Oil Soot Research Articles

Optical investigation on lubricant combustion characteristics under the ammonia-methane premixed environment

The combustion process is an indispensable energy conversion step in modern industry and energy production. Especially in high-performance engines and energy conversion systems, understanding and controlling the combustion process is critical to improving efficiency and reducing environmental pollution. As a key component of mechanical systems, the combustion characteristics of lubricants at high temperatures and pressures have a direct impact on system performance and emissions. This study investigated the combustion characteristics of lubricant films in an ammonia-methane premixed environment using Planar Laser-Induced Fluorescence (PLIF) and Planar Laser-Induced Incandescence (PLII). It focused on the effects of varying ammonia concentrations on the emission of soot and polycyclic aromatic hydrocarbons (PAHs) in the constant volume combustion vessel. Experiments varied the ammonia-to-methane molar ratios, initial oil film thickness, and base oil type to study their influence on the lubricant combustion characteristics. Results indicated that ammonia significantly reduced soot formation by altering the dynamics of NH* and OH* and impacting PAH distribution. For the lubricating oil soot formation factors, the increase of the initial mean oil film thickness was more obvious for the promotion of soot formation, the increase of the unsaturated hydrocarbon content in the oil film also promoted the generation of carbon soot to a certain extent, and the initial flame energy ratio had the least influence on the promotion of soot formation. Overall, the study contributed to the understanding of the formation mechanism of soot caused by lubricating oil in zero-carbon and low-carbon blended atmospheres and provided a new insight into the interaction between nitrogen-containing zero-carbon fuels and large-carbon-number hydrocarbons, which is of great significance for controlling soot emissions from engines under zero-carbon fuel blending.

Research and Analysis of Woodblock Printing Ink from the Qing Dynasty Used in the Shuyede Press of Shandong

Archival writing material is an important carrier to record and reflect archival content, and its material and durability are closely related to the life of archives. The “Shuyede” press in Shandong Province, which originated in the reign of Kangxi (1662 AD–1722 AD) in the Qing dynasty, printed many important archives and ancient books of the Qing dynasty (1644 AD–1911 AD). In order to explore the material composition of woodblock printing ink from the Shuyede press, modern analytical and detection techniques such as scanning electron microscopy–energy-dispersive spectrometry (SEM-EDS), Fourier-transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GC/MS), and pyrolysis gas chromatography–mass spectrometry (Py-GC/MS) were applied for the analysis and identification of the ink on woodblock plates from the Shuyede press. The results showed that two kinds of printing ink—pine soot ink and oil soot ink—used were in these woodblocks from the Shuyede press in the Qing dynasty in the collection of Shandong Museum, and the binding material in the ink was animal glue, indicating that both pine and oil soot inks were used as printing ink in the Qing dynasty.

A novel nanocomposite hydrogel with excellent photo-thermal and enhanced antibacterial properties based on China wood oil soot for acute wound healing

A hydrogel intended for potential use in wound dressing necessitates specific properties, including notable self-healing abilities, mechanical durability, and the ability to combat bacteria to address muscle and skin damage effectively. Moreover, the hydrogel must exhibit superior tissue adhesiveness to ensure seamless integration with the wound tissue during practical application scenarios. In this study, a novel photothermal China wood oil soot (CWOS)--based hydrogel (CH) dressing with high-strength and excellent photothermal performance was developed. Unlike traditional synthetic polymer networks, the novel nano-crosslinker fabricated by the CWOS optimized the dispersion of crosslinking points in the polymer network, resulting in outstanding mechanical properties (2000 % stretchability, 1.88 MPa strength). Massively reversible interactions between metal coordination (Ag-S) and hydrogen bonds gave the hydrogel excellent self-healing behavior. Besides excellent adhesiveness and biocompatible ability, the CH hydrogel combined with near-infrared ray radiation endowed highly antibacterial, alleviated inflammation, promoted angiogenesis, and promoted acute wound healing. Briefly, this multifunctional hydrogel can potentially aid wound healing for patients susceptible to bacterial infections. Its versatile properties offer promising prospects for its application in treating acute wounds.

Oxidative Stress and Acrosomal Status of Human Spermatozoa Subjected to Hydrophobic Carbon Soot Treatments.

The fourth industrial revolution extensively reshapes the reality we are living in by blurring the boundaries of physical, digital and biological worlds. A good example is the previously unthinkable incursion of nanoscale waste materials, such as soot, into the technologies for assisted reproduction. Although the rapeseed oil soot may efficiently enhance the progressive motility of human spermatozoa, it is yet unknown whether this material induces undesirable oxidative stress and premature acrosome reaction, endangering the sperm-oocyte fusion and blastocyst formation. In an attempt to clarify this issue, we reveal that the three-hour incubation of human semen mixed with three main types of soot does not cause oxidative stress and spontaneous acrosome reaction of the sperm. These unique findings are attributed to synchronous elimination and stabilization of the oxidants via hydrogen bonding to the acidic groups of the soot (i.e., C=O and/or C-O-C) and electron donation by its basic chemical sites (i.e., C-OH and/or COOH). Moreover, the soot nanoparticles are electrostatically attracted by discrete positively charged areas on the sperm head, increasing its negative charge and in some cases interfering the acrosome reaction. Such novel mechanistic insights emphasize the credibility of rapeseed oil soot to confidently shift from the purely diagnostic and therapeutic phases in reproductive medicine to research dealing with the effect of carbon nanomaterials on the embryo development and implantation.

A Vehicle Fleet Study to Investigate the Effect of B20 and B10 Usage on Engine Oil Degradation

The use of blended palm biodiesel has been implemented in Malaysia starting with B5 (5% palm biodiesel blended with 95% petroleum diesel) in 2011, B7 (7% palm biodiesel blended with 93% petroleum diesel) in 2014, and B10 in 2019. Palm biodiesel has been regarded as a reliable petroleum diesel substitute since 1995 following the research and development carried out by MPOB. Six trucks participated in the trial to evaluate the use of B20 and B10 through fleet testing and laboratory investigations. The trucks were divided into two groups according to fuel used. The field trial started in 2019 and ended in 2021. Engine oil and filter samples were taken at 5,000 kilometers intervals between service interval 30,000 kilometers. All the engine oil samples were within their operational service limits at each 5,000 kilometers sampling interval. The average viscosities of used engine oil in B20 group were 12.75 mm2 s-1 and for B10 group 12.98 mm2 s-1. The total basic number (TBN) values for the B20 group was 6.4 mg KOH g-1 and 6.3 mg KOH g-1 on average for B10 group. The wear and contaminants test showed the average iron particles concentrations for B20 and B10 groups were 22 ppm and 25 ppm respectively. In terms of engine oil evaporation, the average zinc and phosphorus concentrations reduced by only 20% for both vehicle groups. The average values for soot in oil showed that the B20 group had 10% less soot build-up compared to B10 group. The use of B20 had affected engine oil quality with minimal advantages for soot in oil and iron particle concentrations.

Manipulated sperm motility via soot nanoparticles-induced biochemical alterations in human seminal plasma

Obtaining spermatozoa with progressive motility, via postejaculatory activation with pharmacological agents such as theophylline and pentoxifylline, is crucial for the success rate of assisted reproduction in couples with severe male factor infertility. Regrettably, the possibility of premature acrosome reactions and impared oocyte function questions the practical applicability of phosphodiesterase inhibitors. The rapid development of nanotechnologies promotes the use of hydrophobic rapeseed oil soot as a non-cytotoxic biomaterial for sperm motility activation, but the scarcity of knowledge regarding the interactions of soot with components from the seminal plasma hinders the eventual commercialization of this cutting-edge approach. Aiming to eliminate this shortcoming, the current study shows for the first time how the soot nanomaterials alter the biochemistry of human seminal plasma. Upon 270 min incubation with soot nanoparticles, the activity of AST, ALT, CK, LDH and GGT enzymes in the seminal plasma of ten patients changes inversely to the registered sperm motility (i.e., lower enzyme activity, higher sperm motility and vice versa). This phenomenon is primarily related to termination of the enzymes-substrate binding or extraction of enzymes from the gametes via chemical bonding with the soot. These novel mechanisms depend on the physicochemical features of used carbon nanomaterials, revealing opportunities for predictable tuning of the sperm reproductive potential.

In situ nanocompression of carbon black to understand the tribology of contaminated diesel engine oils

The study has evaluated the role of soot, surrogated by carbon black (CB) experimentally, in affecting the performance of engine oils. It is very well known that the existence of soot in oil produces abrasive wear on contact surfaces. Other mechanisms influence the oil performance such as additives adsorption on soot and oil degradation due to the interactions with soot. Recent research has suggested the existence of another wear mechanism related to soot particles, which remains poorly understood. This study investigates the effect of soot interactions in engine oil on its mechanical properties. Carbon black particles (CBPs) were used in the experiments to simulate real soot in the engine. The microstructure and crystal structure of CBPs compared to real soot were investigated using transmission electron microscopy (TEM) and X-ray diffraction (XRD). In situ compression of the single particle was conducted in a scanning electron microscope (SEM) to evaluate the mechanical properties of fresh and aged CBPs with different sizes. The results show that aged CBPs are significantly harder than fresh CBPs, indicating that ageing in oil modifies the turbostratic crystal structure of CBPs and alters its mechanical properties, potentially affecting tribological performance.

Superhydrophobic soot as a mechanically robust, heat insulating and anti-corrosion protective coating for concrete surfaces

An artful strategy for protecting the concrete structures from cracking, flacking and corrosion is to make them non-wettable. Nonetheless, many hydrophobic modifiers are incompatible with the cement, hamper its hydration, possess weak alkali resistance and environmental toxicity, hence, retarding the adaptability of water-repellent chemicals in building materials. In this research, we propose a possible innovative solution to the aforementioned hurdles by drop-casting silicone-turpentine blend on pre-cured concrete and depositing rapeseed oil soot to convert the surface into superhydrophobic. The as-prepared silicone-soot composite inhibits the absorption of water and corrosive ions, thermally isolates the pristine concrete and withstands mechanical wear caused by abrasion, heavy rainfall, dynamic impact of sulfuric acid droplets and adhesion tape. Our invention is time-efficient, scalable and inexpensive, revealing opportunities for facile synthesis of durable superhydrophobic concrete on a large scale for aiding the construction of industrial facilities.

On the Development of Ultradurable Extremely Water-Repellent and Oleophobic Soot-Based Fabrics with Direct Relevance to Sperm Cryopreservation.

Nowadays, the tremendous progress of nanotechnologies and materials science facilitates the fabrication of universal and multifunctional superhydrophobic surfaces on a large scale. Yet, integrating icephobic and anti-bioadhesive properties in an individual water-repellent functional coating, for addressing the difficulties faced by cryobiologists, aircraft, and seacraft manufacturers, is quite tricky but feasible if using nonpolar soot nanoparticles, whose fragility, however, impedes their industrial applicability. Here, we advance the current state-of-the-art to an extent, permitting the introduction of economically affordable and ultradurable non-wettable soot-based coatings. The deposition of rapeseed oil soot, cyanoacrylate glue and fluorine compounds onto different fabrics confers the latter with superior tolerance to harsh mechanical and thermal interventions [e.g., scratching, blade scraping, liquid nitrogen immersion (T ∼ -196 °C), torsion and water jetting], while in the meantime retaining water repellency and oleophobicity. The as-prepared soot fabrics can stick continuously to the selected host surface and favor the recovery of ∼60% of the initial motility of human spermatozoa subjected to cryopreservation or being detached and utilized as standalone non-wettable membranes. Our invention may be considered as the first fundamental stage of safely (without any health concerns) transferring the soot in reproductive medicine and developing enhanced cryogenic and antibacterial medical devices.

Analysis of Ink for Woodblock Printing of Samguk Yusa (II) : Ink with High Solid Content

This study analyzes the physical and chemical properties of ink with high solid content for the woodblock printing of Samguk Yusa. Compared with pine or oil soot inks, the organic ingredients in ink for the woodblock printing of Samguk Yusa had a higher nitrogen concentration and the inorganic elements had a lower ash level. In addition, in the IR analysis, C=C bonds of 1650–1620 cm<SUP>-1</SUP> intensity were confirmed in the ink for the woodblock printing of Samguk Yusa, and the average particle diameter of these inks was confirmed to be about 61 nm. Because of the glue used in the ink’s production, the ink had a higher cohesive force and was less smeared on the Hanji. When dried in UV irradiation, it appears that the color of the printed part on Hanji will become more distinct.

Evaluation of lubricating-oil performance and emissions with lubricant formulations using ZDDP as the selected additive in GDI engines: a simultaneous study of VOCs and soot in oil

Evaluation of lubricating-oil performance and emissions with lubricant formulations using ZDDP as the selected additive in GDI engines: a simultaneous study of VOCs and soot in oil

Boron-rich boron carbide from soot: a low-temperature green synthesis approach

Boron carbide is a promising super-hard semiconducting material for refractory applications ranging from the nuclear industry to spacecraft. The present work is the first report of not only turning futile soot, containing carbon allotropes in varying composition, into boron-rich boron carbide (BC), but also developing it by a low-cost, low-temperature, and green synthesis method. The BC synthesised from gingelly oil soot is subjected to structural, morphological, and optical characterisations. The field emission scanning electron microscope shows beautiful flower-like morphology, and the thermogravimetric analysis reveals the high-temperature stability of the sample synthesised. The Tauc plot of the sample indicates a 2.38 eV direct bandgap. The formation of BC and boron-rich carbide evidenced by X-ray diffraction studies is confirmed through Raman and Fourier transform infrared spectroscopic signatures of B–C and C–B–C bonds. The fluorescence, power spectrum, and CIE analyses carried out suggest the blue light emission for excitation at 350 nm.

Effect of rGO@Fe3O4 on the tribological behavior of biodiesel soot-contaminated polyalphaolefin

The biodiesel soot interacts with engine oil and causes the wear of engine parts. In this study, we present the effects of rGO@Fe3O4 on the tribological behavior of the biodiesel soot-contaminated lubricating oil using a UMT-2 multifunction friction tester to ensure active control with respect to the role of biodiesel soot in engine oil. Three-dimensional laser scanning microscopy, field-emission scanning electron microscopy, and Raman spectroscopy were used to analyze the worn surfaces of the lower disc. rGO@Fe3O4 reduced the wear of the GCr15 steel specimens as an additive in the polyalphaolefin-6 base oil containing biodiesel soot. The tribological mechanism can be attributed to the formation of a protecting layer in the presence of rGO@Fe3O4 and the ability of the exfoliated Fe3O4 particles to repair the friction surfaces, enhancing the anti-wear property of polyalphaolefin-6 containing biodiesel soot.

Material‐Dependent Antagonistic Effects between Soot and ZDDP

AbstractWhile soot in engine oil is known to accelerate the wear of diesel and gasoline direct‐injection compression‐ignition engines, there is a lack of consensus on the wear mechanism though various hypotheses have been proposed in the literature. Particularly, some recently observed antagonistic effects between soot and a common lubricant antiwear additive, zinc dialkyldithiophosphate (ZDDP), while others did not. The discrepancy is, in part, explained by the strong alloy dependence of such antagonism discovered in this study. Four alloys, 52100 steel and M2, M50, and A2 tool steels, are tested in lubricants containing carbon black (CB, a soot surrogate) with and without ZDDP present. Adding the CB alone to the oil increases the wear rate for all steel alloys as expected. However, distinct wear performance is observed for the four steel alloys when ZDDP is introduced to the CB‐containing oil: while the 52100 steel has notable wear reduction, the three tool steels suffer significant wear increase. Comprehensive tribofilm characterization suggests that the Mo content in the steel alloy and the sulfur from ZDDP strongly influence wear behavior. The combination of CB/Mo‐catalyzed sulfidation and CB‐accelerated abrasion is hypothesized to be responsible for the high wear of the Mo‐alloyed tool steels.

An Alternative Procedure to Quantify Soot in Engine Oil by Ultraviolet-Visible Spectroscopy

Due to new pollutant emissions standards, internal combustion engines need several emission control strategies (and related procedures) such as exhaust gas recirculation, diesel/gasoline particulate filters, and selective catalyst reduction that allow them to comply with complete requirements defined on those standards. These strategies result in faster degradation of engine oil, one of the most relevant consequences of which is an increase in soot contamination level. All of these strategies facilitate soot generation. Consequently, soot is one of the most important contaminants present in engine oil. The main technique to measure the content of soot in oil is thermogravimetric analysis (TGA), but this technique has certain limitations. TGA requires a long and specific procedure and has limitations in measuring small concentrations of soot in oil. Therefore, the design of an alternative technique to quantify soot in oil is relevant. One alternative is Fourier transform infrared (FTIR) spectroscopy, but it also has limitations related to low concentrations of soot in oil. This work presents an alternative technique based on ultraviolet-visible (UV-Vis) spectroscopy that allows quantification of small soot contents in used engine oil samples and avoids potential interference from other typical contaminants or those related to measurement processes, such as sample cuvette material.

Impact of Oil Additive Characteristics on Biofuel Engine Wear Using Electron Microscopy and Confocal Microscopy

Soot particles are produced during combustion process in the diesel engine. These particles will later exhaust into the thermosphere and part of them will contaminate the engine oil. When the lubricant is contaminated with soot, diesel engine abrasion or in a worst-case scenario lubricant starvation occurs. This situation will eventually lead into engine ware. High volume of soot also raises acid level of the area. If this state co-occurs with high temperature of the engine and volatile gases during operation, engine corrosion may also be produced. This research study the effect of additive volume on the dispersion of soot in engine oil and effect of additive on size and volume of soot which affect to mechanism of ware in metal by tribology four-ball tester, image analysis by scanning electron microscope and particle size analysis by laser diffraction technique.

Study of the influence of emission control strategies on the soot content and fuel dilution in engine oil

Abstract The engine oil contamination by both particulate matter (PM) and fuel is becoming an important problem since strategies to control pollutant emissions in internal combustion engines (ICE) significantly increase their presence in engine oil. As a consequence, the engine oil loses its tribological properties compromising engine lubrication and leading to potential problems in engine such as wear, corrosion, etc. For that reason, the study of the oil degradation and contamination due to these strategies have a special interest to the engine manufacturers and engine oil formulators. In this paper, the engine oil soot content and fuel dilution is analysed under real engine conditions. The study is addressed from two different but complementary points of views. First, on-line measurements at several engine operating conditions are performed in order to further understand how the soot generation correlates with the oil soot content and other derived problems on oil performance. Then, experimental data available after the experimental campaign is used to calibrate a numerical model, based on Computational Fluid Dynamics (CFD), that estimate the amount of soot particles settled in the engine oil. Results show that soot particles are more present in oil when operating high load-speed conditions and during the Diesel Particulate Filter (DPF) regeneration cycles. Regarding the fuel dilution, delayed post-injections are critical since they significantly increase the amount of fuel in the engine oil. Numerical results also show the relationships between the soot particles generated during combustion and the amount of soot in engine oil, giving an enhanced comprehension of soot-in-oil deposition mechanisms.

Impact of oil aging and composition on the morphology and structure of diesel soot

HypothesisSoot is a black powder-like substance consisting of carbonaceous amorphous particles, formed by incomplete combustion of hydrocarbons. In the last decades, industrial research on lubricant oils has grown to develop more efficient formulations, mainly to reduce the formation of soot in oil so to increase engine lifetime. The comprehension of the mechanism of soot formation and particles growth/aggregation in times during real applications is of fundamental importance for the design of better performing lubricants. ExperimentsIn this work, we report on a multi-technique investigation of soot-in-oil samples, drawn from the oil sump of a direct-injected heavy-duty diesel engine at increasing working times in a standard engine test. Scanning Electron Microscopy, Small Angle X-ray Scattering and Dynamic Light Scattering are employed to study the evolution in term of soot size, morphology and fractal dimensions. FindingsOur results evidence that, in a complete lubricant formulation, exhaust oil viscosity evolution correlates well with the increase of soot amount inside the oil. Moreover, the growth of both primary soot particles and aggregates during the engine test is limited to about 24 and 200 nm, respectively, because of the active role of the dispersant present in the investigated oil.

Open sesame: Identification of sesame oil and oil soot ink in organic deposits of Tang Dynasty lamps from Astana necropolis in China.

Lamp illuminants evidence the exploitation of natural resources, animal and plant domestication, commerce, religious practices and nutrition of ancient populations. However, the physicochemical analysis of their major constituent—burned, degraded and aged mixture of triacylglycerols is imprecise and may lead to ambiguous interpretations. We applied proteomics to analyze fuel deposits from eight lamps dated by 6th to 8th centuries AD that were excavated at the Astana necropolis (Xinjiang, China) and determined their origin by identifying organism-specific proteins. Proteomics evidence corroborated and detailed the assignments of source organism relying upon comparative profiling of intact triacylglycerols by shotgun lipidomics. We found that ruminant (mostly, sheep) fat, cattle ghee and sesame oil were common combustibles in Astana and concluded that sesame as an oilseed appeared in China under Tang Dynasty concomitantly with the expansion of Buddhism.

Chemical characterization of diesel and hydrotreated vegetable oil (HVO) soot after reactive gas probing using diffuse reflectance FTIR spectroscopy (DRIFTS).

A chemical characterization of diesel and hydrotreated vegetable oil (HVO) soot has been developed using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) before and after the reaction with different probe gases. Samples were generated under combustion conditions corresponding to an urban operation mode of a diesel engine and were reacted with probe gas-phase molecules in a Knudsen flow reactor. Specifically, NH2OH, O3 and NO2 were used as reactants (probes) and selected according to their reactivities towards specific functional groups on the sample surface. Samples of previously ground soot were diluted with KBr and were introduced in a DRIFTS accessory. A comparison between unreacted and reacted soot samples was made in order to establish chemical changes on the soot surface upon reaction. It was concluded that the interface of diesel and HVO soot before reaction mainly consists polycyclic aromatic hydrocarbons, nitro and carbonyl compounds, as well as ether functionalities. The main difference between both soot samples was observed in the band of the C=O groups that in diesel soot was observed at 1719 cm-1 but not in HVO soot. After reaction with probe gases, it was found that nitro compounds remain on the soot surface, that the degree of unsaturation decreases for reacted samples, and that new spectral bands such as hydroxyl groups are observed.