Polymer Dosage Research Articles

ВЛИЯНИЕ ПРИМЕНЕНИЯ ПОЛИМЕРНЫХ СТРУКТУРООБРАЗОВАТЕЛЕЙ НА ФИТОТОКСИЧНОСТЬ АГРОЧЕРНОЗЕМА

The use of polymer structure–forming agents in agriculture is a promising method of reducing soil erosion. An important condition for application is the assessment of the phytotoxicity of the polymer composition. The effect of polymer compositions VPRG® (VPRG) and VPK-402® (VPK) on the growth of the Trifolium rubens plant was studied in the laboratory on agrochernozem. The degree of influence was assessed by the change in the dry mass of the upper part of the plants relative to the control. It was found that the use of VPRG in doses of 106, 212 and 424 kg/ha per 10 m3 of water, and VPK in doses of 280 and 560 l/ha per 10 m3 of water did not have a toxic effect on the germination and growth of the Trifolium rubens plant. The dry weight of the upper part of the plants grown using these doses of polymers exceeded the control values by 1.14–1.47 times. The use of ВПК at a dose of 1120 g/ha per 10 m3 of water, as well as mixtures of polymers of VPRG and VPK in doses of (106 kg/ha of VPRG)/(280 l/ha of VPK) per 10 m3 of water and (424 kg/ha of VPRG)/(140 l/ha of VPK) per 10 m3 water had a negative effect on the growth of the red clover plant: the weight of the dry mass of the upper part of the plant decreased by 1.1–2.0 times relative to the control.

The Relationship between Gelation Behavior and the Amount of Polymer Dose per Silica Surface Area of "Shake-Gels" Consisting of Silica Nanoparticles and Poly(Ethylene Oxide).

The understanding and control of the rheological behaviors of colloids and polymer mixtures is an important issue for scientific interests and industrial applications. Aqueous mixed suspensions of silica nanoparticles and poly(ethylene oxide) (PEO) under certain conditions are interesting systems called "shake-gels", whose states vary reversibly between sol-like and gel-like under repeated shaking and being left to stand. Previous studies have indicated that the amount of PEO dose per silica surface area (Cp) is a crucial parameter for the formation of shake-gels and the relaxation time from gel-like to sol-like states. However, the relationship between the gelation dynamics and the Cp values has not been fully investigated. To determine how the gelation dynamics are affected by the Cp, we measured the time taken for silica and PEO mixtures to gelate from the sol-like to gel-like states as a function of the Cp under different shear rates and flow types. Our results show that the gelation time decreased with increasing shear rates and depended on the Cp values. Moreover, the minimum gelation time was found around a certain Cp (=0.03 mg/m2) for the first time. The finding suggests that there is an optimum Cp value at which the bridging of silica nanoparticles using PEO is significant, and thus, the shake-gels and stable gel-like states are most likely to form.

Preparation and application of novel thermo-sensitive molecularly imprinted polymer for selective extraction of omeprazole from pharmaceutical formulation and biological fluids

ABSTRACT Omeprazole selective molecularly imprinted polymer was synthesized by polymerization using 2-hydroxyethyl methacrylate as a monomer, N-vinylcaprolactam as a thermo-sensitive polymer, and N, N′-methylenebisacrylamide as cross-linker, respectively. This study aimed to develop a novel polymer as a nanoadsorbent for the extraction of omeprazole in biological and pharmaceutical samples. To achieve maximum extraction recovery of the drug, the Nd:YAG pulsed laser irradiation was used to convert adsorbent particles into smaller sizes using water solvent at different irradiation times. Properties of prepared thermo-sensitive molecularly imprinted polymer were characterized by different analyses. The optimal extraction conditions were thermo-sensitive molecularly imprinted polymer dosage of 0.01 g, a cross-linking agent of 0.15 g, contact time of 15 min, eluent of methanol, the temperature of 25°C, initial drug concentration of 20 mg L−1, and solution pH of 4. The sorption isotherms and selective recognition of thermo-sensitive molecularly imprinted polymer were investigated in detail. Sorption results fitted well into the linearized Langmuir equation. The selectivity experiment has shown that the sorption capacity and selectivity of thermo-sensitive molecularly imprinted polymer to omeprazole were higher than those of bicalutamide and prednisolone. A high-performance liquid chromatography-ultra-violet detector method was validated and utilized for analysis of drug extracted from biological and pharmaceutical samples. The method was linear in the range of 0.5–80 mg L−1 with a relative standard deviation value of 0.094 and a limit of detection and a limit of quantification of 0.9 and 30 µg L−1, respectively. The recovery of omeprazole drug ranged from 94.3%, 99.2%, and 98.1%, respectively, in human plasma, human urine, and pharmaceutical samples.

Morphological changes of liver and spleen under the impact of dextran-polyacrylamide polymers and their effects as carriers of silver and gold nanoparticles

The possibility of usage of polymer nanocomposites is being intensively studied today with a purpose of their application in medicine, espessialy in oncology. At the experimental stage it is important to determine the mechanisms of the influence of such compounds on the body and their own possible undesirable effects. Aim – to study the effect of the treatment with maximal doses of the dextran-polyacrylamide polymers and their effect as carriers of silver and gold nanoparticles on the spleen and liver. Histological examination of micropreparations of the spleen and liver by the standard method with hematoxylin-eosin staining was made. As a result of the treatment with nonionic (D-g-PAA) and anionic (D-g-PAA (PE)) polymer matrices, changes which occurred in the spleen indicate an increase in the production of all blood cells. These phenomena were absent when silver and gold nanoparticles were included in the matrix. In the liver, treatment with D-g-PAA and D-g-PAA (PE) caused a disorder of hepatic circulation, focal infiltration by inflammatory cells and death of hepatocytes by necrosis. The addition of nanoparticles triggered other mechanisms of alteration, which manifested themselves in excessive accumulation of glycogen, fatty infiltration of hepatocytes, and cell death, mainly through apoptosis. However, along with this, signs of an incomplete regenerative response of the liver were revealed. Morphological changes caused by the treatment with maximal doses of the tested substances indicate their toxic effect, especially on the liver. Further researches are needed to establish the optimal doses and the frequency of their administration, which can be used for therapeutic purposes, including the interaction of studied polymers with blood cells.

Microstructure refinement and shrinkage mitigation of alkali-activated slag paste by superabsorbent polymer

This paper investigates the effects of superabsorbent polymer (SAP) dosage, particle size, addition method, and absorption status on the properties and microstructure of alkali-activated slag (AAS) pastes. The results show that incorporating SAP can mitigate the autogenous shrinkage and short-term drying shrinkage of the AAS pastes, mainly depending on the SAP dosage and size. The release of activator can promote the geopolymerisation around the SAP particles, which improves the local micro-hardness of the pastes and reduces the amount of capillary pores. This consequently densifies the microstructure around the SAP particles and mitigates the shrinkage of the AAS pastes. The large SAP particles are found to release activator to a farther distance than the small ones, which is more effective in mitigating the autogenous shrinkage. The promoted conversion from mesopores to gel pores in the paste with large SAP is also beneficial to reducing the driving force of autogenous shrinkage. By contrast, the addition method and absorption status of SAP particles have marginal impacts on the autogenous shrinkage as the released activators travel a similar distance within the AAS pastes. Moreover, adding SAP particles increases the number of gel pores and macropores regardless of their size or absorption status, leading to an increased long-term drying shrinkage and a weakened mechanical property of the AAS paste. Overall, the findings of this study can guide the mix design and preparation of AAS materials with SAP.

Cationic Pullulan Derivatives Based Flocculants for Removal of Some Metal Oxides from Simulated Wastewater

Modified polysaccharides have been increasingly used as flocculants in wastewater treatment due to their non-toxicity, low price, biodegradability, etc. However, the pullulan derivatives are less used in wastewater purification processes. Therefore, this article presents some data regarding FeO and TiO2 particle removal from model suspensions by some pullulan derivatives with pendant quaternary ammonium salt groups, trimethylammonium propyl carbamate chloride (TMAPx-P). The influence of the polymer ionic content, dose, and initial solution concentration as well as of the dispersion pH and composition (metal oxide content, salts, and kaolin) on the separation efficacy were considered. UV-Vis spectroscopy measurements have shown a very good removal efficacy of TMAPx-P for the FeO particles (around 95% and more), irrespective of the polymer and suspension characteristics; a lower clarification of the TiO2 particles suspension (removal efficiency between 68% and 75%) was noticed. Both the zeta potential and the particle aggregates size measurements revealed the charge patch as the main mechanism which governs the metal oxide removal process. The surface morphology analysis/EDX data provided supplementary evidence regarding the separation process. A good removal efficiency (90%) of the pullulan derivatives/FeO flocs for the Bordeaux mixture particles from simulated wastewater was found.

Metal Cation and Surfactant-Assisted Flocculation for Enhanced Dewatering of Anaerobically Digested Sludge

Flocculation and dewatering of anaerobically digested sludge is known to be a major cost factor in the economy of wastewater treatment plants. Hence, several endeavors have been underway in search of affordable and effective alternatives. This study focuses on the effects of different metal cations, including FeCl3, CaCl2 and MgSO4, on the dewaterability of digested sludge. The effects of these metal flocculants were also investigated in the presence of co-polymers and surfactants, which can be considered the novelty of this study. The polymers and surfactants investigated in this study were emulsion polymer, CTAB and SDS. Sampling and characterization of digested sludge was conducted, and total solid (TS), volatile solid (VS), dewaterability in capillary suction time (CST), total dissolved solids (TDS), chemical oxygen demand (COD), pH and conductivity of the unconditioned digested sludge samples were determined. The dewaterability of FeCl3, CaCl2 and MgSO4 conditioned digested sludge samples were compared, and MgSO4 conditioned digested sludge showed better dewaterability compared to the other two metal conditioning agents at a pH of 6.8. The dewaterability was further improved by the addition of emulsion polymer (EMA 8854), cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS). Fe Cl3 was found to perform better under an acidic pH of around 3. The dual conditioning using polymer and CTAB resulted in better dewaterability, with CaCl2 as metal conditioning agent. Moreover, the effects of pH, metal dose and polymer dose on the dewaterability of digested sludge were also investigated. The effects of metal and polymer conditioning on the particle size of the sludge flocs was also investigated. Optimum dewatering performance was achieved for metal doses of 0.16 v/v, 0.075 v/v and 0.16 v/v for FeCl3, CaCl2 and MgSO4, respectively, and a corresponding CTAB dose of 0.1 v/v and EMA dose of 15 kg/TDS were found to be the optimum. SDS as a polymer conditioning agent resulted in the deterioration of dewatering performance.

Grafting PEG and alkyl comb polymers onto bleached wood pulp fibres

AbstractComb polymers were prepared by reacting a poly(ethylene‐alt‐maleic anhydride) with alkyl amines or poly(ethylene glycol) (PEG) amines. The resulting polymers were used to modify bleached softwood kraft pulp fibre surfaces by catalyst‐free grafting in a process suitable for pulp mill implementation. Pulp fibres were impregnated with a polymer solution and cured above 100°C. High grafting yields were obtained despite having up to 88% of the anhydride groups consumed by amine derivatization. Grafting yields were more than 90% when the polymer dosage was <13 g/kg (dry polymer/dry fibre) for alkyl derivatives and < 38 g/kg for PEG derivatives. We propose that the upper dosage limit for efficient grafting reflects the need for direct contact between cellulose and every polymer chain for ester linkage formation. For a given polymer dosage, the cured pulp sheets had a maximum wet tensile index, TImax, when either curing time or temperature was increased. Both the alkyl and PEG derivatives fit the power law for the wet TImax~βΓru0.54–0.62 where β values were the estimated conversion of succinic acid moieties to anhydrides when the pulp sheets were cured, and Γru is the dimensionless polymer content that is numerically equal to the amount of applied polymer in mmol repeat units/g dry fibre. However, high polymer dosages give experimental TImax values that fall below the power law, irrespective of curing intensity, because the pulp sheets contain unfixed polymer chains that lubricate fibre/fibre joints, lowering wet strength.

Application of biopolymer in turbidity removal and sludge settling behaviour of travertine-processing wastewater: Performance optimization using response surface methodology (RSM)

A flocculation process was performed to treat travertine-processing effluents with a high concentration of suspended solids using an eco-friendly biopolymer. The experiments were conducted through a standard jar test procedure to optimize the process parameters for sludge volume index (SVI) and turbidity removal. The effects of mixing time, suspension pH, and polymer dosage on treatment efficiency were investigated using central composite design, a standard technique in response surface methodology. The constructed response model was tested using the analysis of variance (ANOVA). Using the Design-Expert tool, the coefficients of regression models were computed. The Fischer value (F-value) was used to evaluate the significance and validity of the predicted model, while the coefficient of determination (R2) was applied to estimate the model significance by comparing the predicted data with the measured data. The optimized parameters obtained were polymer dose of 276.20 mg/L, suspension pH of 8.60, and mixing time of 4.20 min. The optimal SVI and turbidity values obtained were 1.36 mL/g and 2.99 NTU, respectively. Additionally, R2 values for SVI and turbidity were determined as 0.9337 and 0.8654, respectively. Also, the difference between adjusted R2 values and predicted R2 was less than 0.2. Validation tests showed that the response surface methodology is an effective method for optimizing the flocculation mechanism.

Operational optimization at the Nenäinniemi wastewater treatment plant's tertiary disc filter phosphorus removal installation to reduce chemical consumption.

Instrumentation, automation and control in municipal wastewater treatment can result in large resource, cost and energy savings. Feedforward and feedback control algorithms were implemented together with turbidity and phosphorus analysers to control the chemical dose at the tertiary stage of the Nenäinniemi wastewater treatment plant, consisting of coagulation, flocculation and microsieve filtration. This optimization lowered the coagulant dose by 70% and the polymer dose by 36% compared to manual adjustments of the chemical dosing. Effluent total phosphorus (TP) and total suspended solids (TSS) concentrations were lowered by 20-30%. With the control system in operation, the annual savings in coagulant and polymer were in the range of 100 and 1.4 tons, respectively. Conducting automated CIP on the media at an economical break-even interval of approximately 20 days was also important to further lower energy usage and operational costs.

Asphalt Mixtures Fatigue Life Considering Various Environmental Impacts.

The pavement structure during the colder seasons (winter) or in regions located above sea level is commonly affected and deteriorated by many environmental factors. Two prominent factors are water and frost (weather) or road salt (maintenance). According to the article's literature review, there are only a few studies related to water and frost or road salt impact on mineral asphalt mixes considering fatigue. Most of the tests were performed on mixes containing common road asphalt or only one binder content level was investigated. There are no articles that investigate this problem comprehensively including new asphalt, its content levels, or production technology. Based on the literature review, the main problem regarding degradation impact on mixtures fatigue life was stated. The investigation was performed using two proprietary experimental methods allowing approximates in situ conditions regarding environmental impacts. A dynamic four-point bending fatigue test was applied to evaluate degradation considering fatigue. The investigation was performed using four coarse-graded asphalt mixtures (asphalt concrete AC 22) which differed in binder type (35/50 WMA, 35/50, 25/55-60, and 25/55-80 HIMA), content level (4.24%, 4.03%, 3.82%), and production technology (hot and warm). Regarding the results obtained, the authors proposed a degradation ratio regarding fatigue life variability. Based on the obtained results and ratio used, it was found that both interactions caused a significant fatigue life decrease-in the worst case, over tens of percent. Furthermore, it was found that asphalt mixture resistance to environmental factors depends on binder type, its content level, air void content, and discussed impact. Moreover, asphalt mixtures' susceptibility to degradation (fatigue) is extreme at lower binder content levels and accelerates due to air void content increase. In the article, it was also stated that the highest resistance was reached by a mixture with highly modified asphalt (25/55-80 HIMA). It was also found that the SBS polymer dosage increase in the asphalt matrix enhances asphalt mixture resistance to environmental impacts. The least resistant to the environmental degradation mixture was WMA (35/50 WMA).

Dextrin‐graft‐poly(2‐dimethylamino ethyl acrylate‐co‐2‐acrylamido‐2‐methyl propane sulfonic acid) polymer: A potential adsorbent for the fast removal of nitrophenols from aqueous medium

AbstractA graft copolymer is synthesized by grafting a mixture of 2‐(dimethylamino) ethyl acrylate (DMAEA) and 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS) monomers onto the dextrin, polysaccharide backbone via free radical polymerization process using potassium peroxydisulfate (KPS) as radical initiator in aqueous phase. Various characterization techniques like 1H and 13C NMR, FT‐IR, SEM, EDAX, and XRD analysis are used to characterize the copolymer. The polymer is used as an adsorbent for the removal of nitrophenols namely ortho‐nitrophenol (ONP), para‐nitrophenol (PNP), and 2,4‐ dinitrophenol (DNP) from their water solutions. Adsorption dynamics, kinetics, isotherms, and thermodynamics are studied. The maximum nitrophenol adsorption occurs at time 80 min, temperature 45°C, pH 3.5 (DNP), and 4.5 (ONP and PNP), polymer dose 30 mg/L. The nitrophenol adsorption data are well‐fitted with the Langmuir isotherm model with maximum adsorption capacity () 215.26 mg g−1 for ONP, 223.60 mg g−1 for PNP, and 288.24 mg g−1 for DNP. The equilibrium kinetics follow pseudo‐second‐order kinetic model. Thermodynamic values unfold that the following nitrophenol adsorption onto the polymer surface is spontaneous and endothermic in nature. The value of Gibb's free energy for the nitrophenol adsorption is in the range of −6.5 to −9.5 kJ mol−1. The preferential nitrophenol adsorption by the copolymer is followed in the order ONP<PNP<DNP.

Approximation of hindered zonal settling rates for flocculated inorganic/organic composite suspensions in inertial flow conditions

Inorganic/organic composite nuclear wastes have poor settling properties which hinder major UK decommissioning operations. Improving the settling properties of these wastes and the accurate prediction of settling rates is therefore key. However, constricted access and limited monitoring capability in radioactive environments limits the use of primary material, necessitating the use of surrogate test materials. Herein, an organic laden nuclear waste test material was characterised by examining the surface chemistry, morphology and settling behaviour. A large molecular weight polyacrylamide polymer was deployed to aggregate the organic laden nuclear waste test material. The polyacrylamide successfully flocculated the test material, increasing the zonal settling rate and decreasing the turbidity by one and two orders of magnitude respectively at optimum polymer dose conditions. Whilst displaying steric stabilisation beyond the performance maxima, reductions in flocculant performance were small with no indication of permanent stabilisation at five times the optimum dose. To mitigate risk, it is critical to understand the dynamics of the settling process. Given the porous, fractal nature of the agglomerates, fractal modified hindered settling models were assessed in order to improve predictions at low solids concentrations. In particular, predictive models using drag coefficients compatible with creeping and inertia flow regimes were utilised in tandem with structural and size data to quantify the impact of neglecting inertia drag as favoured by previous literature. It was found that at low solids concentrations, the inter-particulate spacing was significant and that inertial flow conditions were integral considerations to achieve close first-order approximations of zonal settling rate.

Effect of dosage of super absorbent polymer on self-consolidating concrete: Correlation between compressive strength and rheological properties

This research investigates the super absorbent polymer effect on self-consolidating concrete's compressive strength and rheological properties (SCC). The SCC mixes contained four different dosages of super absorbent polymer (SAP). The Rheological properties of SCC changed by adding SAP, and also workability decreased due to water absorption from the mix by dry SAP. The compressive strength of concrete increased, especially in air curing and gunny bag curing, at all curing ages but decreased in water curing. Experimental investigation measured the yield stress, plastic viscosity, slump flow and V-funnel time to assess the rheology of concrete and compressive strength in three curing regimes. In this study effect of super absorbent polymer on rheology and compressive strength of SCC in water curing, air curing, and gunny bag curing regimes has been revealed. Correlations have been found among Plastic viscosity, Yield stress, Slump flow value, V-funnel time, and compressive strength of concrete at 28 days of curing in three curing regimes.

Numerical Simulation of High Concentration Polymer Flooding in Oilfield Development

The field test of high concentration polymer flooding has the characteristics of high cost, long cycle and irreversibility of the reservoir development process. In order to ensure the best development effect of the development block, this paper simulated and calculated the high concentration polymer flooding development case of the polymer flooding pilot test area through numerical simulation research, and selected the best case through the comparison of various development indicators. The simulation results showed that the larger the polymer dosage and the higher the concentration, the better the oil displacement effect. The best injection method in the construction process was the overall injection of high concentration polymer. The test area should implement high concentration polymer oil displacement as soon as possible. The research results provided theoretical guidance for the future development and management of the pilot area.

A Data Analytics Pipeline to Optimise Polymer Dose Strategy in a Semi-Continuous Multi-Feed Dewatering System

A Data Analytics Pipeline to Optimise Polymer Dose Strategy in a Semi-Continuous Multi-Feed Dewatering System

Dual functionality of ferrocene-based metallopolymers as radical scavengers and nanoparticle stabilizing agents.

The beneficial redox properties of ferrocene-based polymers have been utilized during in situ preparation of metallic nanoparticles, while such redox features also indicate a great promise in applications as free radical scavengers. Here, colloidal dispersions of an antioxidant nanozyme composed of amidine-functionalized polystyrene latex (AL) nanoparticles, negatively charged poly(ferrocenylsilane) (PFS(-)) organometallic polyions, and ascorbic acid (AA) were formulated. The AL was first functionalized with PFS(-). Increasing the polymer dose resulted in charge neutralization and subsequent charge reversal of the particles. The strength of repulsive interparticle forces of electrostatic nature was significant at low and high doses leading to stable colloids, while attractive forces dominated near the charge neutralization point giving rise to unstable dispersions. The saturated PFS(-) layer adsorbed on the surface of the AL (p-AL nanozyme) enhanced the colloidal stability against salt-induced aggregation without affecting the pH-dependent charge and size of the particles. The joint effect of PFS(-) and the AA in radical decomposition was observed indicating the antioxidant potential of the system. The immobilization of PFS(-) deteriorated its scavenging activity, yet the combination with AA improved this feature. The results indicate that p-AL-AA is a promising radical scavenger since the high colloidal stability of the particles allows application in heterogeneous systems, such as in industrial manufacturing processes, where antioxidants are required to maintain acceptable product quality.

Influence of polymer modification of complex fertilizer on the efficiency of phosphorus and potassium use by winter wheat on the southern chernozem

In modern conditions of unprecedented challenges, an alternative to the technological degradation of fertilizer application systems can be the development of original forms of long-acting fertilizers. Despite significant progress in the adaptation of progressive systems of agrochemical impacts, the use of traditional forms of mineral fertilizers does not allow using the full potential of the introduced nutrients, since the processes of incomplete denitrification, immobilization and leaching (leaching) of the main macronutrients (NPK), along with the action of urease, lead to unproductive loss of nutrients in the soil. In addition to economic losses, there are negative environmental consequences – eutrophication of water bodies, emission of greenhouse gases. The studies were carried out in 2022 under production conditions in the Kursk district of the Stavropol Territory on the farm of “StavAgroCom” on southern carbonate chernozem. As a modifier of mineral fertilizers, one of the most common synthetic polymers, polyvinyl alcohol (PVA), was used. The polymer consumption rate was 3, 5 and 7 kg per 1 ton of fertilizer. Yield growth was positively correlated with the dose of polymer in the fertilizer. The analysis of soil properties was carried out by the method of principal components. The resulting clustering in the coordinates of the first two components (in total they explain 65% of the data variation) shows significant differences in soil properties under different experimental options. To assess the efficiency of the use of nutrients depending on the dose of the polymer, a differential indicator was proposed – the additional efficiency of the use of nutrients (E). It was estimated from the increase in yield relative to the zero dose of the polymer per unit reduction in the concentration of this element in the soil according to the proposed formula. It is shown that the polymer use in fertilizer gives a statistically significant increase in the efficiency of phosphorus and potassium use by winter wheat.

The effect of a superabsorbent as a soil amendment on seed yield and chemical composition of two soybean genotypes

ABSTRACT In the era of observed climatic changes that contribute to the emergence of soil moisture deficiency, effective ways to retain and rationally manage water are being sought. One of the ways to make water available during periods without rain is the use of a superabsorbent. The aim of the study was to identify the response of two soybean cultivars (Glycine max (L.) Merrill) to different doses of a superabsorbent polymer (SAP). The effect of the SAP on seed yields, selected elements of the yield structure and the chemical composition of seeds were evaluated. The study was carried out during 2016–2018, based on a two-factor field experiment, in a split-plot design, where the dose of SAP (0, 20, 30 kgha−1) and legume cultivar (Aldana, Merlin) were the factors. The results of the research showed that SAP application significantly increased the yield of soybean, but did not affect the quantitative traits and chemical composition of seeds. Genetic factors differentiated the seed yields and chemical composition of the soybeans. A significantly higher yield was obtained for the Merlin cultivar compared to Aldana (by 31.0% on average). The Merlin cultivar accumulated more total protein in seeds, but contained significantly less crude ash and potassium compared to Aldana.

PVA/TS-1 composite embedded thin-film nanocomposite reverse osmosis membrane with enhanced desalination performance and fouling resistance

Thin-film nanocomposite reverse osmosis (TFN-RO) membranes were fabricated in this study. Titanium silicate-1 (TS-1) was used as an additive during interfacial polymerization. Since nanoparticle dispersion in the membrane matrix is a significant challenge in fabricating high-performance membranes, polyvinyl alcohol/titanium silicate-1 (PVA/TS-1) composite with different PVA polymer dosage was prepared and used in TFN-RO membrane to provide better dispersion of the synthesized TS-1. As a result, the pure water flux increased by 39.5%, and the NaCl rejection improved from 95.03% to 99.1% at the optimum content of 0.1 wt.% (PVA) and 0.1 wt.% (TS-1). The antifouling properties of this membrane for bovine albumin serum (BSA) and humic acid (HA) were enhanced. Characterization of the morphologies of the membranes was investigated using AFM and FESEM. The measurement of water contact angle and zeta potential was accomplished to characterize the surface properties of the membranes. ATR-FTIR was used to study the chemical structure of the membranes. Following the introduction of the PVA/TS-1 composite, the TFN membranes became smoother, thinner, more hydrophilic, and negatively charged. Due to hydroxyl groups and less cross-linked structure of the top layer, water flux was higher. A smoother surface and more negative charges on the top layer also improved fouling resistance.