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MoS 2 /montmorillonite (MoS 2 /Mt) composite was successfully synthesized through a simple hydrothermal method, and its adsorption performance for two emerging contaminants-atenolol (ATE) and acebutolol (ACE) was researched. The batch experiments revealed that the adsorption process can be described by the Pseudo-second order model and Langmuir model, and the adsorption capacity of MoS 2 /Mt, MoS 2 and Mt for ATE were 132.08 mg/g, 60.68 mg/g and 74.23 mg/g, for ACE were 113.82 mg/g, 33.01 mg/g and 36.05 mg/g, respectively. Besides, Fourier-transform infrared spectroscopy (FTIR), BET specific surface area measurement and X-ray photoelectron spectroscopy (XPS) were also employed to analyze the adsorption mechanism. Moreover, quantitative molecular surface analysis and weak intermolecular interaction analysis with independent gradient model were combined to probe the microscopic interaction between the adsorbent and adsorbate. The results indicated the interactions included hydrogen bonding and vdW interaction. Mt and MoS 2 interacted more strongly with ATE than ACE, which revealed the reason MoS 2 /Mt, Mt and MoS 2 possessed higher adsorption capacity for ATE. [Display omitted] • MoS 2 /Mt composite was successfully synthesized. • Compared with MoS 2 and MT, MoS 2 /Mt has better adsorption capacity for ATE and ACE. • Adsorption capacity of MoS 2 /Mt composite for ATE is larger than that for ACE. • The adsorption of ATE and ACE on MoS 2 /Mt was fitted to the Langmuir model. • Interactions of MoS 2 /Mt with ATE or ACE include hydrogen bonding and vdW interaction. [ABSTRACT FROM AUTHOR]

An eco-friendly corncob biochar based montmorillonite composite (Cc-Mt) was synthesized for the single adsorption and co-adsorption of lead (Pb(II)) and a pharmaceutical emerging organic contaminant Atenolol (ATE). In single adsorption system, the maximum equilibrium capacity of Cc-Mt for Pb (II) and ATE were 139.78 mg g−1 and 86.86 mg g−1, respectively, but for montmorillonite just 98.69 mg g−1 and 69.68 mg g−1, for corncob biochar just 117.54 mg g−1 and 47.29 mg g−1. Meanwhile,co-adsorption properties of ATE and Pb(II) on Cc-Mt composite were performed and found that the influence of ATE on the adsorption of Pb(II) was greater than the effect of Pb(II) on that of ATE. Moreover, Multiwfn program based on quantum chemical calculation was used to quantitatively analyze electrostatic potential (ESP) distribution, average local ionization energy (ALIE) distribution and their minimum points on neutral ATE and protonated ATE (PATE) molecules to reveal the microscopic adsorption mechanism of Cc-Mt composite to ATE, the results showed that the amino N and amide oxygen atom were easier to provide lone pair of electrons, generating hydrogen bonds or strong electrostatic interactions with functional groups on the surface of Cc-Mt, meanwhile hydroxyl O atom was also a possible reaction site. For PATE molecules, only the oxygen atom of the amide group was the most likely reactive site. Image 1 • Synthesized biochar-montmorillonite composite showed high absorption efficiency of Pb(II) and β-blocker (atenolol). • Coadsorption characteristic of Pb(II) and atenolol onto biochar-montmorillonite composite was studied. • Multiwfn program based on quantum chemical calculation was used to reveal the microscopic adsorption mechanism. [ABSTRACT FROM AUTHOR]

The novel environment-friendly hexadecanoamide propyltrimethy lammonium chloride (NQAS16-3) surfactant with different amounts (0.2, 0.4, 0.6, 0.8, 1.0, 1.2 CEC) was firstly used to modify montmorillonite, and the obtained organomontmorillonite (N-Mt) with the amount of surfactant equal to 1.0 CEC was utilized to adsorb two β-blocker pollutants- Atenolol (ATE) and acebutolol (ACE). The experimental results indicated that the equilibrium adsorption capacity of N-Mt(the organo-montmorillonite that the amount of modifier was 1.0 CEC) for ATE and ACE was 93.47 mg/g and 84.55 mg/g, respectively, which was more than twice that of raw montmorillonite for two pollutants, the adsorption was better fitted with the pseudo-second-order model and Langmuir isotherms model, and the adsorption was the spontaneous and exothermic process. Moreover, combining with the Zeta potential values of N-Mt, and with the help of Multiwfn wave function program based on density functional theory (DFT), the electrostatic interaction and the hydrophobic partitioning between N-Mt and two pollutant molecules were verified, p-π/π interaction between NQAS16-3 and ATE (or ACE) may be contributed to the increasing adsorption capacity of N-Mt for two β-blocker pollutants. The work provided novel organomontmorillonite for the removal of non-degradable β-blocker pollutants and the insight of the adsorption mechanism from the atomic level. [ABSTRACT FROM AUTHOR]

• Protonated graphite carbon nitride and acid activated montmorillonite (g-C 3 N 4 /Mt). • Batch experiments carried out at various conditions i.e. adsorbate concentration, pH, temperature, and contact time. • 2%-g-C3N4/Mt showed enhanced adsorption capacity for PO 4 3− and Pb(II), 5.06 mg/g and 182.7 mg/g respectively. • The adsorption process for both contaminants showed well-fitting with the pseudo-second-order kinetic model. • The thermodynamic study suggested that the adsorption of Pb(II) was a spontaneous and endothermic process. A novel protonated graphite carbon nitride and acid-activated montmorillonite (g-C 3 N 4 /Mt) composite was prepared and evaluated its removal efficiency for PO 4 3− and Pb(II) from aqueous media. The as-prepared composite was characterized by XRD, FT-IR, TG, XPS, SEM, BET and Zeta potential. Batch experiments were carried out under various conditions such as the amount of adsorbent, initial adsorbate concentration (C o), solution pH, temperature, and contact time. 2.0%-g-C 3 N 4 /Mt presented maximum adsorption capacity for PO 4 3− and Pb(II) as compared to single g-C 3 N 4 , Mt or other synthesized composites. The removal efficiency of the as-prepared composite (2.0%-g-C 3 N 4 /Mt) was significantly elevated owing to the synergistic effects and the saturated adsorption capacities of PO 4 3− and Pb(II) on 2%-g-C3N4/Mt was 5.06 mg/g and 182.7 mg/g respectively. While the saturated adsorption capacity of bare g-C 3 N 4 was only 1.56 mg/g and 22.3 mg/g for PO 4 3− and Pb(II) respectively, and bare Mt showed adsorption capacity of 0.65 mg/g and 124.2 mg/g for PO 4 3− and Pb(II) respectively. The adsorption process for both contaminants showed well-fitting with the pseudo-second-order kinetic model, and the adsorption isotherm for both contaminants followed the Langmuir model. The thermodynamic study suggested that the adsorption of Pb(II) was a spontaneous and endothermic process. [ABSTRACT FROM AUTHOR]

Sodium lignosulfonate (Na-LS) was used to modified montmorillonite to form lignosulfonate-montmorillonite (LS-MMT). The as-prepared samples were characterized by various equipment to analyze the surface morphology and structure of the pure and reformed samples. The adsorption capability (q e , mg/g) of LS-MMT or Ca/Na-MMT for Pb(II) and Cu(II) at different reaction intervals, the concentration of metal ions, temperature, and pH were studied by batch adsorption experiments. The results revealed that LS-MMT displayed a higher adsorption capacity than Ca/Na-MMT. The pH of solutions had a great influence on the q e of the two adsorbents, and the q e was slightly enhanced with temperature increasing. The isotherm and kinetic experiments studies indicated that the adsorption of heavy metal on LS-MMT or Ca/Na-MMT fit well with the Langmuir model and pseudo-second-order kinetic model. The competitive adsorption showed that LS-MMT had a stronger affinity for Pb(II) than Cu(II), which was different from Ca/Na-MMT. Additionally, the desorption experiment showed that LS-MMT had a stronger ability to lock heavy metal ions than Ca/Na-MMT in an acidic environment with pH ranging from 3 to 5. Unlabelled Image • Lignin is a non-toxic natural polymer comprising many functional groups, i.e. carboxy, phenol, hydroxyl and methoxy groups. • The results revealed that LS-MMT displayed a higher adsorption capacity than Ca/Na-MMT. • The isotherm and kinetic experiments fit well with the Langmuir model and pseudo-second-order kinetic model. • The competitive adsorption showed that LS-MMT had a stronger affinity to Pb(II) than Cu(II). • LS-MMT had a stronger ability to lock heavy metal ions in an acidic environment with a pH range from 3 to 5. [ABSTRACT FROM AUTHOR]