Effects of interfacial tension, oil layer break time, emulsification and wettability alteration on oil recovery for carbonate reservoirs

Formulation and Optimization of Effective Oil Spill Dispersants Composed of Surface-Active Ionic Liquids and Nonionic Surfactants

The use of chemical dispersants to remove oil spills in aquatic environments raises serious concerns, including heightened toxicity and limited biodegradability, which diminish their effectiveness. This study aimed to develop an environmentally friendly formulation by combining two nonionic surfactants (Tween 80, Span 80) with two surface-active ionic liquids (SAILs): 1-butyl-3-methylimidazolium lauroyl sarcosinate [Bmim][Lausar] and choline myristate [Cho][Mys], to remediate crude oil spill. The performance of the formulation was evaluated by its emulsion stability, surface tension, interfacial tension (IFT), and effectiveness. The toxicity and biodegradability of the formulation were also assessed to ensure their safe application in aquatic environments. The formulation (F9) exhibited the most stable emulsion, maintaining stability even after 5 h with a critical micelle concentration (CMC) of 3.52 mM. The efficiency of the formulation in dispersing various crude oils (Arab, Ratawi, and Doba) ranged from 70.12 to 93.72%. Acute toxicity tests conducted on zebrafish demonstrated that the formulation, with an LC50 value of 450 mg L-1, exhibited practically nontoxicity after 96 h. The formulation showed rapid biodegradability, exceeding 60% within a 28-day testing period. This research presents a promising approach for synthesizing the green formulation which can contribute to mitigating the environmental impacts of oil spills and enhancing the efficiency of cleanup operations.

Microwave-Assisted Sol-Gel Preparation of the Nanostructured Magnetic System for Solid-Phase Synthesis

This work describes a new synthesis method for core–shell magnetite nanoparticles with a secondary silica shell, functionalized with a linker system (Fe₃O₄-PABA-SiO₂-linker) using a microwave-assisted heating technique. The functionalized solid nanomaterial was used for the nanophase synthesis of peptides (Fmoc route) as a solid support. The co-precipitation method was selected to obtain magnetite nanoparticles and sol–gel technique for silica coating using a microwave-assisted (MW) procedure. The magnetic properties of the nanoparticle core offer the advantage of a quick and easy alternative for the magnetic separation of the product from the reaction mixture, facilitating all the intermediary washing and separation operations. The intermediate and final materials were analyzed by advanced characterization methods. The effectiveness of the nanophase peptide synthesis using this nanostructured material as solid support was demonstrated for a short peptide sequence.

Chasing the Critical Wetting Transition. An Effective Interface Potential Method

Wettablity is one of the important characteristics defining a given surface. Here we show that the effective interface potential method of determining the wetting temperature, originally proposed by MacDowell and Müller for the surfaces exhibiting the first order wetting transition, can also be used to estimate the wetting temperature of the second order (continuous) wetting transition. Some selected other methods of determination of the wetting temperature are also discussed.

Synthesis of cetyl trimethyl ammonium bromide (CTAB) capped copper oxide nanocubes for the remediation of organic pollutants using photocatalysis and catalysis

The aim of this report is to synthesize copper oxide nanocubes (CuO NCs) at room temperature, using sodium borohydride as a reducing agent, and Cetyl Trimethyl Ammonium Bromide (CTAB) as a stabilizing agent. The crystallinity and morphology of the synthesized CuO NCs are investigated via X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). The optical properties were analyzed by means of UV-visible absorbance and Raman spectroscopy. The existence of specific functional groups and structural stability were established via FTIR spectroscopy and thermogravimetric analysis (TGA). Furthermore, the catalytic efficiency of the as-prepared CuO NCs was tested using catalytic and photocatalytic studies of para-nitrophenol (p-NP) reduction and methylene blue (MB) degradation, respectively. The catalytic results demonstrated the nanocubes' excellent catalytic and photocatalytic responses with respect to the abatement of p-NP and MB within 50 s and 240 min, with kinetic rate constants of 3.9 × 10^-2 s^-1 and 6.47 × 10^-3 min^-1, respectively.