Petroleum Crude Oil Research Articles

The Impact of Russia – Ukraine War on Global Economy

The invasion of Ukraine by Russia contributed to a notable rise in global prices of food and crude oil petroleum. The surge in the global food price index following the invasion was fueled by supply chain disruptions. In general, the incursion resulted in a continuous increase in inflation in both belligerent and non-belligerent nations. The following study shows how economic sanctions and regional conflict lead to an international energy crisis. Despite mediating countries like Turkey, it had a disastrous impact not only on geopolitical stability but also on economic development within and outside of Europe. The study used to assess the impact of Russia's invasion of Ukraine on global trade and business. This paper investigates the global economic growth and consequences of the Russia-Ukraine war over a four month period from December 2021 to March 2022. Russia invaded Ukraine on the 24th of February 2022.

Bioadsorption of crude petroleum oil from seawater using the marine alga Hormophysa triquetra mediated silver nanoparticles

The biosynthesis of silver nanoparticles, both economically and environmentally advantageous, uses algae extracts. In the current work, we extracted the marine brown alga Hormophysa triquetra (C. Agardh) kützing and used it to make silver nanoparticles (HAgNPs) which are characterized via UV–visible spectrophotometers, Transmission Electron Microscopy (TEM), Zeta potential, and FTIR then used them in the bio adsorption of crude petroleum oil from seawater, comparing them with H. triquetra aqueous extract. UV scan of the phycosynthesized silver nanoparticles achieved the highest absorption at 369 nm. TEM showed that the synthesized HAgNPs occur with smooth, spherical, and semispherical forms with sizes ranging from 12.04 to 20.67 nm, zeta potential illustrated that HAgNPs were charged with −22.1, The H. triquetra aqueous extract's FTIR examination identified several active groups like – OH, –C=C–, NO, –CH, CCl, –C ≡ C–H: CH which are responsible for the bioadsorption of crude petroleum oil. When extracting crude petroleum oil from seawater, HAgNPs worked better than its aqueous extract. The maximum removal % for light n-alkanes (Ln-alk), heavy n-alkanes (Hn-alk), and PAHs were 70.4 %, 71.63 %, and 75.38 % respectively for H. triquetra aqueous extract with adsorption capacity 889, 511, 273 μg/g at salinity 36 % and pH 5, while in case of HAgNPs the results were 75.81 %, 77.15 %, and 80.56 %, respectively with adsorption capacity 957, 550, 292 μg/g at the same salinity and pH.

THE ENERGY FACTOR IN THE DEVELOPMENT OF SAUDI ARABIA’S FOREIGN POLICY AT THE PRESENT STAGE

The article is devoted to the analysis of the energy factor in the formation and development of the modern foreign policy of Saudi Arabia. For decades, the foreign policy, as well as the entire economic system, of the kingdom has been directly dependent on the export of petroleum products and crude oil. Until the beginning of the 2000s western states were the main importers of Saudi energy resources, which directly affected Riyadh’s foreign policy orientation and often had a negative impact on the implementation of national interests and strategic objectives of state development. However, at the present stage, there is a process of formation of a multi-vector foreign policy of Saudi Arabia due to the intensification of trade and economic relations with non-Western states. When analyzing this aspect, the authors paid special attention to the main indicators of diversification of Riyadh’s leading partners, the results of the negotiation process on the kingdom’s accession to BRICS and the development of cooperation within the expanded OPEC format – OPEC+.

A quinazolinone based optical probe for the simultaneous determination of Fe3+and Cu2+ content in aqueous samples; An experimental and theoretical investigations

The chemosensor “3-((1-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)ethylidene)amino)-2-(4-(4-methylpiperazin-1-yl)phenyl)-2,3-dihydroquinazolin-4(1H)-one”, referred as “probe” was synthesized for the accurate quantification of Fe3+ and Cu2+ ions in various prepared samples originated from petroleum crude oil, catalyst, milk, and water. This probe serves as a naked-eye chemosensor, displaying distinct color changes in an aqueous medium, transitioning from light yellow to dark brown for Fe3+ and pale green for Cu2+ions. Remarkably, it displays exceptional dual selectivity for Fe3+ and Cu2+ ions, even in the presence of potentially interfering elements such as Na+, K+, Ca2+, Mg2+, Ba2+, Cr3+, Mn2+, Co2+, Ni2+, Zn2+, Cd2+, As3+, Sn2+, and Hg2+. Experimental assessments demonstrated the probe's high sensitivity, detecting concentrations as low as 0.017 µM for Fe3+ ions and 0.014 µM for Cu2+ ions. The 1:1 binding interaction between the probe and the metal ions was established through Job's plot, thermogravimetric analysis, and elemental analysis. Computational experiments were performed to determine the optimal geometry of the probe and its iron & copper complexes, revealing an octahedral geometry for both complexes. A comparative quantification analysis of Fe3+ and Cu2+ content across diverse aqueous samples was executed using both ICP OES and a new method. Notably, the results exhibited a favorable concordance with ICP OES outcomes, affirming the practical viability of these novel techniques for a wide range of samples.

Compositional differences of near-critical petroleum from closed pores to wellhead in Gulong shale oil play, Songliao Basin, NE China

The Gulong shale oil play located in northern Songliao Basin is a promising exploration target in China. Member 1 of Qingshankou Formation (Well H) with high thermal maturity was preferred to obtain pressure-retained cores, long-time exposed cores, and produced petroleum (crude oil and gas). The selected samples were subjected to sequential extraction, GC, GC-MS, thermal desorption–gas chromatography (TD-GC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. The compositional differences of in-situ fluids, residual bitumen trapped in open, confined, and closed pores, as well as wellstream, were systematically investigated. (1) In-situ fluid compositions, with a 30.8% proportion of nC1−5 in n-alkanes, were studied by TD-GC analysis on pressure-retained cores. Interestingly, limited amounts of C8- compounds were detected in long-time exposed bulk cores but were almost absent in exposed powder. Primally poor pore connectivity and partially adsorption or absorption of organic matter contribute to the retention of gaseous hydrocarbons. (2) Sequential extraction is a best method for obtaining compositions of fluid in pores with variable sizes. Aliphatic compounds of residual bitumen trapped in open pores are similar to those in confined pores, while polar compounds are more enriched in confined and closed pores. Originally connected pores in early oil window, has turned into confined or closed pores by compaction and cementation with increasing depth. (3) Wellstream compositions are significantly different from in-situ fluid compositions, especially in shale oil extraction. The proportion of gaseous hydrocarbons in the wellstream (76.2%) is considerably higher than that of in-situ fluids (34.1%). Comparison of aromatic hydrocarbons indicated that the wellstream is sourced from free fluids and partially adsorbed hydrocarbons in open pores. (4) Nitrogen and oxide compounds with a higher degree of condensation (higher DBE value) have poor movability, leading to extremely low content or even absence in crude oil. The compositional differences from in-situ fluids to the wellbore through the stimulated fractures are caused by selective adsorption of pore walls, confinement effect of nanopores and fluid phase changing. This study provides a window to the compositional differences of fluids released from different occurrence spaces and confirms compounds heterogeneity.

Efficiency of novel polyionic liquid toward the chemical separation of petroleum crude oil emulsions

AbstractIn the present study, a new polyionic liquid, PEST‐BU, were synthesized and characterized using proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, pendant drop technique, and thermal gravimetric analysis. The efficiency of PEST‐BU and its parent (PE‐ST) for separating petroleum crude oil emulsion was explored using several affecting parameters, including water ratio, separation time, pH, temperature, and demulsifier concentration. The results indicated that PEST‐BU exhibited higher separation efficiency (SE) than PE‐ST. In addition, the results revealed that the increased water ratio, separation time, temperature, and demulsifier concentration promoted the SE of PE‐ST and PEST‐BU. The data also showed that the optimal pH value to achieve maximum SE is 7; however, the SE of PE‐ST and PEST‐BU in acidic and basic mediums declined, possibly due to the increasing polarity of water droplets in these mediums, which increased electrostatic repulsion between them, increasing oil emulsion stability.

Chemical separation of petroleum crude oil emulsions using two new poly(ionic liquid)s

AbstractThis work aims to prepare new poly(ionic liquid)s (PILs) and use them for crude oil emulsion separation (EES). PILs were synthesized by an opening ring reaction of hexadecylsuccinic anhydride (HAS) using polyethyleneimine branched MW 600 (PEI) and triethylenetetramine (TTA) in a one‐step procedure, obtaining PILs, HSPI‐PIL, and HSTA‐PIL, respectively. Chemical structure, interfacial tension, aggregate size, and thermal behavior were verified using several techniques. The efficiency of HSPI‐PIL and HSTA‐PIL toward EES was explored using different parameters, including water content (WC), demulsifier concentration, temperature, and pH value. The results indicated that EES proportionally increased with increased WC and temperature. The data also revealed that increased demulsifier concentration improved EES at low WC, for example, 10% and 30%; however, this parameter showed no significant effect with crude oil emulsion containing high WC, for example, 50%. Furthermore, HSPI‐PIL and HSTA‐PIL gave the maximum EES values at a pH of 7, while they decreased in acidic and basic mediums.

Styrene-ethylene-butylene-styrene (SEBS) melt-blown fibers for oil spill remediation and oil barrier geotextiles

The distinctive oil gelation characteristics of styrene-ethylene-butylene-styrene (SEBS) thermoplastic elastomers were utilized for successful oil spill remediation with a range of different oils. Porous non-woven SEBS mat was fabricated via melt blown processing using a twin-screw extruder with customized blow die. After conducting rotational and capillary rheology investigations, a heightened melt-blowing temperature (300 °C) was applied to achieve an elevated melt flow index of SEBS for the melt-blowing process. Under optimized blowing parameters, a non-woven fabric was obtained consisting of fine fibers featuring an average fiber diameter of 20 μm. The material and oil absorption properties of the engineered SEBS fabric were compared to polypropylene (PP) nonwovens, a widely used material for oil spill mitigation that relies solely on adsorption and capillary forces to separate and immobilize spilled oil. SEBS nonwovens exhibited outstanding absorption and gelation properties for both crude petroleum and mineral transformer oil. Notably, SEBS demonstrated the ability to immobilize oil even under head pressure and at saturation, surpassing the capabilities of PP nonwovens (average fiber diameter 12 μm). This showcases a more efficient and cleaner method for remediating oil spills by effectively separating oil from water through absorption.

A coumarin-based optical probe for the quantitative determination of Fe3+ ions in water, petroleum crude oil, and catalyst samples; an experimental and theoretical investigation

A simple and sensitive optical probe, designated as "N-((9-benzyl-9H-carbazol-3-yl)methylene)-7-(diethylamino)-2-oxo-2H-chromene-3-carbohydrazide" was designed and synthesized for the accurate quantification of Fe3+ ions in water, milk, vegetables, petroleum crude oil, and catalyst samples in their prepared aqueous solutions. This probe (referred to as Probe-L) acts as a naked-eye chemosensor, at 254 nm, undergoing a noticeable color change from light yellow to medium dark brown in an aqueous medium. It exhibits exceptional selectivity for Fe3+ ions even in the presence of interfering elements such as Na+, K+, Ca2+, Mg2+, Ba2+, Cr3+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Al3+, Cd2+, As3+, Sn2+, and Hg2+. To determine the sensitivity of Probe-L towards Fe3+, we conducted experimental tests and found that it can detect Fe3+ ions with a concentration as low as 0.001 ppm. Through Job's plot, Thermogravimetric, and high-resolution mass spectrometry (HRMS) studies, we confirmed the 1:1 binding interaction between Probe-L and Fe3+ ions. In addition, computational experiments were conducted to ascertain the optimal geometry for Probe-L and its metal complex. The results indicated an octahedral geometry and the calculated HOMO-LUMO energy gaps were found to be 2.49 eV. We conducted a comparative analysis of the quantitative results derived from Probe-L in assessing Fe3+ content across various samples, juxtaposing them with the outcomes obtained through the ICP OES technique. Significantly, our findings demonstrated a favorable concordance with the ICP OES results, indicating the viability of the new techniques for a wide range of practical applications.

Socio-economic baseline for oil-impacted communities in Ogoniland: towards a restoration framework in Niger Delta, Nigeria

This study documents the socio-economic baselines in selected oil-impacted communities prior to the commencement of the Ogoni clean-up and restoration project. Adopting mixed approach consisting of semi-structured interviews, focus group discussions (FGDs), key informant interviews (KIIs), and household surveys, we surveyed the pre-remediation socio-economic conditions in the Ogoniland communities between July 2018 and March 2019. Results indicated that almost all respondents (99.6%) agreed that the smell of petroleum products or crude oil was evident in the air they breathed even as there were visible black particles (soot) in the respondents’ nostrils, on their clothes, and in water. The respondents described the ambient air as smoky and choked with an offensive smell. The household waters were smelly, brownish, or oily, and most respondents (76%) cannot afford to treat their water. Forty-two percent of the respondents who relied on fishing and farming for a living sought for alternative means of subsistence and acknowledged that oil pollution caused stunted growth and low crop yield. The majority of respondents (91%) reported falling fish catches, while the fish caught smell and taste of oil, lowering their market value and posing a potential health risk to consumers. It is evident that oil pollution has impacted the socio-ecological values and sustainable livelihood in Ogoniland. This study provides baseline data for monitoring post-remediation socio-economic improvements in Ogoniland. It also highlights areas of urgent intervention to improve livelihood, and access to basic amenities (e.g., potable drinking water), waste management infrastructure, and statutory policy changes for sustainable development in Ogoniland.

Extractive desulfurization of crude petroleum oil and liquid fuels using trihexyl tetradecyl phosphonium bis(2-ethylhexyl) phosphate ionic liquid

Abstract Increasing environmental concerns have led to the development of alternative methods for the desulfurization of petroleum crude oil and liquid fuels. Phosphonium-based ionic liquids (PILs) have recently demonstrated promising potential for effective extractive desulfurization (EDS). The present study focuses on the synthesis and application of trihexyl tetradecyl phosphonium bis(2-ethylhexyl) phosphate [THTDP][D2EHP] for EDS of synthetic model fuels and real crude oils. The molecular confirmation and thermal stability of [THTDP][D2EHP] were investigated using FTIR and TGA analyses. In addition, the conductivity, solubility, and viscosity of the synthesized ionic liquid (IL) were analyzed. The impact of reaction time, temperature, and sulfur compounds, such as thiophene, benzothiophene, and dibenzothiophene (DBT), on the desulfurization efficiency from synthetic fuels was also investigated. The results indicated up to 63 and 57 % sulfur removal from DBT-based model fuels and Iranian crude oil, respectively. The optimum extraction conditions were found as 1:1 IL/fuel mass ratio, 35 °C, and 30 min. The findings of this study provide valuable insights into the synthesis and utilization of PILs as promising solvents for extractive desulfurization of crude oil and liquid fuels.

Isolation and characterization of Candida tropicalis B: a promising yeast strain for biodegradation of petroleum oil in marine environments

The increasing interest in environmental protection laws has compelled companies to regulate the disposal of waste organic materials. Despite efforts to explore alternative energy sources, the world remains heavily dependent on crude petroleum oil and its derivatives. The expansion of the petroleum industry has significant implications for human and environmental well-being. Bioremediation, employing living microorganisms, presents a promising approach to mitigate the harmful effects of organic hydrocarbons derived from petroleum. This study aimed to isolate and purify local yeast strains from oil-contaminated marine water samples capable of aerobically degrading crude petroleum oils and utilizing them as sole carbon and energy sources. One yeast strain (isolate B) identified as Candida tropicalis demonstrated high potential for biodegrading petroleum oil in seawater. Physiological characterization revealed the strain’s ability to thrive across a wide pH range (4–11) with optimal growth at pH 4, as well as tolerate salt concentrations ranging from 1 to 12%. The presence of glucose and yeast extract in the growth medium significantly enhanced the strain's biomass formation and biodegradation capacity. Scanning electron microscopy indicated that the yeast cell diameter varied based on the medium composition, further emphasizing the importance of organic nitrogenous sources for initial growth. Furthermore, the yeast strain exhibited remarkable capabilities in degrading various aliphatic and aromatic hydrocarbons, with a notable preference for naphthalene and phenol at 500 and 1000 mg/l, naphthalene removal reached 97.4% and 98.6%, and phenol removal reached 79.48% and 52.79%, respectively. Optimization experiments using multi-factorial sequential designs highlighted the influential role of oil concentration on the bioremediation efficiency of Candida tropicalis strain B. Moreover, immobilized yeast cells on thin wood chips demonstrated enhanced crude oil degradation compared to thick wood chips, likely due to increased surface area for cell attachment. These findings contribute to our understanding of the potential of Candida tropicalis for petroleum oil bioremediation in marine environments, paving the way for sustainable approaches to address oil pollution.

Flame retardant and superoleophilic polydopamine/chitosan-graft (g)-octanal coated polyurethane foam for separation oil/water mixtures

The discharge of crude petroleum oils and their derivatives poses serious environmental challenges, which can be mitigated through oil/water separation. In this study, polyurethane (PU)/polydopamine (PDA)/chitosan-graft (g)-octanal foam was prepared by immersing of PU foam in PDA and chitosan-g-octanal solutions. The fabricated PU foam exhibited thermal stability, flame retardancy, and hydrophobicity/superoleophilicity. The coated PU foam can selectively absorb heavy and light oils from dynamic and static oil/water mixtures. The maximum sorption capacity for olive oil was found to be as high as 41.48 g/g. PU/PDA/chitosan-g-octanal foam also demonstrated excellent flame retardancy and the ability to quickly extinguish fire, as confirmed by the limiting oxygen index (LOI) test.

Effect of Petroleum Illegal Refining Activities on Cassava Plant in the Niger Delta

The evolution of illegal refining was briefly discussed leading to an experimental research of its effects on cassava plant which is a major staple food in the region. Two deactivated illegal refinery sites were selected for the studies; cassava plant (tubers, stem and leaves) samples were taken from these sites with a control and then analyzed for the concentrations of Heavy Metals, BTEX, PAHs and THC. The results show that the mean concentration of heavy metals in cassava tuber were Pb (5.31±0.17 mg/kg), Cd (6.44±0.23mg/kg), Cr (5.25±0.02 mg/kg), As (9.27±0.04 mg/kg), Zn (5.30±0.17 mg/kg), Cu (4.17±0.06 mg/kg), Ni (13.52±0.01 mg/kg) and Co (40.66±0.00) (mg/kg) for site A; while site B has Pb (0.15±0.03 mg/kg), Cd (0.107±0.06 mg/kg), Cr (0.167±0.03 mg/kg), As (1.83±0.02 mg/kg), Zn (0.063±0.02 mg/kg), Cu (0.079±0.04 mg/kg), Ni (0.113±0.01 mg/kg) and Co (0.082±0.05 mg/kg). The mean concentration values of heavy metals in cassava tuber were higher than the control mean values. Plant Concentration Factor was also calculated from the studies. Result also showed higher mean concentration values of BTEX and PAHs for cassava plant (tuber, stem and leaves) when compared with control values and WHO permissible limits for plants. The overall result indicates the contamination and pollution of cassava plant from both studied sites due to illegal petroleum crude oil refining activities.

Rhamnolipid assisted degradation of petroleum crude oil by indigenous Pseudomonas sp. WDE11 in seawater

Chronic and acute release of petroleum crude into oceans and seas leads to catastrophic effects on ecosystems and global climate. Employing effective strategies for the mitigation of petroleum crude pollution in the marine environment is the need of the hour. An indigenous strain of Pseudomonas (sp. WDE11), with polyaromatic hydrocarbon degrading abilities, degraded 1% petroleum crude oil (PCO) effectively in seawater on supplementation of glucose (1.0 g/L). Degradation was assisted by biosurfactant with low CMC (15.0 g/L) and was characterized as a rhamnolipid by FESEM-EDAX, LCMS, and FT-IR analysis. Glucose and inoculum depicted curvature amongst other tested parameters (incubation time, PCO, pH, and agitation speed via OPAT approach, and were subsequently optimized to maximum degradation using Pseudomonas sp. WDE11 by a 22 central composite design method. The highest degradation of 80 ± 0.15% of 1.0% PCO was achieved at 2.53 g/L glucose and 8.18% inoculum, as optimized conditions. GC/MS analysis depicted the degradation of all major hydrocarbons present in PCO on comparing with abiotic control. This study indicates the potential of Pseudomonas sp. WDE11 in the eradication of petroleum pollution from the contaminated marine environment under nutrient-limited conditions.

Machine Learning Applied to Predict Key Petroleum Crude Oil Constituents

AbstractSulfur compounds are the most important inorganic constituents of petroleum and require to be estimated beforehand because of their corrosive nature and other processing anomalies during crude oil processing. Paraffins, naphthene, and aromatics form the bulk of crude oil. Machine learning (ML) predictions of these constituents were made by training the ML model with a diverse industrial data set of 515 oils. The XGBoost model gave an excellent R2 in the range 0.88–0.99 for the bulk compounds. R2 for sulfur was in the modest range of 0.45–0.6, which improved significantly to 0.8 for additional inputs. ML applicability was thereby found to depend on the nature of the constituent. This work furthers ML‐based predictions, with the incentive of reducing expensive spectroscopic analytical methods.

Experimental study on nanoparticles-assisted low-salinity water for enhanced oil recovery in asphaltenic oil reservoirs

The purpose of this research is to look into the augmentation of silica nanoparticles (NPs) with low salinity (LowSal) brine for EOR. A series of analyses, including oil/water interfacial tension (IFT) and rock wettability tests were undertaken to determine an optimal dispersion to flood into a porous carbonate core with a defined pore size distribution. At 60 °C and 14.5 psi, the maximum drop (i.e., roughly 12.5 mN/m) in oil/water IFT by 0.3 wt.% brine occurred, but when 0.08 wt.% silica was added to the brine, the IFT reduced to 14.51 mN/m at 60 °C and 14.5 psi. The wettability analysis revealed a significant reduction in contact angle, from 142° to 72° and 59°, using 0.04 and 0.08 wt.% silica in LowSal brine, but the extent reduced by brine alone was insufficient. The results of rock pore size characterization were discussed in terms of the accomplishment of operating EOR in the porous medium in the presence of NPs. The addition of 0.08 wt. % silica to the injected brine resulted in an additional oil recovery of 16.3% OOIP as well as a significant shift in the endpoints/cross-points of the oil/water relative permeability curves. The findings of this research might help improve oil recovery from asphaltenic oil reservoirs or, more environmentally friendly, remediate petroleum crude-oil polluted soil.

Potential of spent fluid cracking catalyst (FCC) waste for low-carbon cement production. Effect of treatments to enhance reactivity

Spent fluid cracking catalyst (FCC) waste is produced to convert petroleum crude oil into gasoline, and its main component is a reactive zeolite known as faujasite. This paper studies low-energy treatments to enhance reactivity. When untreated, the spent FCC has outstanding activity, and a fast set which delivered significant strength (6–10 MPa) and a high mechanical index (MI=14). Calcination (up to 800 °C) is not enough to amorphize the faujasite and increase reactivity. However, NaOH-fusion is highly efficient. Even at low temperature (450 °C), NaOH-fusion breaks down the zeolite structure, dissolving Si4+ that forms cementing hydrates with high Ca/Si and Si/Al ratios which delivered high strengths. NaOH-fusion at 450 °C totally amorphized the zeolite resulting in high strength (9–13 MPa) and outstanding MI>22; superior to pozzolans, and closer to cementitious materials. Fusion at 600 °C reorganises some of the amorphous phase into a silicate whose hydrates provided the greatest strengths (over 16 MPa) and an outstanding MI of 24.Na2CO3-fusion at 600 °C did not alter the spent FCC but provided CO32− which formed calcite cements. These initially densified the matrix providing strength but lowered long-term strength and workability.Acid-etching partially dissolved spent FCC particles which improved early activity but caused a loss of soluble Si4+ and Al3+ that reduced the ultimate strength. Due to the low organic matter in the spent FCC, oxidation did not increase reactivity.The spent FCC is highly pozzolanic, it can safely reduce the embodied carbon of cements: concentrations of heavy metals are either traces or insignificant. Therefore, they can easily immobilise in a stable matrix.

Potential of some microbial isolates on diesel hydrocarbons removal, bio surfactant production and biofilm formation.

Potential of Arthrobacter citreus B27Pet, Bacillus thuringiensis B48Pet and Candida catnulata to produce biosurfactant using four different carbon sources (naphthalene, hexadecane, diesel and petroleum crude oil) was investigated. Removal of petroleum crude oil from aqueous culture and degradation of diesel were also determined using single and mixed culture of strains. The biofilm existence in single and mixed culture of strains was considered using naphthalene, hexadecane and diesel in culture medium. Cell surface hydrophobicity of A. citreus was higher than other isolates which also showed maximum surface tension reduction and emulsification index. As a whole, remarkable biosurfactant production occurred using petroleum crude oil as a carbon source in medium. A. citreus was found to be more robust than other tested strains in removal efficiency of crude oil due to its biosurfactant production capability. Statistically significant positive correlation was observed between biofilm existence and surface tension using diesel and hexadecane as carbon source. Overall diesel biodegradation efficiency by the mix culture of three applied strains was about 75% within a short period of time (10 days) which was accompanied with high biofilm production.

Characterization and formulation of an environment-friendly lubricant from Pongamia (Millettia Pinnata) oil using biodegradable additives

Global efforts are being undertaken to increase the automobile industry's energy efficiency, reliability, and environmental friendliness. There are techniques to lessen the environmental issues caused by machines, such as using lightweight materials, exhaust gas after-treatment, less toxic fuel, and controlled combustion. To decrease friction and wear, especially in engines and drive trains, proper lubrication is necessary at the required operating conditions for an automobile's safe and dependable operation. Mineral, synthetic, and semi-synthetic oils have been employed as lubricants; however, their disposal damages the ecosystems. Concerns about environmental deterioration are also raised by the emissions of metal traces such as calcium, magnesium, iron particles, and zinc due to burning these lubricants. Due to the limited supply of petroleum crude oil, these lubricants' present and future prospects are dismal. There is a worldwide quest for an alternative lubricant due to the environment being harmed by use of petroleum-based lubricants.The different characterization of the lubricant properties for the neat Pongamia base oil (PO) includes assessments of chemical, oxidative, rheological, thermal, and tribological properties. The fatty acid profile of PO has to be estimated using Gas chromatography–mass spectrometry. The Oxidative stability of PO should be estimated using the Differential scanning calorimetry (DSC) test. The rheological characterization should be done by evaluating kinematic viscosity, viscosity index, and dynamic viscosity. Tribological properties are studied using a four-ball tester tribometer. The lacking properties of neat PO is identified and improved using suitable additives such as antioxidants, viscosity improver, pour point depressants, anti-wear additives, etc. The biodegradability test of the formulated oil is done using bacterial turbidity assay and toxicity is checked of the final formulated oil. An IC engine test is done to check the performance of the engine and wear using formulated lubricant from PO.