Dodecylbenzenesulfonate Research Articles

Study of the Effect of the Surfactant Linear Alkylbenzene Sulfonate (LAS) on the Coagulation of Aged Microplastic

Objective: Evaluate the effect of linear alkylbenzene sulfonate (LAS) surfactant on the coagulation of aged microplastic. Theoretical Framework: Chemical coagulation is one of the steps adopted in water treatment that can help remove microplastics. During coagulation, suspended particles agglomerate, increasing the efficiency of removing these particles in the sedimentation stage. However, when coagulation occurs in the presence of surfactants, evidence points to deficits in removal capacity. Method: Using Jar Test tests, the optimal parameters for microplastic removal were determined with aluminum sulfate as a coagulating agent in the presence and absence of the surfactant linear alkyl benzene sulfonate (LAS). The LAS concentrations studied were in the range of 20 mg/L to 300 mg/L. Microplastic removal efficiency was evaluated by measuring turbidity. Results and Discussions: The combination of pH and coagulant concentration values that best suited the system were 5.0 and 4.25 mg/L, respectively. Due to the addition of surfactants, a decrease in removal efficiency was observed, with an average value ranging from 94.79% to 76.50% due to the interaction of polyethylene spheres with the surfactant. Research Implications: As explained, due to the coexistence of microplastics and surfactants in the aqueous environment, studies that describe chemical coagulation under these conditions have great value for optimizing treatment systems and technologies. Research Originality/Value: The use of aged microplastics aims to approximate their natural occurrence.

Preparation of polyaniline conductive membranes through immersion of dopant solution for dye/salt separation

The preparation of conductive loose nanofiltration (NF) membranes for effective separation of dye/salt wastewater mixtures remains a great challenge. In the current study, a novel method of immersing the polyaniline (PANI) membrane in some organic salt solutions to dope PANI membrane was employed to prepare conductive PANI loose NF membranes. Three dopants with different molecular weight, poly (sodium 4-styrene sulfonate) (PSS), sodium dodecyl sulfate (SDS), and sodium dodecylbenzene sulfonate (SDBS), were chosen to prepare the doping solutions under neutral and acidic (pH = 0.5 in HCl) conditions. The neutrally doped PANI membranes all had lower pore size distribution, lower Zeta potential, and higher conductivity compared with the undoped PANI membrane; and these properties were further enhanced for the membranes doped under acidic condition. The PANI membrane doped by acidic PSS solution (PANI-PSS-HCl membrane) had a pore size of 1.7 nm and a pure water flux of 44.7 L·m−2·h−1, and exhibited a rejection of over 99.9 % for eriochrome black T, acid fuchsin, congo red, and sunset yellow in the dye solutions, whereas less than 5 % for NaCl solution, which was suitable for dye/salt separation due to the large molecular size of PSS. When PANI-PSS-HCl membrane was used as the cathode, the membrane exhibited excellent anti-fouling performance with increased external voltage due to enhancement of electrostatic repulsion force between the anionic dyes and the surface of the conductive membrane. This work provides a simple and reliable method to prepare conductive loose NF membranes for effective separation of dye/salt wastewater with excellent anti-fouling performance under external voltage.

Preparation and characterization of high-performance water-based graphene dispersions for conductive coating on textiles

Studies on e-textile applications have gained momentum with advanced material technologies. Graphene derivatives have become the focus of e-textile advanced studies due to their high conductivity potential. The chemical selection while preparing graphene dispersions to functionalize textiles affects the dispersion quality and integration into the fabric. In this study, water-based green graphene dispersions were prepared using sodium dodecyl benzene sulfonate (SDBS) as a surfactant and polyvinyl alcohol (PVA) as a binder due to its high solubility in water. The stability of graphene nanoplatelets (GNP), GNP/SDBS and GNP/SDBS/PVA dispersions were examined with the naked eye at certain time intervals. UV–vis spectroscopy results indicated that SDBS provided better dispersion and stability of graphene. The XPS results showed a strong interaction between GNP and SDBS, while the binding of PVA and SDBS in the dispersion was supported by FTIR results. Overall, the dispersion quality of water-based graphene dispersion was enhanced using PVA and SDBS for e-textile application. The electrical conductivity and tensile strength of the graphene-coated fabrics increased up to ∼1.6 (MΩ/☐) and 388%, respectively, in compared to the intact fabric.

Use of nitrate, sulphate, and iron (III) as electron acceptors to improve the anaerobic degradation of linear alkylbenzene sulfonate: effects on removal potential and microbiota diversification.

Linear alkylbenzene sulfonate (LAS) is a synthetic anionic surfactant that is found in certain amounts in wastewaters and even in water bodies, despite its known biodegradability. This study aimed to assess the influence of nitrate, sulphate, and iron (III) on LAS anaerobic degradation and biomass microbial diversity. Batch reactors were inoculated with anaerobic biomass, nutrients, LAS (20mg L-1), one of the three electron acceptors, and ethanol (40mg L-1) as a co-substrate. The control treatments, with and without co-substrate, showed limited LAS biodegradation efficiencies of 10 ± 2% and 0%, respectively. However, when nitrate and iron (III) were present without co-substrate, biodegradation efficiencies of 53 ± 4% and 75 ± 3% were achieved, respectively, which were the highest levels observed. Clostridium spp. was prominent in all treatments, while Alkaliphilus spp. and Bacillus spp. thrived in the presence of iron, which had the most significant effect on LAS biodegradation. Those microorganisms were identified as crucial in affecting the LAS anaerobic degradation. The experiments revealed that the presence of electron acceptors fostered the development of a more specialised microbiota, especially those involved in the LAS biodegradation. A mutual interaction between the processes of degradation and adsorption was also shown.

Identification of new endocrine disruptive transthyretin ligands in polluted waters using pull-down assay coupled to non-target mass spectrometry

Surface and treated wastewater are contaminated with highly complex mixtures of micropollutants, which may cause numerous adverse effects, often mediated by endocrine disruption. However, there is limited knowledge regarding some important modes of action, such as interference with thyroid hormone (TH) regulation, and the compounds driving these effects. This study describes an effective approach for the identification of compounds with the potential to bind to transthyretin (TTR; protein distributing TH to target tissues), based on their specific separation in a pull-down assay followed by non-target analysis (NTA). The method was optimized with known TTR ligands and applied to complex water samples. The specific separation of TTR ligands provided a substantial reduction of chromatographic features from the original samples. The applied NTA workflow resulted in the identification of 34 structures. Twelve compounds with available standards were quantified in the original extracts and their TH-displacement potency was confirmed. Eleven compounds were discovered as TTR binders for the first time and linear alkylbenzene sulfonates (LAS) were highlighted as contaminants of concern. Pull-down assay combined with NTA proved to be a well-functioning approach for the identification of unknown bioactive compounds in complex mixtures with great application potential across various biological targets and environmental compartments.

Surfactant-Enhanced Assisted Spontaneous Imbibition for Enhancing Oil Recovery in Tight Oil Reservoirs: Experimental Investigation of Surfactant Types, Concentrations, and Temperature Impact

Surfactant-assisted spontaneous imbibition is an important mechanism in enhanced oil recovery by capillary pressure in low permeability and tight oil reservoirs. Though many experiments have been conducted to study the mechanism of enhanced oil recovery by surfactant-assisted spontaneous imbibition, the effects of surfactant type, concentration, and temperature have not been well studied. Using tight sandstone outcrop core samples with similar permeability and porosity, this paper experimentally studies surfactant-assisted spontaneous imbibition using three different surfactant types, i.e., sodium dodecylbenzene sulfonate (SDBS), cocamidopropyl betaine (CAB), and C12–14 fatty alcohol glycoside (APG). In addition to the type of surfactant, the effect of the surfactant concentration and the temperature is also investigated. The study results show that the ultimate oil recovery of spontaneous imbibition with formation water and denoised water is about 10%. Surfactant can significantly improve the oil recovery of spontaneous imbibition by reducing the interfacial tension between oil and water, emulsifying crude oil and improving oil mobility. APG showed better performance compared to SDBS and CAB, with a maximum oil recovery factor of 36.19% achieved with formation water containing 0.05% APG surfactant. Lower concentrations (0.05% APG) in the formation water resulted in a higher oil recovery factor compared to 0.1% APG. Increasing temperature also improves oil recovery by reducing oil viscosity. This empirical study contributes to a better understanding of the mechanism of surfactant-assisted spontaneous imbibition and enhanced oil recovery in tight oil reservoirs.

Comparative Analysis of Hydrogel Adsorption/Desorption with and without Surfactants.

In this particular study, a hydrogel known as SAP-1 was synthesized through the grafting of acrylic acid-co-acrylamide onto pullulan, resulting in the creation of Pul-g-Poly (acrylic acid-co-acrylamide). Additionally, a sponge hydrogel named SAP-2 was prepared by incorporating the surfactant sodium dodecyl benzene sulfonate (SDBS) into the hydrogel through free radical solution polymerization. To gain further insight into the composition and properties of the hydrogels, various techniques, such as Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (1H NMR), atomic absorption spectroscopy, and field emission scanning electron microscopy (FE-SEM), were employed. Conversely, the absorption kinetics and the equilibrium capacities of the prepared hydrogels were investigated and analyzed. The outcomes of the investigation indicated that each of the synthesized hydrogels exhibited considerable efficacy as adsorbents for cadmium (II), copper (II), and nickel (II) ions. In particular, SAP-2 gel displayed a remarkable cadmium (II) ion absorption ability, with a rate of 190.72 mg/g. Following closely, SAP-1 gel demonstrated the ability to absorb cadmium (II) ions at a rate of 146.9 mg/g and copper (II) ions at a rate of 154 mg/g. Notably, SAP-2 hydrogel demonstrated the ability to repeat the adsorption-desorption cycles three times for cadmium (II) ions, resulting in absorption capacities of 190.72 mg/g, 100.43 mg/g, and 19.64 mg/g for the first, second, and third cycles, respectively. Thus, based on the abovementioned results, it can be concluded that all the synthesized hydrogels possess promising potential as suitable candidates for the adsorption and desorption of cadmium (II), copper (II), and nickel (II) ions.

In-Situ AFM Studies of Surfactant Adsorption on Stainless Steel Surfaces during Electrochemical Polarization

Corrosion inhibitors are one of the best practices to prevent the far-reaching negative impacts of corrosion on ferrous alloys. A thorough understanding of their corrosion-inhibiting effects is essential for a sustainable economy and environment. Anionic surfactants are known to act efficiently as corrosion inhibitors. Here, we present that in-situ atomic force microscopy (AFM) measurements can provide deep insights into the adsorption and inhibition mechanism of surfactants on stainless steel surfaces during local corrosion. These include the configuration of surfactant molecules on the surface and how the microstructure of the stainless steel surface influences the inhibition process. Three different anionic surfactants, namely palm kernel oil (PKO), linear alkylbenzene sulfonate (LAS), and fatty alcohol ether sulfate (FAES), were investigated on a titanium-stabilized ferritic stainless steel (1.4510) in NaCl solution. For PKO, the results show random adsorption of bi- and multilayer whereas LAS and FAES adsorb only as local corrosion occurs. Thereby, LAS accumulates only locally and especially at the titanium precipitates of the 1.4510 and FAES forms a densely packed monolayer on the surface. This leads to better corrosion inhibiting properties for LAS and FAES compared to PKO.

Humic-like components in dissolved organic matter inhibit cadmium sequestration by sediment

China's lakes are plagued by cadmium (Cd) pollution. Dissolved organic matter (DOM) significantly regulates Cd(II) transport properties at the sediment-water interface. Understanding the effects of different DOM components on the transportation properties of Cd(II) at the sediment-water interface is essential. In this study, typical DOM from different sources was selected to study Cd(II) mobility at the sediment-water interface. Results showed that terrestrial-derived DOM (fulvic acids, FA) and autochthonous-derived DOM (α-amylase, B1) inhibit Cd(II) sequestration by sediments (42.5% and 5.8%, respectively), while anthropogenic-derived DOM (sodium dodecyl benzene sulfonate, SDBS) increased the Cd(II) adsorption capacity by sediments by 2.8%. Fluorescence quenching coupling with parallel factor analysis (EEM-PARAFAC) was used to characterize different DOM components. The results showed that FA contains three kinds of components (C1, C3: protein-like components, C2: humic-like components); SDBS contains two kinds of components (C1, C2: protein-like components); B1 contains three kinds of components (C1, C2: protein-like components, C3: humic-like components).Three complex reaction models were used to characterize the ability of Cd(II) complex with DOM, and it was found that the humic-like component could hardly be complex with Cd(II). Accordingly, humic-like components compete for Cd(II) adsorption sites on the sediment surface and inhibit Cd(II) adsorption from sediments. Fourier transform infrared spectroscopy (FTIR) of the sediment surface before and after Cd(II) addition was analyzed and proved the competitive adsorption theory. This study provides a better understanding of the Cd(II) mobilization behavior at the sediment-water interface and indicates that the input of humic-like DOM will increase the bioavailability of Cd.

A Study of Water-Based Nanolubricants Using Hexagonal Boron Nitride (hBN)-Based Nanocomposites as Lubricant Additives

An Rtec ball-on-disk tribometer was used to investigate the tribological performance of the synthesised water-based nanolubricants containing hBN/TiO2 nanocomposite at room temperature. The water-based nanolubricants with different concentrations were prepared by adding glycerol and sodium dodecyl benzene sulfonate (SDBS) under ultrasonication. These as-prepared nanolubricants demonstrated exceptional dispersion stability for 7 days without distinct sedimentation. The results indicate that the water-based nanolubricants with an overall concentration of 1.0 wt% at different ratios (hBN: TiO2 = (1:0), (0.7:0.3), (0.5:0.5), (0.3:0.7), (0:1)) can effectively reduce the coefficient of friction (COF) and the wear of the ball and disk. In particular, the water-based nanolubricant containing 0.5 wt% hBN and 0.5 wt% TiO2 exhibited the best tribological performance, leading to a significant reduction in COF up to 70%, and decreased the wear area of the ball and disk by up to 79.57% and 60.40%, respectively, compared to those obtained using distilled water. The lubrication mechanisms were mainly attributed to the formation of a protective film, and the mending, polishing, rolling, and synergistic effects of the hBN nanosheets and TiO2 nanoparticles.

DBS−-doped polypyrrole/CNTs with 3D conductive architecture connected with MoS2 as symmetrical electrodes for boosted CDI capability

Molybdenum disulfide (MoS2), as an appealing Faradaic material for efficient capacitive deionization (CDI), is limited by unsatisfactory electrical conductivity, inferior removal rate, and restacking. Herein, we develop a CNT/PPy/MoS2 ternary composite using a robust 3D conductive interconnected structure CNT/PPy, constructed from multi-walled carbon nanotubes (MWCNTs) and polypyrrole (PPy) doped with dodecyl benzene sulfonate (DBS-), as the growing substrate to mitigate the aggregation of MoS2 nanoflakes. In this design, CNT/PPy ameliorates the wettability of the composite, provides convenient movement pathways, a fast charge transport rate, and facilitates ions diffusion process. Moreover, reinforced dispersibility and enlarged interlayer spacing of MoS2 nanoflakes supply sufficient embedded sites for ion uptake and rapid transfer. Meanwhile, tight chemical coupling of Mo-N-C bonds can maintain the structural integrity of the composite electrode. Particularly, the symmetrical electrode configuration was established to address the kinetical unbalance of HCDI system. Consequently, the CNT/PPy/MoS2 displays a large specific capacitance of 160.83 F g−1 at 5 mV s−1, which is nearly 4.33 times that of MoS2 (37.17 F g−1). The optimized CNT/PPy/MoS2 cell achieves a maximum desalination capacity of 24.8 mg g−1, ultra-high deionization rate of 5.24 mg g−1 min−1, and superior capacity retention rate of 92.7% over 25 cycles. In addition, Na+ ions were captured by the joint action of cation-exchange of DBS--doped PPy, electrostatic adsorption of CNTs, and intercalation reaction of MoS2. The proposed composite structural design and electrode configuration should be a potential avenue to realize highly efficient deionization.

Growth and physiological responses of submerged macrophytes to linear alkylbenzene sulfonate (LAS)

The potential toxic effects of linear alkylbenzene sulfonate (LAS), widely used in commercial detergents and cleaners, on submerged macrophytes remain unclear. We conducted a two-week exposure experiment to investigate LAS toxicity on five submerged macrophytes (four native and one exotic), focusing on their growth and physiological responses. The results showed that lower concentrations of LAS (< 5 mg/L) slightly stimulated the growth of submerged macrophytes, while higher doses inhibited it. Increasing LAS concentration resulted in decreased chlorophyll content, increased MDA content and POD activity, and initially increased SOD and CAT activities before declining. Moreover, Elodea nuttallii required a higher effective concentration for growth compared to native macrophytes. These findings suggest that different species of submerged macrophytes exhibited specific responses to LAS, with high doses (exceeding 5 ∼ 10 mg/L) inhibited plant growth and physiology. However, LAS may promote the dominance of surfactant-tolerant exotic submerged macrophytes in polluted aquatic environments.

Metabolomics of cerebrospinal fluid reveals candidate diagnostic biomarkers to distinguish between spinal muscular atrophy type II and type III.

Classification of spinal muscular atrophy (SMA) is associated with the clinical prognosis; however, objective classification markers are scarce. This study aimed to identify metabolic markers in the cerebrospinal fluid (CSF) of children with SMA types II and III. CSF samples were collected from 40 patients with SMA (27 with type II and 13 with type III) and analyzed for metabolites. We identified 135 metabolites associated with SMA types II and III. These were associated with lysine degradation and arginine, proline, and tyrosine metabolism. We identified seven metabolites associated with the Hammersmith Functional Motor Scale: 4-chlorophenylacetic acid, adb-chminaca,(+/-)-, dodecyl benzenesulfonic acid, norethindrone acetate, 4-(undecan-5-yl) benzene-1-sulfonic acid, dihydromaleimide beta-d-glucoside, and cinobufagin. Potential typing biomarkers, N-cyclohexylformamide, cinobufagin, cotinine glucuronide, N-myristoyl arginine, 4-chlorophenylacetic acid, geranic acid, 4-(undecan-5-yl) benzene, and 7,8-diamino pelargonate, showed good predictive performance. Among these, N-myristoyl arginine was unaffected by the gene phenotype. This study identified metabolic markers are promising candidate prognostic factors for SMA. We also identified the metabolic pathways associated with the severity of SMA. These assessments can help predict the outcomes of screening SMA classification biomarkers.

Potential of Moringa oleifera saponins as a preventive of water pollution from the linear compound alkylbenzene sulfonate (LAS)

Potential of Moringa oleifera saponins as a preventive of water pollution from the linear compound alkylbenzene sulfonate (LAS)

Biological and Synthetic Surfactants Increase Class I Integron Prevalence in Ex Situ Biofilms.

The role of biocides in the spread of antimicrobial resistance (AMR) has been addressed but only a few studies focus on the impact of surfactants on microbial diversity and AMR, although they are common constituents of cleaners, disinfectants, and personal care products and are thus released into the environment in large quantities. In this study, we used a static ex situ biofilm model to examine the development of four biofilms exposed to surfactants and analyzed the biofilms for their prevalence of class I integrons as a proxy for the overall abundance of AMR in a sample. We furthermore determined the shift in bacterial community composition by high-resolution melt analysis and 16S ribosomal RNA (16S rRNA) gene sequencing. Depending on the initial intrinsic prevalence of class I integrons in the respective ex situ biofilm, benzalkonium chloride, alkylbenzene sulfonate, and cocamidopropyl betaine increased its prevalence by up to 6.5× on average. For fatty alcohol ethoxylate and the biosurfactants sophorolipid and rhamnolipid, the mean increase did not exceed 2.5-fold. Across all surfactants, the increase in class I integrons was accompanied by a shift in bacterial community composition. Especially benzalkonium chloride, cocamidopropyl betaine, and alkylbenzene sulfonate changed the communities, while fatty alcohol ethoxylate, sophorolipid, and rhamnolipid had a lower effect on the bacterial biofilm composition.

Flotation performance and mechanism of a novel collector for picromerite: Experimental and DFT study

Sodium dodecyl benzene sulfonate (SDBS) was developed to separate picromerite and halite as collector. The flotation tests showed that SDBS could separate picromerite from halite, the K+ recovery was 95.64 % and Na+ content was 1.42 % at SDBS dosage of 300 g/t. DFT calculations revealed that SDBS tended to adsorb on picromerite (-585.75 kJ/mol) than halite (-98.03 kJ/mol), and the selectivity of SDBS was better than SDS. Furthermore, SDBS chemically adsorbed on picromerite by the hybridization of O 2p within sulfonate and Mg 3 s of picromerite. This work further provides a reference for effectively separate picromerite and halite in industrial production.

Degradation of co-formulants and metabolites from plant protection products in courgette and tangerine using LC-HRMS: Laboratory tests

Plant protection products contain co-formulants that could end up in vegetables, and they can generate transformation products that can be more toxic than their original molecule, which are a potential risk to food safety. Therefore, this study evaluated the dissipation of two co-formulants, dodecylbenzenesulfonic acid and 1-ethyl-2-pyrrolidone, in courgette and tangerine samples to determine possible harmful metabolites under laboratory conditions. The analyses of these substances were performed by liquid chromatography coupled to quadrupole-Orbitrap high-resolution mass spectrometry (LC-Q-Orbitrap-HRMS). For the degradation of both compounds, a single-phase kinetic model was fitted, with R2 values greater than 0.99. In courgette and tangerine, half-lives (DT50) for dodecylbenzene sulfonic acid were 1.83 and 1.42 days, while DT50 was 6.26 and 5.04 days for 1-ethyl-2-pyrrolidone, respectively. Three metabolites of dodecylbenzenesulfonic acid and five metabolites of 1-ethyl-2-pyrrolidone were found in courgette, while the same metabolites were detected in tangerine samples, except benzoic acid and 4-aminobutanoic acid. These metabolites were identified for the first time from these compounds except for benzoic acid, observing that 5-hydroxy-N-ethylpyrrolidone was the most concentrated metabolite in tangerine 14 days after application, reaching a maximum concentration of 149 µg/kg. Furthermore, some of the detected metabolites possessed a value of LD50 lower than their original molecules. In consequence, such metabolites, derived from these co-formulants, should be controlled to prevent negative health effects, and ensure food safety.

Biological responses in Danio rerio by the disinfectant SDBS in SARS-CoV-2 pandemic

The use of disinfectants, such as Sodium Dodecylbenzene Sulfonic acid salt (SDBS), has grown since the SARS-CoV-2 pandemic, with environmentally unknown consequences. The present study analyzed SDBS effects in the fish species Danio rerio, using a combination of biomarkers. Our data reported that larvae had their total locomotor activity increased when exposed to 1 mg/L of SDBS, but this parameter was decreased in fish exposed to 5 mg/L. A significant increment of erratic movements was reported in fish exposed to 1 and 5 mg/L of SDBS. These concentrations inhibited CYP1A1/CYP1A2, and of GSTs inhibition, suggesting SDBS is not preferentially biotransformed by these routes. Results concerning the antioxidant defense biomarkers (CAT and GPx) showed no straightforward pattern, suggesting SDBS exposure may have resulted in changes in redox balance. Finally, acetylcholinesterase activity increased. In summary, increased use of SDBS in a near future may result in deleterious effects in environmentally exposed fish.

Stabilization of heavy metals in solid waste and sludge pyrolysis by intercalation-exfoliation modified vermiculite

Increasing amounts of solid waste and sludge have created many environmental management problems. Pyrolysis can effectively reduce the volume of solid waste and sludge, but there is still the problem of heavy metal contamination, which limits the application of pyrolysis in environmental management. The intercalated-exfoliated modified vermiculite (IEMV) by intercalators of sodium dodecylbenzene sulfonate, hexadecyltrimethylammonium bromide and octadecyltrimethylammonium bromide were used to control the release of Cd, Cr, Cu, Zn and Pb during pyrolysis process of sludge or solid waste. The retention of heavy metals in sludge was generally better than that in solid waste. The IEMV by octadecyltrimethylammonium bromide as the intercalator calcined 800 °C (STAB-800) was the best additive for heavy metal retention, and the retention of Cr, Cu and Zn was significantly better than that of Pb and Cd. Cr, Cu, Zn and Pb were at low risk, while Cd had considerable risk under certain circumstances. New models were proposed to comprehensively evaluate the results of the risk and forms of heavy metals, and the increasing temperature was beneficial in reducing the hazards of heavy metals by the addition of STAB-800. The reaction mechanism of heavy metals with vermiculite was revealed by simulation of reaction sites, Fukui Function and Frontier Molecular Orbital. Thermal activation-intercalated-exfoliated modified vermiculite (T-IEMV) is more reactive and had more active sites for heavy metals. Mg atoms and outermost O atoms are the main atoms for T-IEMV to react with heavy metals. The Cr, Cu and Zn have better adsorption capacity by T-IEMV than Pb and Cd. This study provides a new insight into managing solid waste and sludge and controlling heavy metal environmental pollution.

Mutual role of dodecylbenzene sulfonic acid on enhanced oil recovery and asphaltene inhibition in low salinity medium: Experimental and XDLVO study

Understanding the molecular interactions during oil recovery processes can shed light on screening new chemicals for future operations. Of particular interest are chemicals capable of providing the mutual role of asphaltene inhibition and interfacial tension reduction at liquid–liquid and rock-liquid interfaces. This study delves into the interfacial interactions between low-salinity brines, model oils containing dodecylbenzene sulfonic acid, and dolomite rock surfaces. In the experimental part, the asphaltene precipitation inhibition efficacy of dodecylbenzene sulfonic acid was evaluated through filtration and precipitation test, and its oil recovery performance was examined from interfacial tension reduction and wettability alteration viewpoints. The theoretical part was then followed by the implementation of the surface energy concept based on the XDLVO theory, where acid-base and Lifshitz-van der Waals interaction energies, as well as the work of cohesion/adhesion between interacting bodies in asphaltene and oil recovery systems, were considered. The results obtained from this study revealed that dodecylbenzene sulfonic acid, owing to its acidic nature and the long alkyl chain in its structure, could simultaneously perform the role of asphaltene inhibitor and oil recovery agents. In particular, asphaltene particles showed less tendency to aggregate and form macrostructures in the presence of low-salinity brines formulated with magnesium chloride. The total interaction energy between asphaltene particles was almost halved by the addition of dodecylbenzene sulfonic acid. The low interfacial tension of 0.16 mN/m between model oil containing 1 wt% of DBSA and low-salinity brine containing 5000 mg/L magnesium chloride and the wettability alteration of the dolomite sample toward water-wetness were also confirmed by theoretical calculations using the concept of work of adhesion.