Wax deposition conveying crude oil is a severe issue because wax precipitates at low temperatures encountered during pipeline flow. Our research focuses on the development of new ionic liquids proved to be pour point depressants and flow improvers for Egyptian waxy crude oil. Three ILs were synthesized with high yield; about 86–88% and characterized using spectroscopic analytical techniques FT-IR and NMR (1H & 13C) to help in identifying and confirming their structures. Thermal stability and surface active properties were conducted and studied. The effectiveness of the ionic liquids were tested as pour point depressants and flow improvers showed encouraging set of data. Pour point reduction was determined according to ASTM D-97 and was noticed from 36 up to 24 °C with [BDPImi]+Br− and [BDPImi]+TFSI− suggesting significant improvement in the flowability of the treated waxy crude oil. The pour point depressants also induced reduction in the viscosities of treated crude oil. Rheological behavior (viscosity vs. shear rate), wax morphology (using optical microscopy), and aging stability (30-day storage) were illustrated. Quantum chemical calculations (DFT at B3LYP/6-31G (d,p)) provided electronic parameters (HOMO-LUMO gap, dipole moment, chemical hardness/softness) to rationalize the experimental findings. [BDPImi]+Br− and [BDPImi]+TFSI− demonstrated superior performance and reducing the pour point of WCO from 36 °C to 24 °C at minimum concentrations (250 ppm and 500 ppm, in order). Rheological studies at 35 °C exhibit viscosity reductions from 82.5 to 33.0 Pa·s (untreated) to 59.7–29.6 Pa·s and 14.2–10.1 Pa·s for [BDPImi]+Br− and [BDPImi]+TFSI− respectively. The aging effects resulting limiting pour point increase up to only 3 °C after 30 days against 6 °C for the origin oil. This experiment aims to create new PPD that are highly successful at ensuring the flow of waxy crude oil, which would be extremely useful for future research.

In this work, three asymmetric dicationic ionic liquids, namely, 1-(2-(1-decyl-1H-imidazolium-3-yl)ethyl)-4-methylpyridinium bromide (IL101), 1-(5-(1-decyl-1H-imidazolium-3-yl)pentyl)-4-methylpyridinium bromide (IL102), and 1-(10-(1-decyl-1H-imidazolium-3-yl)decyl)-4-methyl-pyridinium bromide (IL103) were synthesized. Their structures were confirmed and characterized via, elemental analysis, Fourier transform infra-red spectroscopy and proton nuclear magnetic resonance. The surface properties of these ionic liquids, surface tension, critical micelle concentration, effectiveness, maximum surface excess, and minimum surface area, were investigated with different concentrations at 25 & DEG;C. Standard free energies of micellization and adsorption were obtained. They were studied and tested as base oil improvers, especially oxidation stability, (through studying the change in total acid number [TAN] and viscosity), and foaming characteristics. The efficiency of these compounds as base oil improvers is ranked as follows, IL103 > IL102 > IL101.

This study synthesized three types of asymmetric dicationic ionic liquids, specifically, 1- ( 2 - (1- decyl - 1H - imidazolium - 3 - yl) ethyl) - 3 - methylpyridinium bromide (IL 201), 1- ( 5 - (1- decyl -1H - imidazolium - 3 - yl) pentyl) - 3 - methylpyridinium bromide (IL 202), and 1 - (10 - (1- decyl -1H -imidazolium -3 - yl) decyl) - 3 - methyl-pyridinium bromide (IL 203) and evaluated their structures via elemental analysis, FT- IR, and 1H - NMR spectroscopy also their surface activity, (surface tensions, critical micelle concentration, effectiveness, maximum surface excess and minimum surface area), were studied. Their influence on base oil was evaluated, including foaming characteristics and oxidation stability by studying the change in total acid number ‘TAN’ and viscosity. IL 203 was found to be the most efficient base oil improver, followed by IL 202 and IL 201.

Precipitation and deposition of asphaltene are considered as catastrophic issues facing the petroleum industry. Asphaltene deposition mainly occurs at variety places such as formation pore spaces, pumps, pipelines, wellbore, wellhead, tubing, surface facilities and safety valves causing operational problems, production deficiencies and enormous economic losses. This work aims to study the effect of series of synthesized aryl ionic liquids (ILs) containing different alkyl chains, named as R 8 -IL, R 10 -IL, R 12 -IL, and R 14 -IL, on the onset precipitation point of asphaltene in crude oil. R 8 -IL, R 10 -IL, R 12 -IL, and R 14 -IL were synthesized with high yields (the yield varied between 82 and 88%) and characterized via different tools of analysis (FTIR, 1 H NMR, and Elemental Analysis). Their Thermal Gravimetric Analysis (TGA) was investigated and showed a reasonable degree of stability. It was found that R 8 -IL (short alkyl chain) has the highest stability, while R 14 -IL (long alkyl chain) is the lowest one. Quantum chemical calculations were conducted to study the reactivity and geometry of their electronic structures. Moreover, surface and interfacial tension of them were studied. It was found that the efficiency of the surface active parameters increased by increasing the length of the alkyl chain. The ILs were evaluated to delay the onset precipitation point of asphaltene using to different methods; the kinematic viscosity and the refractive index. Results from the two methods showed delaying of onset precipitation after the addition of the prepared ILs. The asphaltene aggregates was dispersed due to the π–π* interactions and hydrogen bonds formation with the ILs.

The disastrous consequences for society—economically, environmentally, and socially—caused by oil spills encouraged us to treat this problem. The target of this work is to synthesize new amphiphilic dicationic ionic liquids (Ia, Ib, and Ic) and evaluate them spectroscopically and gravimetrically as potential oil spill dispersants at different temperatures to cover cold and warm areas. The synthesized ILs were well characterized by different tools for analysis of their surface activity and thermal stability. Ia, Ib, and Ic showed good dispersion effects, which were recorded to be 5.32, 20.45, and 33.61% for Ia, Ib, and Ic, respectively, at 10 °C and 12.28, 52.55, and 66.80% for Ia, Ib, and Ic, respectively, at 30 °C with a dispersant-to-oil ratio (DOR) of 0.8:10 (wt.%). Acute toxicity tests were elucidated against Nile tilapia and Oreochromis niloticus fish and confirmed their slight toxicity by determining a LC50 value greater than 100 ppm after 96 h, which recorded 13.25, 17.75, and 37.5 mg/L for Ia, Ib, and Ic, respectively. Overall, the new synthesized ILs can be represented as sustainable materials for toxic chemicals to disperse oil spills.

Organosilicon surfactants draw scientific attention due to their significant biological action as they offer the real possibility to improve their pharmacological properties because of easier penetration through lipophilic barriers inside the body. Synthesis, structure and spectroscopic characterization of cobalt (II), copper (II) and zinc (II) coordination compounds with N-dodecyl-N-trimethyl silane ammonium iodide are presented in this research. N-dodecyl-N-trimethyl silane ammonium iodide and its complexes with cobalt, copper and zinc chlorides were characterized structurally using Ultraviolet-Visible and Fourier Transform Infra-red spectra. Surface parameters of the prepared surfactants were investigated including, critical micelle concentration, maximum surface excess, minimum surface area, effectiveness, and efficiency. Free energy of micellization and adsorption were also calculated. The cytotoxic activity of various metallomicelle surfactants was tested against five lines of human tumor cells [ HEPG2 (liver), MCF-7 (breast), HCT-116 (colon), HEP2 (larynx), and HFB4 (normal)]. The results showed that zinc (II) and cobalt (II) complexes have substantial surface and cytotoxic activity whereas copper (II) complex showed less surface and cytotoxic activity.

Abstract During recent decades, focus has increased on biodiesel production from wastes or other nonedible resources. The high expense of the manufacturing process is one of the major obstacles it faces. So, continuous research for cheaper and safer resources is more important. Seed oil from various vegetables and fruit species has garnered a lot of: attention recently in the production of biodiesel, such as date palm. The date palm is. one of the most. popular fruits in the Middle East Egypt has recorded now as the highest countries production of dates. The oil of date seeds (DSO) has high concentrations of fatty acids and minerals. In biodiesel production, lipid extraction is an important step. But the advanced extraction techniques are preferred to protect human health and the environment. Therefore, the demand for innovative and environmentally friendly products is now necessary. Transesterification is the process in which oils (mostly triglycerides) bond with alcohol in the existence of a catalyst to form an alkyl ester. Synthesizing the green catalyst and utilizing it in the manufacture of biodiesel have a great added value. The high yield of biodiesel supports the catalyst suitability for the transesterification reaction. Immobilized lipase, moreover, plays a critical function in the transesterification process, that it is more effective and safer. DSO is being studied to see if its fatty acid profile or physicochemical properties suggest it could be a suitable biodiesel source.

Three asymmetric dicationic ionic liquids; 1-(2-(1-dodecyl-2-methyl-1H-imidazol-3-ium-3-yl)ethyl)-4-methylpyridin-1-ium bromide, 1-(6-(1-dodecyl-2-methyl-1H-imidazol-3-ium-3-yl)hexyl)-4-methylpyridin-1-ium bromide and 1-(10-(1-dodecyl-2-methyl-1H-imidazol-3-ium-3-yl) decyl)-4-methylpyridin-1-ium bromide (Ia, Ib &Ic respectively) were synthesized and characterized via Elemental analysis, FT-IR, 1H NMR, and Thermo-gravimetric analysis (TGA). Their surface activities were studied. The performance of the synthesized ionic liquids as oil spill dispersants were evaluated at different temperatures (10, 30 & 50 °C) and concentrations (750, 1500, 2000, 3000 ppm). Data reveals that the efficiency is ranked as follows: Ib > Ia > Ic with concentration of 1500 ppm.

Two series of well-defined dimeric metallo-bolaamphiphiles (bola surfactants) with the coordinated metal ions (Cu, Co, Zn) were prepared. These oligomeric surfactants consist of simple monomeric cationic surfactant fragments which are coupled via the hydrophilic ammonium chloride head groups by C-6 and C-12 spacer groups of different lengths. FTIR and (HNMR)-H-1 identification techniques confirmed the obtained products. Measurements of surface tensions showed that the synthesized Bola amphiphiles have the desired, relatively low critical micelle formation concentrations (CMC). Bola amphiphiles with long spacer groups (C-12) have a pronounced surface activity. The properties of these cationic surfactant oligomers in aqueous solution such as micellization and surface activity were discussed in relation to spacer group. In addition, the synthesized compounds were examined for their anti-microbial activity using the agar diffusion technique.

The adhesion of bacteria to solid surfaces depends on several factors, such as surface charge, surface energy, and the chemical composition of bacterial cell wall. The adhesion of bacterial cells to surfaces or within communities and subsequent biofilm formation are of great importance in several industrial and medical applications such as ship hulls, heat exchanger plates, food packaging materials, biomaterials implants, urinary catheters, contact lenses, and vascular grafts. Understanding the mechanism of adhesion of biomolecules and microorganisms to abiotic surfaces is important in developing means for its prevention. Bacterial attachment to solid surfaces in aqueous systems is a complex interaction between the bacterium, the solid substrate, and the liquid phase. Surface-associated microbial communities, called biofilms, are present in all environments. Although biofilms play an important positive role in a variety of ecosystems, they may also have negative impacts including biofilm-related infections in medical settings. The adhesion of bacteria to solid surfaces can be studied using physicochemical approaches based on van der Waal, electrostatic, and acid–base interactions. These methods provide important models of bacterial adhesion but have a limited capacity to provide a complete understanding of the complex adhesion process of real bacterial cells. In this chapter, we review the different types of microorganisms and their presence in the nature and also their adhesion on the different surfaces. The impacts of the different microorganisms on the tribological systems including metalworking fluids are discussed.

Three cationic gemini surface active compounds of the type (1r,4r)-1,4-dialkyl-1,4-dimethy-l-piperazine-1,4-diium bromide (Ia, Ib, and Ic), were synthesized. They were characterized using elemental analysis and H-1-NMR spectra. Their surface-active properties were measured in aqueous solutions with different concentrations at different temperatures (25, 40, and 55 degrees C). Various surface measurements of these gemini surfactants, (compared to the conventional one, 1-Dodecyl-1-methylpiperidinium bromide (a)) were estimated, specifically critical micelle concentration (CMC), effectiveness ((CMC)), efficiency (P-C20) as well as maximum surface excess ((max)) and minimum surface area (A(min)). The measurements of the gemini compounds gave low CMC, high efficiency in reducing the surface tension, and intense adsorption at air/water interface. These surfactants have lower Krafft points and thus better solubility. Thermodynamic data, free energy, entropy, and enthalpy changes (G degrees, S degrees, and H degrees) for micellization at the air/water interface and also for adsorption in the bulk of surface-active solutions were calculated. [GRAPHICS] .

Efficiencies of cationic gemini surfactant additives in improving the pour point depressant of crude oil were investigated. The length of alkyl chain is a major factor affecting the improvement of the pour point depression. The adsorption behavior of these gemini surfactants at air/solution and oil/solution interfaces were investigated by measuring the surface tension and interfacial tension as functions of concentration. It is found that there is a good relation between surface properties especially interfacial tension of the gemini surfactants and their efficiency in depressing the pour point. Also, the surface parameters and free energies of micellization and adsorption confirm the decreasing and improving of pour point depression. Crystallization study in crude oil revealed the relationship between the structure and activity of gemini surfactant additives. It is found that the x-ray diffraction patterns of waxes with additives are remarkably different from those without additives. The mechanism of the depressants action has been suggested according the adsorption of each additive. Adsorption of the additive on the surface of the wax particles inhibits their growth and alters the crystal habits through micelle core. Pretreatment of the crude oil with pour point depressants has received the greatest acceptance due to its simplicity and economy. [GRAPHICS] .

AbstractA series of N-alkyl pyridinium aldoxime surfactants was synthesized by the reaction of pyridinium aldoxime with long chain alkyl halides (decyl, dodecyl, tetradecyl and hexadecyl bromide). The chemical structure of the synthesized compounds was confirmed by elemental analysis and FTIR spectra. Surface tension was measured in aqueous solutions for different concentrations at 25 °C. Various surface properties of the synthesized surfactants were evaluated, particularly the critical micelle concentration (CMC), effectiveness (πCMC), efficiency (PC20) as well as the maximum surface excess (Γmax) and minimum surface area (Amin). Also, the micellization and adsorption at liquid/air interfaces were investigated. The synthesized cationic surfactants were evaluated for their biocidal activity. Good antibacterial and antifungal activities were recorded against Gram-positive bacteria (Bacillus subtilis ATCC 6633, Micrococcus luteus ATCC 25922), followed by Gram-negative bacteria (Escherichia coli ATCC 23282, Pseudomonas aeruginosa ATCC 10145), yeast (Candida albicans IMRU 3669) and filamentous fungus (Aspergillus niger ATCC 16404).

A new kind of surfactant with chelating properties named N-acyl ethylenediamine triacetate (N-acyl ED3A) of different hydrocarbon chain lengths was synthesized from anhydrous ethylene diamine, fatty acid chlorides (capryloyl, lauroyl, myristoyl, palmitoyl, stearoyl, or oleoyl chloride) and chloroacetic acid. Surface parameters and thermodynamic parameters were investigated. The prepared surfactants were tested for their biodegradability and their antimicrobial activity against different strains of bacteria, yeast, and fungi was investigated.

Introduction: A brief review is presented in the field of petroleum carcinogenesis. Epidemiological surveys in occupationally exposed populations postulate that long exposure to polycyclic aromatic hydrocarbons (PAHs) is carcinogenic. Several novel surfactants were investigated by Badawi and his collaborators on regulation of cancer growth. Other investigators recorded the role of cationic surfactants and pegylation.

Silicone surfactants have been widely used in our daily life and many industrial fields on the basis of their unusual properties. Only in the past decades has the use of silicone as a hydrophobic building block for the preparation of surfactants become common. The recent trend to combine silicone, polyoxyalkylene and carbohydrate moieties in the same molecule has resulted in a plethora of new compounds with new properties. In this article, we report the preparation of a series of “glycopolysiloxanes” surfactants with different molecular weights. They were structurally characterized by IR, 1H NMR and MS. Specifically, the critical micelle concentration (cmc), effectiveness of surface tension reduction (πcmc), maximum surface excess (Γmax), minimum surface area (Amin) and standard free energies of micellization (ΔG°mic) and adsorption (ΔG°ads) have been determined from aqueous surface tension measurements using Du-Nouy Tensiometer (KRUSS K6 type 4851) with a platinum ring. All the surfactants have good surface properties and have low cmc. The bacteriostatic power of these polymers was tested and compared under the same conditions in aqueous solution against common strains of Gram positive bacteria and strains of Gram negative bacteria.