Kerosene Dosage Research Articles

The preliminary investigation on the microplastic removal using column flotation: effects of kerosene on the floatability of microplastics

Abstract Microplastics (MPs), 1 to 5000 µm plastics particle, present grave environmental challenges due to their wide distribution in water and difficulty of removal due to their small size. As these particles persist in aquatic ecosystems, effective removal methods are urgently needed. The small size, low density, and high hydrophobicity of MPs not only facilitate their spread but also enhance their potential toxicity. MPs can adsorb toxic compounds and heavy metals, posing risks to both humans and wildlife through ingestion and inhalation. According to the properties of MPs, column flotation, a surface-based separation technique suitable for fine particles, might have a potential to remove MPs from contaminated water and to achieve the United Nation’s Sustainable Development Goals (UN-SDGs) #Goal14 “Life below Water”. In this study, the effects of kerosene dosage on the floatability of microplastics in column flotation were preliminarily investigated. The result showed that the kerosene could enhance the floatability and density of MPs also show significant effects on removal rate.

Enhanced mixed flotation of copper–molybdenum ore using dodecyl dimethyl betaine-emulsified kerosene as environmentally friendly collector

One way to decrease carbon emissions during mineral processing is to reduce reagent dosage. This research focused on utilizing dodecyl dimethyl betaine to emulsify kerosene, which significantly reduced the dosage of mixed flotation reagents for porphyry copper–molybdenum ores. A comparative analysis indicated that the addition of this emulsifier decreased the kerosene dosage by over 50% while enhancing the performance indicators. The analysis also showed that the directional adsorption of dodecyl dimethyl betaine at the oil–water interface increased the negative charge on the oil droplet surface, improving the stability and dispersion of the oil droplets in the solution. Furthermore, the emulsifier strengthened the adsorption stability of kerosene on the hydrophobic mineral surfaces. The emulsified kerosene predominantly exerted a physical adsorption effect on the mineral surfaces, with the highest strengthening effect observed for molybdenite, followed by pyrite and chalcopyrite. The collector, with a lower reagent dosage, improved porphyry copper–molybdenum ore processing and reduced carbon emissions.

Effect of Kerosene on the Growth of Nitrifying Bacteria Isolated From Soil

The environment is being subjected to an increasing amount of stress due to the alterations caused by the pollution of refined petroleum products such as kerosene. These changes might be substantial, which would have a big effect on the environment and, in turn, the farm output. Determining the potential toxicities of kerosene dosage response relationships to sensitive species, like soil microbes, is crucial. This investigation assessed how kerosene affected the nitrifying bacteria that were taken out of farmland's soil. We observed the population changes of the two nitrifying bacteria that were isolated from soil samples after they were exposed to varying concentrations of kerosene (0.5%, 1%, 2%, 5%, and 10%) for duration of 120 hours. Using a mineral salts media, the effects of kerosene on the two nitrifying bacteria were investigated. Samples were taken from the medium every 24 hours to gauge the growth of the bacteria, and a spectrophotometer was used to quantify the turbidity at 600 nm. The result showed that as kerosene concentrations were exposed to these bacteria over longer periods of time, the survivability of Nitrosomonas sp. and Nitrobacter sp. decreased. The toxicity studies' findings demonstrated that the degree of kerosene's toxicity to Nitrosomonas and Nitrobacter species depended on the quantity of pollutants present and the length of the contact period.

Using Kerosene as an Auxiliary Collector to Recover Gold from Refractory Gold Ore Based on Mineralogical Characteristics

Carbon–arsenic-bearing gold ore is a typical complex refractory gold resource. Traditionally, xanthate was often used as a flotation agent to separate gold minerals. But, in this paper, in order to reduce the cost of the agent, kerosene was used as an auxiliary collector, and the gold grade and recovery rate were increased by about 10 g/t and 5.5%, respectively. Through process mineralogy studies of the raw ore, it was found that the ore has an Au grade of 5.68 g/t, most of which is surrounded by sulfide ore, accounting for 79.46%. The main minerals are pyrite, arsenopyrite, and quartz, etc. Their content, shape, particle size distribution, and occurrence state were obtained via microscopic observation and statistical analysis. According to the results of process mineralogy, various flotation conditions were tested, including grinding fineness, kerosene dosage, collector dosage, foaming agent dosage, and the slurry pH value. The optimal chemical system and the process flow of “two roughing, three cleaning and two scavenging” were finally determined, and the concentrate product with a gold grade of 42.83 g/t and recovery of 91.02% was obtained, which verified the feasibility of the kerosene-assisted xanthate flotation of refractory gold.

Separation of Graphites and Cathode Materials from Spent Lithium-Ion Batteries Using Roasting–Froth Flotation

The separation of graphites and cathode materials from spent lithium-ion batteries (LIBs) is essential to close the loop of material used in LIBs. In this study, the roasting characteristics of the spent LIB materials are carefully analyzed, and the effects of roasting on the surface morphology and elemental chemical states of electrode materials are fully investigated by thermogravimetric analysis, SEM-EDS, and XPS to explore the roasting–flotation enhancement mechanism. Then, froth flotation is utilized to separate the graphites and cathode materials from the spent LIB materials. The optimal roasting temperature is determined by thermogravimetric analysis and the SEM-EDS analysis of the spent LIB materials. The results suggest that the organic binder can be effectively removed from the spent LIB materials at the roasting temperature of 500 °C, and there is almost no loss of graphite. The XPS results indicate that, in the process of roasting, the decomposition products of the organic binder can easily react with valuable metals (Ni, Co, and Mn) to produce corresponding metal fluoride. The flotation results of the spent LIB materials after roasting at the optimal conditions indicate that graphites and cathode materials can be efficiently recovered through roasting–froth flotation. When the dosage of kerosene is 200 g/t and the dosage of methyl isobutyl carbinol (MIBC) is 150 g/t, the cathode materials grade is 91.6% with a recovery of 92.6%, while the graphite grade is 84.6% with a recovery of 82.7%. The roasting–froth flotation method lays the foundation for the subsequent metallurgical process.

Agglomeration–Flotation of Microplastics Using Kerosene as Bridging Liquid for Particle Size Enlargement

Microplastics (MPs), defined as plastics with diameters between 1 and 5000 µm, are problematic pollutants in the environment, but their removal is challenging because of their minute size. One promising approach for their removal is flotation because MPs are inherently hydrophobic. However, the very small particle size of MPs lowers the probability of MPs-bubble collision and attachment that in turn affects the efficiency of the process. To address this challenge, we propose the use of agglomeration-flotation, a technique using kerosene as a bridging liquid to enlarge the particle sizes of MPs and make them amenable to flotation. In this study, the effects of kerosene dosage on particle size enlargement and floatability of six types of MPs with 100–1000 µm size fractions were investigated. The results showed that MPs with lower density compared with water could easily float in water without bubble attachment and particle agglomeration required. So, the effects of agglomeration on removal were negligible. In contrast, agglomeration using kerosene enhanced the floatability of MPs with high-density plastics. Moreover, image analysis was used to determine the agglomerated MPs’ particle size. The results indicate that kerosene could agglomerate the MPs and enhanced the removal of MPs by agglomeration-flotation.

Application of the response surface methodology to optimize the characteristics of weathered discard coals using the W/O HIP emulsion technique

ABSTRACT There is literature inadequacy for the application of high internal phase water-in-oil (HIP W/O) emulsion on agglomeration and flotation of weathered discards from coal discard dumps. In this study, two oxidized coal discards were beneficiated using W/O HIP emulsion technique. The performance of the W/O emulsion technique with an internal dispersed water phase of 95 vol% was compared with that of pure 100% kerosene. Response surface methodology was applied in the optimization of the two low-grade discard coals to generate mathematical regression equations to predict the response of the ash content and calorific value of clean coal products. The feed calorific value of 8.48 MJ/kg and 16.29 MJ/kg increased to 19.45 MJ/kg and 28.12 MJ/kg for discard coal 1 and 2, respectively. This was achieved with 5 kg/ton of emulsion binder, which is 0.25 kg/ton of organic dosage and at an agitation speed of 1800 rpm. A clean coal product with 19.05 MJ/kg and 27.20 MJ/kg was achieved under 5 kg/ton of pure 100% organic kerosene dosage. Statistical tools: Pred. R2 and Adj. R2 were established and confirmed the accuracy of the developed models. Overall, this study shows that the emulsion binder could upgrade weathered discard coal dumped for over three decades and achieved better quality product compared to kerosene.

Improving the yield of ultra clean coal by adding acetic acid and propionic acid in selective agglomeration

ABSTRACTIn this study, ash content lower than 1%, the ultraclean coal, using anthracite coal, is prepared by selective agglomeration flotation. ultraclean coal with lower ash is needed as electrode material and solid fuel, aim of obtaining lower ash content of ultraclean coal, dispersant is usually used to reduce ash content, but the yield will decrease. Therefore, clean coal yield can be further increased by regulator. For this purpose, the effects of stirring speed; dispersant (sodium hexametaphosphate) dosage, kerosene dosage, organic regulator (butyric acid; propionic acid; acetic acid; fumaric acid; maleic acid; ethylenediaminetetraacetic acid) on yield and ash content of clean coal were investigated in the experiments. The analyses of zeta potential, contact angle, x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), x-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), and Fourier transform infrared spectroscopy (FTIR) were used to illustrate the performance of the process. The results showed that the sodium hexametaphosphate and stirring speed had a significant effect on the reduction of clean coal ash content. Furthermore, adding acetic acid and propionic acid can improve the clean coal yield without increasing the clean coal ash content. Acetic acid was used as regulator, the yield of clean coal increased by 19.42%. At the same time, acetic acid and propionic acid are proposed as a method to produce microbubbles. This important discovery provides an optional method to obtain more target products for fine mineral flotation.

Agglomeration-Flotation of Finely Ground Chalcopyrite and Quartz: Effects of Agitation Strength during Agglomeration Using Emulsified Oil on Chalcopyrite

In flotation, the size of mineral particles is one of the most important parameters: when the size becomes fine, collision efficiency of the particles and air bubbles becomes low, causing low flotation recovery. To improve the collision efficiency and flotation kinetics, agglomeration using the emulsified oil of finely ground chalcopyrite (D50 = 3.5 μm) was carried out before flotation. In this study, the effects of agitation strength during agglomeration, kerosene dosage and potassium amyl xanthate (KAX) dosage on the flotation were investigated. Agglomeration using emulsified oil improved Cu recovery because the median diameter of agglomerate increased. With increasing agitation strength, KAX and kerosene dosages, Cu recovery was further increased. Agglomeration-flotation of a mixture containing chalcopyrite and quartz with 1:1 ratio (w/w, weight by weight) showed that Si recovery in froth was low and did not change with varying conditions (agitation strength, KAX and kerosene dosages); however, Cu recovery was significantly improved with increasing agitation strength, KAX and kerosene dosages, and thus the separation efficiency was improved.

Effect of polyethylene oxide on flotation of molybdenite fines

The processing of low-grade deposits of molybdenite is becoming more urgent with the gradual depletion of high-grade molybdenite ores in China. Low flotation efficiency has been suffered due to finer sizes liberation resulted from finely disseminated nature of low-grade ores and crystal anisotropy. In this study, kerosene was used to collect the molybdenite fines with different sizes, but even high dosage of kerosene could not achieve high flotation recovery for molybdenite particles with finer sizes. However, the presence of polyethylene oxide (PEO) considerably increased the flotation efficiency of molybdenite. The mechanism of PEO effect on the molybdenite flotation was studied by molecular dynamics simulation, Atomic Force Microscopy (AFM), Focused Beam Reflectance Measurement (FBRM), etc. Molecular dynamics calculation shows PEO molecules were more susceptible to (010) plane than (001) plane, thereby promoting the adsorption of PEO on the finer molybdenite particles. The wettability results indicate molybdenite particles become more hydrophobic in the presence of PEO, especially for the edge planes. Thereby the attachment time between bubbles and molybdenite particles reduced significantly. Moreover, in PEO solution, larger attractive forces were detected between molybdenite surfaces at >100 nm, agreeing with the rapid formation of large flocs in the molybdenite suspension. Thus, PEO not only improves the surface hydrophobicity but also induces the flocculation of fine particles, both of which improve the flotation performances of molybdenite fine particles.

A Novel Method for Improving Low-Temperature Flotation Performance of Nonpolar Oil in the Molybdenite Flotation

Nonpolar hydrocarbon oil (NHO) is one of the most extensively used collectors in the flotation of molybdenite due to its excellent selectivity. However, NHO has low sensibility at pulp temperature. At low temperatures (<283 K), although more kerosene is used, the recovery of molybdenite flotation is still lower than at room temperature. In this study, magnetizing treatment, which is an efficient, low-cost, innovative, and environmentally friendly emulsification method, was used to improve the flotation performance of NHO in low-temperature molybdenite flotation. The test results showed that, compared with unmagnetized kerosene (UMK), the optimum dosage of magnetized kerosene (MK) could be reduced by 11% at 298 K. At the same dosage of kerosene, the flotation recovery of MK was 3% higher than UMK at 278 K. The surface tension measurement results showed that the surface tension of MK rose periodically as the magnetic field intensity increased, and there was a maximum surface tension within each period. Further, the magnetic field intensity had the maximum flotation recovery of molybdenite at the maximum surface tension of MK. Combined with the analysis based on the Girifalco–Good theory and the static drop volume method of interfacial tension, the interfacial tension of kerosene–water was shown to decrease with the increase of the surface tension of kerosene. This finding indicates that the dispersibility of kerosene in pulp could be improved by reducing the size of oil droplets, thereby improving the molybdenite flotation recovery of kerosene at low-temperature pulp. It is helpful to improve the flotation recovery of molybdenite using NHO as a collector for low-temperature pulp (<283 K).

Flotation recovery of toner containing iron oxide from water suspension

Flotation of fine solids is important as the particles are not only contain valuable metals, which it is essential to recover, but negatively affect the environment. Fine particles often cause difficulties in flotation both surface chemistry and flotation kinetics. In this paper, flotation of toner particles was studied. The results show that toner particles, containing magnetite disseminated in organic matter, are fine in size (5–25 μm), and exhibit magnetic properties. The studies of contact angle revealed a high degree of hydrophobicity of toner surface, which resulted in high rates of particles attachment to air bubbles under stirring conditions of toner suspension. A multilayer coverage of the bubble surface with toner particles was observed, proved high bubble-particle and particle-particle interactions. Flocculation of toner as a result of either self-flocculation due to magnetic and hydrophobic properties of toner particles, or induced by collector was observed. Flotation kinetics tests were carried out to investigate the natural floatability of toner and the effect of kerosene on recovery and flotation kinetics of toner particles. Froth flotation can be used to recover toner from water suspension with no addition of collector. It indicates a reduction in chemicals consumption and environmentally friendly approach. Flotation kinetics of toner was described by second order flotation model. The findings revealed the effect of collector dosage to the rate of toner flotation. A significant recovery of toner 95.5% was observed at 2 min flotation time and it was higher compared to natural floatation of toner. High efficiency of flotation was achieved with small dosage of kerosene, which increased recovery and flotation rate of toner particles. Effect of concentration of solids in water suspension on flotation recovery was studied. Increasing the concentration of solids in the suspension from 1 g/l to 20 g/l resulted in the growth of flotation recovery from 78.13% to 96.72%. Despite this, the flotation rate constant for various concentrations of solids in the suspension was of the same order.

Innovative Methodology for Comprehensive Utilization of Spent MgO-Cr2O3 Bricks: Copper Flotation

Spent MgO-Cr2O3 bricks contain various heavy metals and are considered as a hazardous waste. In order to utilize the waste, a novel process to recover the copper from the spent bricks by flotation was developed. The mineralogical characteristics of the bricks, the mechanisms of metal penetration, and the effects of grinding time, emulsified kerosene dosage, collectors, and Na2S addition on the copper recovery were investigated. The results indicated that the spent bricks were mainly composed of periclase, magnesiochromite, copper, cuprite, and magnesium copper oxide. The copper penetrated into the MgO-Cr2O3 bricks from cracks and holes, and the copper oxides are easier than metallic copper, while the metallic copper is easier than its sulfides in infiltrating into the bricks. The optimum flotation parameters were 7 min of grinding time, 200 g/t of emulsified kerosene, 400 g/t of sodium isoamyl xanthate, and 400 g/t of Na2S. Based on these conditions, about 95 wt % Cu was recovered from the bricks by a clo...

Desulfurization Experimental Study on Flotation for High Sulfur Coal from Liupanshui, Guizhou Province, China

The total sulfur rate of the coal sample was 4.973%, the inorganic sulfur content was more than 60%, which was the main component in the coal sample. The effect of grinding fineness, flotation pulp density, collector and frother on coal flotation desulfurization were investigated in this paper to remove the inorganic sulfur. The results showed that it reached to the optimum desulfurization rate 54.7% when the optimum grinding fineness was 39.20% -200 mesh rate, pulp concentration was 80 g/L, kerosene consumption was 1.4 kg/t, 2#oil loading was 100 g/t, and the total sulfur content reduced to 2.72%. The optimized flotation condition determined by orthogonal experiments was as follow: pulp density for 60 g/L, kerosene dosage of 1.4 kg/t, 2#oil consumption of 100 g/t. In this case, total sulfur content reduced to 2.19%, the total desulfurization rate and the inorganic desulfurization rate were 55.96% and 92.89%, respectively.

Process to Reduce Ash in Flotation of Hard-to-Float Fine Coal

The most proportion of mineral impurities in this coal sample is Kaolin, which is very argilliferous and harmful for fine coal flotation. In this paper, the authors use recleaning process and add depressant inslurryto reduce the concentrate ash. The results show that the most appropriate depressant is sodium haxametaphosphate and the best flotation conditions are 80g/L feed concentration, 0.80l/t Kerosene dosage, 0.06l/t 2-octyl alcohol dosage, approximately 800g/t sodium haxametaphosphate dosage, and 4 minutes depressant action time. Consequently, the concentrate ash content decreases 5% than batch-floatation test.

Experimental Study on Extraction of Scandium from Hydrochloride Acid Leaching Liquid in TBP

The scandium concentrate used in the leaching experiment was obtained from the rare earth ore containing scandium in Yunnan Province, the sample used in experiment is leaching liquid containing scandium which the content of scandium is 3.6g/t, with complex impurity composition. The main influencing factors of extraction in hydrochloric acid solution were acidity, mixing time, phase ratio etc. and the condition experiments about these factors were conducted. The results show that extraction of scandium from the hydrochloric acid solution in TBP is feasible. The optimal conditions are that pH of the solution is 1.26, dosage of TBP is 5% of the solution, dosage of kerosene is 10% of TBP, mixing time is 3 min, phase ratio is 1:10, washing time is 2, the oscillating time of stripping is 1~2 min and the stripping rate reach 99.89%.

Preparation and Property Evaluation of Anionic Clean Fracturing Fluid

An anionic surfactant clean fracturing fluid was synthesized and its main performance was studied. The viscosity of fracturing fluid increased with increasing dosage of anionic surfactant. And the viscosity of fracturing fluid increased first, and then decreased with increasing concentration of KCl. The viscosity reached maximum 360 mPa•s when the KCl content is 2.7%. The results showed that the fracturing fluid had best temperature resistance and shear resistance performance under the condition of 100°C and at the shearing rate of 170 s-1. The sedimentation velocity of sand in the fracturing fluid are about 11.124, 18.840 mm/min at the temperature of 80°C and 120°C respectively. It indicated that the fracturing fluid has a better sand-carrying performance. The viscosity of fracturing fluid decreased below 5 mPa•s during 70 minutes when the dosage of kerosene was 3%, and the surface tension of the breaker fluid is 26.10 mN/m while the interfacial tension is 0.73mN/m. The low surface tension can meet the requirements of operation. The damage rate to the core is 7.65% and the fracturing fluid has lower damage to core than guar gel.

Aerosol flotation of low-grade refractory molybdenum ores

The characteristics of aerosol flotation, which include the effect of the concentration and particle size of kerosene aerosol on the molybdenum (Mo) flotation index and the effect of kerosene aerosol dosing method on the kerosene dosage and flotation time, were studied in the flotation of low-grade refractory molybdenum ores using kerosene aerosol. The results revealed that the particle size and concentration of kerosene aerosol had little effect on the Mo grade but had significant effect on the Mo recovery. A smaller particle size and a lower concentration of kerosene aerosol were beneficial to the Mo aerosol flotation. For the received Mo ore samples, the optimized particle size of kerosene aerosol was 0.3–2 μm and the optimized aerosol concentration was 14 mg/L. The compressed air atomizer had a more uniform distribution of aerosol particles than the ultrasonic atomizer, and the aerosol concentration was controlled easily, so the compressed air atomizer was more suitable for the research of aerosol flotation. Compared with conventional flotation in which kerosene was directly added into the ore pulp, the flotation time was reduced by ∼30%, and the dosage was decreased by ∼20% in aerosol flotation, while the Mo flotation index was similar.

Study of Flotation Effect of ST-1 Complex Reagent

There are lots of problems in coal flotation reagents. For example, it is difficult to disperse in coal pulp, it needs a large consumption, and its selectivity is poor. So this paper refers that kerosene can be made into compound kerosene by using different chemical products and surfactants, and then used for coal flotation. Tests proved that when the ST-1 Complex Reagent dosage is 500g/t, kerosene dosage is 900g/t, clean coal ash consistent is the same, and clean coal yield is closed, collector dosage saved 44.44%, and the fastest floating speed of clean coal is 99.3g/min, 4.8g/min fast than kerosene, Zeta potential is-28.9409mv after kerosene effect, Zeta potential is -13.2555mv after ST-1 Complex Reagent effect.

Removal of carbon constituents from hospital solid waste incinerator fly ash by column flotation

Hospital solid waste incinerator (HSWI) fly ash contains a large number of carbon constituents including powder activated carbon and unburned carbon, which are the major source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in fly ash. Therefore, the removal of carbon constituents could reduce PCDD/Fs in fly ash greatly. In this study, the effects of the main flotation parameters on the removal of carbon constituents were investigated, and the characteristics of the final product were evaluated. The results showed that loss on ignition (LOI) of fly ash increased from 11.1% to 31.6% during conditioning process. By optimizing the flotation parameters at slurry concentration 0.05kg/l, kerosene dosage 12kg/t, frother dosage 3kg/t and air flow rate 0.06m3/h, 92.7% of the carbon constituents were removed from the raw fly ash. Under these conditions, the froth product has LOI of 56.35% and calorific values of 12.5MJ/kg, LOI in the tailings was below 5%, and the total toxic equivalent (TEQ) of PCDD/Fs decreased from 5.61ng-TEQ/g in the raw fly ash to 1.47ng-TEQ/g in the tailings. The results show that column flotation is a potential technology for simultaneous separation of carbon constituents and PCDD/Fs from HSWI fly ash.