A model, including the chemical details of core nanoparticles as well as explicit surface charges and hydrophobic patches, of triblock Janus particles is employed to simulate nucleation and solid–solid phase transitions in two-dimensional layers. An explicit solvent and a substrate are included in the model, and hydrodynamic and many-body interactions were taken into account within many-body dissipative particle dynamics simulation. In order not to impose a mechanism a priori, we performed free (unbiased) simulations, leaving the system the freedom to choose its own pathways. In agreement with the experiment and previous biased simulations, a two-step mechanism for the nucleation of a kagome lattice from solution was detected. However, a distinct feature of the present unbiased versus biased simulations is that multiple nuclei emerge from the solution; upon their growth, the aligned and misaligned facets at the grain boundaries are introduced into the system. The liquid-like particles trapped between the neighboring nuclei connect them together. A mismatch in the symmetry planes of neighboring nuclei hinders the growth of less stable (smaller) nuclei. Unification of such nuclei at the grain boundaries of misaligned facets obeys a two-step mechanism: melting of the smaller nuclei, followed by subsequent nucleation of liquid-like particles at the interface of bigger neighboring nuclei. Besides, multiple postcritical nuclei are formed in the simulation box; the growth of some of which stops due to introduction of a strain in the system. Such an incomplete nucleation/growth mechanism is in complete agreement with the recent experiments. The solid–solid (hexagonal-to-kagome) phase transition, at weak superheatings, obeys a two-step mechanism: a slower step (formation of a liquid droplet), followed by a faster step (nucleation of kagome from the liquid droplet).

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The present research introduces adsorption of sulfonated cobalt phthalocyanine catalyst (Europhtal) from the real wastewater that is produced by the mercaptan removal unit (Merox) of the third refinery, South Pars Gas Complex (SPGC), Assaluyeh, Iran. Therefore, novel low-cost natural zeolite modified with polyaluminium chloride (PAC) was investigated as an adsorbent for the treatment of Europhtal wastewater. Central composite design (CCD), as a set of response surface methodology (RSM), was applied to acquire optimum operational conditions such as contact time, pH, adsorbent dosage, and Europhtal concentration. Results showed that the removal percentage of Europhtal in the real wastewater was 93.4% at best operating condition consisting of a pH of 6.7, sonication time of 8 min, 0.035 g of adsorbent. The obtained results were evaluated by adsorption isotherms and kinetic parameters. It was found that the equilibrium data matched the Freundlich model acceptably, with the maximum experimental adsorption capacity of this model was 687.51 mg g-1 at 301.15 K. From the kinetic data, it was revealed that the adsorption process followed the pseudo-second-order kinetic model. Furthermore, the obtained thermodynamic parameters such as ∆H°, ∆S°, and ∆G° imply the endothermic essence of adsorption proceeding spontaneously.

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