) and pH 6 for PRC, using a concentration of 20 mg L−1 of calcined clay. Additionally, the pseudo-second-order model provided the best fit for all NSAIDs adsorption processes. Maximum adsorption capacities, as determined by the Langmuir model, were 80 mg g−1 for PRC, 238 mg −1g for DIC, 138 mg g−1 for IBU, and 245 mg g−1 for KET. In fixed bed column studies, three dynamic models (Thomas, Adams-Bohart, and Yoon-Nelson) were utilized to describe the breakthrough curves, with linear regression used to identify key characteristics for process design. The fixed bed column adsorption study revealed that DIC exhibited the highest removal efficiency at 98%, while KET, IBU, and PRC were more persistent, with removal efficiencies of 77.1%, 76.7%, and 67.1%, respectively. The Thomas model was deemed appropriate for describing the breakthrough curve. These findings offer valuable insights into the interactions between clay and pharmaceuticals with varying physicochemical properties. They also provide information on the adsorption models, saturation, and adsorption capacities of various pharmaceuticals on natural clays, which can be crucial for further research and environmental remediation efforts.

Comparative study on the performance and properties of polyether and polyacrylate crude oil demulsifier

ABSTRACT Polyacrylate crude oil demulsifier is one of the hot topics in the research and development of demulsifier at present, there is a lack of systematic comparative study on performance and properties of polyether and polyacrylate crude oil demulsifier. In this paper, the demulsification performance and microscopic demulsification process of the two demulsifiers, namely polyacrylate P(MA-DBC) and polyether P199–59 are discussed. The demulsification performance of polyether P199–59 was superior to that of polyacrylate P(MA-DBC). The study of the microscopic process of demulsification established that for P199–59, the diffusion rate was faster, the saturated adsorption capacity was higher, the ability to destroy the oil-water interface film was stronger and the probability of water droplets collision coalescence was higher; therefore, it can achieve faster dehydration speed and higher dehydration rate than that of P(MA-DBC). The results of this comparative study are meaningful for improving the demulsification performance of polyacrylate demulsifier.