Waste Lubricating Oil Research Articles

Microbial Bioremediation of Spent Engine Oil: Current Advances, Challenges, and Future Directions

Study’s Excerpt Recent advancements in microbial bioremediation of spent engine oil (SEO) are presented. Specifically, the efficiency of bacterial and fungal species in degrading SEO hydrocarbons are reviewed. Key factors that influence degradation rates, such as strain specificity and environmental parameters in relation to different microorganisms are also highlighted. Full Abstract The extensive pollution of soil and water by spent engine oil (SEO) presents a considerable environmental hazard, especially because of its poisonous and recalcitrant characteristics. Traditional remediation approaches typically fall short in managing these toxins successfully, leading to an increased interest in bioremediation as a sustainable option. This review aims to compile current achievements/advancements in the microbial bioremediation of SEO, with emphasis on the effectiveness of several bacterial and fungal species in degrading the hydrocarbons in SEO under diverse environmental settings. Various studies published in the last decade (accessible via Google Scholar, Google, Scopus, and PubMed), reporting on microbial degradation rates on SEO, the impact of environmental conditions, and the efficacy of microbial consortia were objectively selected and analysed. Key findings showed that various genera such as Alcaligenes, Acinetobacter, Bacillus, Candida, Flavobacterium, Pseudomonas, and Rhodococcus were the most commonly reported microorganisms with potential SEO remediation because they have been reported to significantly degrade and used hydrocarbons in SEO as an energy source. Notably, Pseudomonas alcaligenes and Klebsiella aerogenes exhibited significant degradation rates of SEO, up to 68%, over 21 days under optimal conditions; Acinetobacter, Bacillus, Micrococcus, Flavobacterium, and Pseudomonas were found to exhibit a total hydrocarbon reduction of 86.7% over 60 days; while species like Ochrobactrum thiophenivorans were found to effectively degrade waste lubricating oil. However, there are significant differences in degradation rates among the reported species due to physiological factors such as temperature, pH, and available nutrients. Hence, it is inferential to conclude that microbial bioremediation shows promise in SEO management but its effectiveness is highly dependent on the type of microbial strain used and optimizing environmental conditions. Therefore, this review identifies several key knowledge gaps and proposed future research directions, such as the integration of bioremediation with emerging technologies to improve and ensure efficiency and scalability in real-world applications.

Enhanced lipase production and characterization from Aeromonas media VBC8: Applications in biodegradation of lubricating oil waste

This study aimed to explore the potential of a novel indigenous strain for the improved production of lipase from castor oil-contaminated soil. Among the various isolates, Aeromonas media VBC8 was found to be the most effective for lipase production. The effect of different inducer oils (olive, peanut, soybean, rice bran, sunflower, coconut, sesame, and fish liver oil) on the biomass of A. media VBC8 and its lipase activity was determined. Among the various oils assessed, fish liver oil exhibited highest lipase activity, with 89 U/mL with 9.1 g/L of biomass. Furthermore, Box-Behnken Design was used to optimize the cultural conditions resulting in an enhanced lipase activity of 1156 U/mL. The lipase was purified through ammonium salt (60 w/v %) precipitation, desalting and ion exchange column, achieving a yield of 16 % and specific activity of 98.4 U/mL. The purified lipase remained active over a wide range of pH 4.0–11.0 and temperature of 10–80 °C with maximum activity at pH 8.0 and 40 °C. SDS-PAGE analysis revealed the lipase's molecular weight to be 94 kDa. The study also evaluated the role of crude and purified lipase in the biodegradability of lubricating oil waste, achieving a maximum fatty acid conversion of 39 and 76 %, respectively, after 7 h incubation at room temperature.

Production of diesel-like fuel by catalytic co-pyrolysis of waste cooking oil and waste lubricating oil—an alternate energy source

Production of diesel-like fuel by catalytic co-pyrolysis of waste cooking oil and waste lubricating oil—an alternate energy source

The pyrolytic distillation of waste lubricants with waste oilfield scale into value-added fuel

The ever-increasing generation of waste materials has become a major environmental concern, highlighting the need for sustainable waste management strategies. This study explores the catalytic pyrolysis of waste lubricant oils using a waste oilfield scale as a low-cost solid catalyst to produce value-added fuel products. The pyrolytic distillation of waste engine oil was carried out in a manual distillation unit, employing a calcium carbonate (CaCO3) scale as a catalyst under various reaction conditions. Distillation experiments were conducted at 300 °C, 320 °C, and 350 °C, with and without adding NaOH and CaCO3 catalysts. The distillate fractions were characterized, and their properties were compared to standard fuel specifications. The results demonstrated that increasing the pyrolysis temperature and employing CaCO3 as a catalyst significantly enhanced the distillate yield and improved key fuel properties. At 350 °C, the distillate yield reached 56 % with 4 g of CaCO3, exhibiting desirable density (0.8049 g/cm3), viscosity (2.31 cSt at 40 °C), sulfur content (0.43 wt%), and a calorific value of 43,152 kJ/kg. Further, the distillate fractions were separated into gasoline (80–150 °C), kerosene (180–270 °C), and gas oil/diesel (270–350 °C) ranges, with the diesel fraction showing a promising cetane number of 51. The catalytic pyrolysis fuel (CPF) obtained from distillation with 4 g CaCO3 at 350 °C, followed by bleaching with CaO, exhibited excellent properties, including a density of 0.8297 g/cm3, viscosity of 2.71 cSt at 40 °C, pour point of −12 °C, sulfur content of 0.201 wt%, and a calorific value of 43,961 kJ/kg. The GC analysis revealed a paraffin-rich composition in the desired fuel ranges, contributing to the desirable fuel properties.

Waste Lubricant Oil Management: A Review of Technical Aspects and Regulatory Compliance

PT X, one of the largest coal mining companies in Indonesia, is located in Berau District, East Kalimantan. The company's mining activities produce waste lubricant oil, a dominant hazardous waste containing toxic materials that can significantly pollute the environment if not properly managed. Given the critical importance of managing waste lubricant oil, Indonesia has established several regulations for hazardous waste management. This study aims to evaluate both the technical aspects and regulatory compliance of PT X's waste lubricant oil management by comparing existing practices with technical criteria and applicable regulations. The methodology involves assessing the capacity of hazardous waste storage facilities based on the generation of waste lubricant oil, regulatory requirements, and transportation frequency, alongside compliance assessments of packaging, storage, and in situ utilization practices. Results indicate that PT X's storage capacity for waste lubricant oil is adequate and that its internal management practices fully comply with regulations. However, nonconformities were found in the hazardous waste management practices of third-party entities, particularly in packaging and storage. This research highlights the need for improved monitoring and regulation of third-party waste management practices to ensure comprehensive compliance and environmental protection.

Combination of Pseudomonas aeruginosa and Rhamnolipid for Bioremediation of Soil Contaminated with Waste Lubricant Oil

Combination of Pseudomonas aeruginosa and Rhamnolipid for Bioremediation of Soil Contaminated with Waste Lubricant Oil

A Comprehensive Study of Method Optimisation of Re‐Refining Spent Lubricating Oil

ABSTRACTUsed lubricating oil is generated by various machinery after extended operation. It is also referred to as spent mobile oil. Extremely hazardous waste lubricating oil is detrimental to the environment because it produces oxidative products when additives break down. Used lubricating oil is classified as a hazardous waste substance and has a negative impact on the environment. Polychlorinated biphenyls (PCBs), carcinogenic substances and other impurities make lubricating oil poisonous and pose a serious threat to human health and the environment. Re‐refining is considered the preferred technology for resource conservation, waste minimisation and reduced environmental hazards. The present study focuses on optimising the method of re‐refining waste lubricating oil. The effects of various operating parameters such as refining time, refining temperature, solvent‐to‐used oil ratio and flocculant dosage have been extensively studied to maximise the percentage recovery of lubricating oil. Optimum process parameters are (i) a refining time of 80 min, (ii) a refining temperature of 48°C, (iii) solvent‐to‐waste oil ratio of 5:1 (w/w) and (iv) a flocculant dosage of 2 g/kg of solvent; the optimum yield was found to be 75% with the solvent extraction method and 78% with the extraction–flocculation method, respectively. The purity and physico‐chemical properties of the recovered oil were thoroughly analysed using Fourier transform infrared spectroscopy and ASTM standard methods. It was concluded that refined oil can effectively reduce the ongoing oil crisis and create a clean, healthy environment.

Effects of Waste Lubricant Oil on Rheological Properties of Asphalt Binders: Implications for Sustainable Asphalt Mixture Production

Reusing waste lubricant oil as an environmentally-friendly alternative for disposal and transforming it into a value-added product is a promising solution. This study aimed to evaluate the rheological properties of asphalt binder (PG 64-XX) modified with waste hydraulic oil. Two levels of oil content, 3% and 5% by weight of the base binder, were added. Physical and rheological tests, including penetration, softening point, rotational viscosity, and performance grade (PG) tests, were conducted before and after subjecting the samples to the Rolling Thin Film Oven (RTFO), multiple stress creep and recovery (MSCR), linear amplitude sweep (LAS), and master curve procedures. Results showed that the addition of oil decreased the stiffness of the base binder, makingit more susceptible to premature cracking and instability. However, the mixture and compaction temperatures decreased with the oil addition. Overall, considering the investigated oil contents, the asphalt binders modified with waste hydraulic oil did not exhibit satisfactory performance. It is hypothesized that incorporating residual hydraulic oil in recovered asphalt binders may yield more favorable results.

Assessing the efficacy of three bio‐based flocculants in the reclamation of spent lubricating oil

AbstractThe current study encompasses a comprehensive assessment of three biopolymeric flocculants on the overall performance of recycling waste lubricating oil to achieve a higher percentage recovery, flocculation efficacy, and better quality of recovered base oil. The findings reveal that with experimental conditions such as (i) mixing time of 80 min; (ii) agitation speed of 400 rpm; (iii) reaction temperature 50°C; (iv) solvent to waste oil ratio 3:1 g/g; and (v) flocculant dosage 1 g/ kg of solvents, 1‐butanol and sodium alginate gives highest percentage yield of 91% followed by corn starch of 89.10% and xanthan gum of 87.18% as bio‐polymer flocculant. The effects of various process parameters of bio‐flocculants on flocculation efficiency are expounded. With the process parameters of (i) initial pH of 5.9, 6.0, and 6.2; (ii) mixing time − 59, 60, and 63 min; and (iii) solution temperature of 59, 60, and 62.2°C, maximum flocculation efficacy (% sludge removal) of 16.24%, 13.01%, and 14.09% were attained for the cases of refined oil treated with sodium alginate, corn starch, and xanthan gum, respectively. Results also reveal that the physicochemical properties of refined base oil treated with 1‐butanol and sodium alginate as bio flocculant are almost close to the virgin lubricating oil. The optimum recovery of high‐quality base oil with the adoption of green technology and solvent–bio flocculant combination can mitigate the environmental impact of waste oil and create an energy‐efficient sustainable condition for the regeneration of re‐refined base oil.

Effect of design parameters in nanocatalyst synthesis on pyrolysis for producing diesel-like fuel from waste lubricating oil.

Converting waste lubricating oil into diesel-like liquid fuels using pyrolysis presents a dual solution, addressing environmental pollution while offering a viable response to the fossil energy crisis. However, achieving high-quality fuel with a substantial yield necessitates the utilization of highly active and cost-effective catalysts. We report the development of Fe-Ni nanocatalysts, synthesized using a green approach and supported on TiO2, as a promising strategy for converting waste lubricating oil into premium-grade diesel-like fuel. To ensure efficient and effective pyrolysis processes, tailoring the synthesis parameters of these nanocatalysts is indispensable. In this study, we investigate the effect of design parameters on nanocatalyst synthesis, such as the concentrations of pre-catalysts and reducing agents, reducing time, and the amount of support material, and evaluate their impact on the quality and quantity of pyrolysis products. Through optimization of the synthesis process, a high quality diesel-like fuel with a product yield of about 54% at a mild reaction temperature of 400 °C was obtained. This study highlights the critical role of nanocatalysis in addressing persistent environmental and energy challenges while showcasing the potential of green nanocatalysts in sustainable waste-to-energy conversion processes.

Investigation of the Effects of Temperature and Catalyst on the Liquid Products of Waste Lubricant Oil Catalytic Pyrolysis

Catalytic pyrolysis is the process in which organic materials undergo catalytic thermal decomposition in the absence of oxygen. In this study, catalytic pyrolysis was conducted by heating waste lubricant oil in a modified catalytic reactor for 60 minutes at 350, 450, and 550°C. Furthermore, the effect of a catalyst on the pyrolysis of waste lubricant oil was investigated. The catalyst used was natural zeolite with particle sizes of 70/100 mesh, 200/250 mesh and > 400 mesh. The catalytic pyrolysis liquid products obtained were then analyzed to determine the viscosity, density, heat value and composition of carbon compounds. The results show that temperature, the addition of catalysts and the catalyst particle size affect the physical and chemical properties of liquid products. On the basis of these properties, liquid products can be grouped into several types of liquid fuels namely, gasoline, kerosene and diesel. The liquid products obtained with a catalytic pyrolysis at temperature 550°C and catalyst particle size of > 400 mesh have a density, viscosity, yield and heating value of 829.760 kg/m3, 1.9508 mPa⋅s, 45.33% and 10.981 calories/gram, respectively. The composition of carbon compounds in liquid products is 20.39% for C < 8 compounds and 79.61% for C8-C18 compounds. These liquids are similar to gasoline, kerosene and diesel.

Application of the Three-Reactor Hydrogenation Process in the Recycling Utilization of Waste Lubricating Oil and Study on the Catalyst Deactivation Mechanism

In the recycling of waste lubricating oil, the rapid deactivation of catalysts during the hydrotreating process limits its industrial application. In this paper, a three-reactor process is proposed for the...

Using Pistia stratiotes to Phytoremediate Oil and Grease from Greywater in Georgetown, Guyana

This study sought to investigate whether turbidity can be used as a surrogate variable for oil and grease pollution and to analyze the growth dynamic of Pistia stratiotes L. (water lettuce) to phytoremediate oil and grease from water. A quantitative analysis was done using a Completely Randomized Design (CRD) using seven treatments of greywaters with constant concentrations of nutrients (NPK) and emulsifier, and variable concentrations of waste lubricant oil which included a control over a 20-day period. The growth of the Pistia plants was monitored using the Leaf Area. The data were then analyzed using a one-way ANOVA. The results showed a significant correlation between turbidity and oil and grease. The greywater that was treated with Pistia stratiotes had as high as 85% reduction in oil and grease over a period of 30 days and as low as 65% in 20 days. Consequently, Pistia stratiotes was found to be highly efficient in phytoremediation of oil and grease pollution. The results also suggest that turbidity can be used as a surrogate variable for oil and grease pollution

Biodegradability enhancement of waste lubricating oil regeneration wastewater using electrocoagulation pretreatment.

As a sustainable management of fossil fuel resources and ecological environment protection, recycling used lubricating oil has received widespread attention. However, large amounts of waste lubricating-oil regeneration wastewater (WLORW) are inevitably produced in the recycling process, and challenges are faced by traditional biological treatment of WLORW. Thus, this study investigated the effectiveness of electrocoagulation (EC) as pretreatment and its removal mechanism. The electrolysis parameters (current density, initial pH, and inter-electrode distance) were considered, and maximal 60.06% of oil removal was achieved at a current density of 15mA/cm2, initial pH of 7, and an inter-electrode distance of 2cm. The dispersed oil of WLORW was relatively easily removed, and most of the oil removal was contributed by emulsified oil within 5-10μm. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that effective removal of the biorefractory organic compounds could contribute to the improvement of biodegradability of WLORW. Thus, the 5-day biochemical oxygen demand/chemical oxygen demand ratio (BOD5/COD) was significantly enhanced by 4.31 times, which highly benefits future biological treatment. The routes of WLORW removal could be concluded as charge neutralization, adsorption bridging, sweep flocculation, and air flotation. The results demonstrate that EC has potential as an effective pretreatment technology for WLORW biological treatment.

Biodegradation of Waste Lubricant Oil by a Novel Isolated Biosurfactant Producer- Achromobacter xylosoxidans PSA5

Waste lubricant oil (WLO) is a critical environmental issue because of its recycle and disposal challenges. A potent biosurfactant-producing bacterial strain was isolated by the enrichment culture technique using WLO as the sole carbon source from the oil-contaminated soils. The strain was identified as Achromobacter xylosoxidans (NCBI GenBank accession number: MW673656) based on the morphological, biochemical, and 16S rRNA gene sequencing. The preliminary characterization of the produced biosurfactant by biochemical methods revealed its glycolipid nature. The strain possessed extensive biodegradative potential and degraded various components present in WLO. The gas chromatography-mass spectrometry (GC-MS) analysis showed that the strain could degrade hydrocarbons (C7-C22) and diethyl phthalate, a priority pollutant, with a relative degradation of 43.87% within 7 days of incubation. The biodegradation of WLO by the strain confers its use in the bioremediation of oil-polluted environments, and the simultaneous biosurfactant production is undoubtedly a step toward greener technology.

Synergetic effect of liquid fuel derived from various waste feedstocks on performance, combustion and emission in a compression ignition engine

ABSTRACT Diesel engines being predominant in transportation sector are limited in addressing the sustainable development goals. The pressing need of environmental concern and fossil fuel depletion enforces the research community toward search of alternative fuels. In such context, waste materials have emerged as a promising feedstock for producing sustainable alternatives for diesel, given their abundance and their significance in waste management. Consequently, in this work, the waste feedstocks identified were waste plastics, waste lubrication oil, waste animal fat obtained from tanneries, waste cooking oil and waste tyres. For extraction of oil from these plastics, lube and tyre oil, pyrolysis was used and transesterification process was adopted for extraction of DLF from waste animal fat and waste cooking oil. The collected DLF was given for fuel property testing and found to be at par to utilize in a CI engine. It was then blended with diesel in the form of B80 (80% DLF and 20% diesel) and named as WTO B80, WLO B80, WCO B80, WPO B80 and WAF B80. To identify the differences in various parameters like combustion, performance and emission of CI engine at various engine loads, a bench test of a single-cylinder direct injection diesel engine without engine modification was done. The blend B80 of waste oil is analyzed in this work for its combustion characteristics and emission of various gases like nitrogen oxide (NO), carbon dioxide (CO2), carbon monoxide (CO), hydrocarbons (HC) and smoke. Among various liquid fuels tested, WPO B80 blend resulted in 32.81% BTE with NO emission of 1885ppm. The results also show emission of 67.2% of smoke, 0.18% of CO and 48 ppm of HC. The cylinder peak pressure for WPO B80 was at 72.85 bar and 48.04 J/deg CA peak heat was released, which concludes it as a suitable fuel for diesel engine compared to other fuels without any engine customization.

A Review on Recycle of Waste Lubricant Oil and its Properties Enhancement

Abstract: Continuous use and disposal of lubricating oil causes land, water and air pollution and also increases dependence on crude oil. This is the reason for the spread of disease, which affects every living being. Reuse of waste oil is the easiest option to avoid such pollution and dependence on crude oil. Another benefit of reusing waste oil is converting waste into money. Recycling waste lubricating oil has become an increasingly important aspect of sustainable waste management and resource conservation. Lubricant oil is made with 90% of base oil and rest of additives. In the lubricant oil, Base oil is never spoiled but after continues use of lubricating oil, it loses their properties because of continues friction, heavy load, and dirt metals absorbed hence it’s become waste oil. Here, we review the methods available to recycle the waste oil with the help of various treatment including acid treatment, clay treatment, adsorption, and solvents. The viscosity modifiers and additives used to make the SAE (Society of Automotive Engineers) grade recycled oil have also reviewed.

Mechanistic insights into co-pyrolysis of waste tires and waste lubricating oil: Kinetics and thermal behavior study

ABSTRACT The co-pyrolysis of waste tires (WT) with waste lubricating oil (WLO) can significantly improve the quality of products. The co-pyrolysis behavior of WT and WLO was investigated by using thermogravimetric analyzer. Three isoconversional methods, Flynn–Wall–Ozawa, Friedman and Kissinger–Akahira–Sunose, were used to calculate the activation energy of the mixture at the heating rates of 5, 10, 15, and 20K/min. The obtained data were used to determine the kinetic model and thermodynamic parameters. The results showed that WLO promoted the pyrolysis of WT. The synergistic effect was shown in the reduction of the activation energy of the mixture by 10%. The mean activation energy of the main decomposition stage is 90.8 kJ/mol. Moreover, the thermodynamic stability of reaction was determined by the calculation of change in entropy, Gibbs free energy, and enthalpy. The value of pre-exponential factor is 2.48 × 107/min, which means that the co-pyrolysis reaction is not a complex interface reaction. Among all the models, the 3D diffusion model best fits the co-pyrolysis mechanism judging by Malek master plot method. The reaction function was also determined. This study will provide basic knowledge into the co-processing of WT and WLO for predicting the performance of reactor and simulating the process.

Optimization of waste lubricating oil regeneration using acid‐clay process

AbstractWaste lubricating oil is non‐biodegradable materials. It is released into the environment and its disposal has become a global environmental issue due to its impact on all life aspects. The production of waste lubricating oil has recently increased rapidly. The aim of this work is to recover, optimize oil production process from waste lubricating oil. This was investigated using the acid‐clay process. Response Surface Methodology (RSM) approach was used to optimize the desludging reaction. The studied parameters were acid to oil ratio, contact time, temperature. The mixing ratio of acid to waste oil were selected in the range of 1:10 to 2:10 (v/v). Reaction time was in the range of 60–120 min. The predicted maximum viscosity index of 117.54 was obtained at the temperature of 40°C, 20% acid to oil ratio, and reaction time of 60 min. The results were assessed experimentally using five runs and the average value of viscosity index was 111.76 with standard deviation of 0.739 and error 4.91%. The samples obtained at optimum conditions were characterized by measuring flash point at 180°C, carbon residue of 0.487, kinematic viscosity at 100°C of 17cSt, the water content of 0.01%, ash content of 0.02%. Viscosity index of was found in complies with the Egyptian standards.

Enhanced syngas production from waste lubricant oil reforming with transition metal catalysts

Waste lubricant oil (WLO) which is a spent oil from vehicles, and machinery is often incinerated or landfilled, leading to environmental pollution and heavy metal-contaminations. At the same time WLO can converted to synthesis gas using steam reforming. In this study, catalytic steam reforming of WLO was performed in a micro fixed bed reactor at atmospheric pressure. Ni and Fe metals were loaded in a ratio of 5% and 10% on dolomite and olivine catalysts through impregnation method. The effects of equivalent ratio (ER) and metal (Ni and Fe) loadings on dolomite and olivine supported catalysts were investigated. Carbon-hydrogen conversions were significantly affected by ER with the optimum data at 0.88, which resulted in low CH4, and high H2 and CO. Nonetheless, the 5%Ni/dolomite exhibited superior overall activity with the highest overall conversion and hydrogen yield. In this case, hydrogen and carbon conversions were 65.71% and 66.38%, respectively, while H2 to CO molar ratio was 1.05 and the lower heating value was 6.76 MJ/m3. Hence, this suggests that the surface-active site of Ni on dolomite has high activity for C–C cleavage and water gas shift reaction. The conversion to H2 and CO was improved through methane and hydrocarbon steam reforming on the catalyst surface. Catalytic reforming of WLO not only enhanced synthesis gas generation which can be readily used as energy, a partial source of H2 or chemical feedstock but also as an appealing, sustainable, and economical waste management alternative.