Antifreeze Liquid Research Articles

Simultaneous quantification of seven glycols in antifreeze liquids using direct liquid injection gas chromatography coupled with mass spectrometry

Glycol‐based antifreeze liquids, commonly composed of ethylene glycol or propylene glycol, have important uses in automotive cooling, but they should be handled with care due to their toxicity. Ethylene glycol is highly toxic to humans and animals. A fast, accurate, precise, and robust method was developed for the simultaneous quantification of seven most important glycols and their isomers.MethodsGlycols were analyzed from diluted sample solution of coolants using gas chromatography coupled with mass spectrometry (GC–MC) in single ion monitoring mode.ResultsThe method was developed and validated for seven individual glycols (ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, and tripropylene glycol). Limits of detection (1–2 μg/mL) and limits of quantification (10 μg/mL) obtained were appropriate. The present method was applied for the determination of glycols in 10 different antifreeze liquids commercially available on the Romanian market, proving to be reliable.ConclusionsA method that requires only a two‐step dilution of antifreeze samples combined with direct liquid injection GC–MS was validated for the simultaneous quantification of seven glycols (and their isomers) in 10 different types of antifreeze liquids. The results obtained in the validation procedure proved that the GC–MS method is sensitive and precise for the quantification of glycols.

RETRACTED: Improve the rheological and thermal performances of the antifreeze liquids for cooling the batteries and radiators in automobiles via provide a new hybrid material composed from Carbon Nanotubes in Ethylene Glycol/Propylene Glycol

A new antifreeze hybrid nanofluid is developed in the present study. The hydrodynamic and thermal properties of the base fluids, such as water and Ethylene glycol are improved via examining the Nanoparticles. The final achieved nanofluid will be used for the cooling batteries; however, it might be applied for similar mechanical/ electrical systems such as through the radiators. The Carbon nanotubes are examined as dispersed nanoparticles. At first, an experimental part of producing the new mixture involving homogenizing and predicting the thermo-physical properties is presented. The numerical section will be reported regarding the heating/cooling simulations for the batteries. The proposed nanofluid in battery cooling systems dropped the battery temperature in different conditions. To investigate the effects of nanofluids, the energy equation was solved along with the energy source term arising from electrochemical reactions and ohmic losses. The temperature distribution inside the battery indicated a reduction in the maximum battery temperature when CNT nanoparticles were loaded. At a 50% state of discharge, the average battery temperature was 5.8°C lower when nanoparticles were CNT was loaded into EG + W. As the amount of state of discharge increased, the effect of the CNT presence intensified so that at a level of 95%, the temperature dropped by 6.9°C.

Self-formation of low frictional interface for tribologocal systems with silicon nitride in anti-freeze liquid

Self-formation of low frictional interface for tribologocal systems with silicon nitride in anti-freeze liquid

Evaluation of the Impact of Glycol Antifreeze on the Surfaces of Typical Construction Materials of Heat Exchangers

Abstract Glycol-based antifreeze liquids are used in two main areas: ICECS and HVAC. The standard research methods and requirements were developed to control the quality of fluids for the internal combustion engine cooling systems. Irrespective of the intended use, fluid tests are conducted with the same methods. This manuscript aims to study two types of antifreeze with standard methods. Then, the analysis was deepened to include microscopic techniques to identify the potential pitting corrosion centres on the surface of the selected metals. It was demonstrated that the application of microscopic techniques could significantly increase the chance to detect potential corrosion centres.

Low Cutoff Wavelength Etched SMS Structures Towards Verification of the Quality of Automotive Antifreeze

Optical fiber single mode – multimode – single mode (SMS) structures can be used as wavelength detection-based sensors. In this work, we focus on the performance at short wavelengths, where optical sources and detectors are less expensive. Here, a self-image band with a high transmission power is monitored in this short-wavelength range. In addition, the diameter and the length of the SMS structure have been optimized in order to improve the sensitivity of the device. In this sense, a maximum refractive index sensitivity of 305 nm/RIU was achieved by an etched SMS with a diameter of $34~\mu \text{m}$ . Furthermore, the obtained devices were used for testing the quality of automotive coolant and antifreeze liquid.

Control Strategy for Helicopter Thermal Management System Based on Liquid Cooling and Vapor Compression Refrigeration

With the continuous application of high-power electronic equipment in aircraft, highly efficient heat transfer technology has been emphasized for airborne applications. In this paper, a thermal management system based on an antifreeze liquid cooling loop and a vapor compression refrigeration loop is presented for high-power airborne equipment in a helicopter. The simulation models of the thermal management system are built in order to study its control strategy for the changing flight conditions. The antifreeze-refrigerant evaporator and air-refrigerant condenser are specially validated with the experimental data. A dual feedforward proportion integration differentiation and expert control algorithm are adopted in the inlet temperature of the cold plate and sub-cooling control of the refrigerant by regulating the compressor speed and the fan speed, respectively. A preheating strategy for antifreeze is set up to decrease its flow resistance in cold day conditions. The control strategy for the thermal management system is finally built based on the above control methods. In this paper, two extreme conditions are discussed, including cold and hot days. Both the simulation results show that the superheated, sub-cooling and antifreeze inlet temperature of the cold plate can be controlled at 3 to8 °C, −10 to −3 °C and 18 to22 °C, respectively. Under the same changing flight envelope, the coefficient of performance of the vapor compression refrigeration loop is relatively stable on the cold day, which is about 6, while it has a range of 2.58–4.9 on the hot day.

Investigation on cold start of polymer electrolyte membrane fuel cells with different cathode serpentine flow fields

The flow velocity and pressure distribution of the three cathode flow fields are simulated in this study. Larger pressure drop and more rapid flow rate reduce residual water, resulting in minimal ice formation during the cold start process. The simulation results show that the single variable cross section serpentine flow field has the largest pressure drop and the most rapid flow rate.The evolution of the temperature and the segment current density characteristics of three different cathode flow fields during cold start process is studied by printed circuit board technology. The results show that the 2 to 1 serpentine flow field has the best cold start performance and the best current density uniformity when cold start at constant voltage mode above −5 °C. However, the single variable cross section serpentine flow field has the best performance when cold start temperature is below −5 °C. Based on these results, cold start at −30 °C can be realized in 97s by using hot antifreeze liquid.

Suitability of base liquid in a nanofluid-laden solar flat-plate collector with emphasize on bioglycol

Ethylene glycol and propylene glycol are commonly used as thermal liquids in solar flat-plate collectors (FPCs). They are utilized as base liquid as well as for improving the stability of nanofluids in FPCs. The objective of the present paper is to introduce a renewable-derived bio glycol for use as base liquid in FPCs. The effect of base ratio (BR) of different glycol products on the performance of a conventional FPC and a nanofluidladen FPC is investigated in this paper to determine its suitability. MATLAB programming was employed for modeling the performance of the FPC operating with copper and cerium oxide nanomaterials. The results show that 20:80 bio glycol/water mixture is capable of enhancing the FPC’s energetic efficiency up to 72.1% which is higher than with either ethylene glycol and propylene glycol. The energy efficiency of a glycol-based nanofluid-filled FPC decreases with the base ratio of all three glycol products. Since bio glycol is a non-toxic and safe product, it can be utilized as a safe and environmentally-friend antifreeze and base liquid in nanofluid-filled FPCs.

Surrogate alcohol containing methanol, social deprivation and public health in Novosibirsk, Russia

Surrogate alcohol, i.e. alcohol not intended or not officially intended for human consumption, continues to play an important role in alcohol consumption in Russia, especially for people with alcohol dependence. Among the different types of surrogate alcohol, there are windshield washer antifreeze liquids; these products are the cheapest kinds of non-beverage alcohol available and thus likely to be used by the most deprived and marginalised groups such as homeless people with alcohol dependence. Although it is well known, that non-beverage alcohol is used for consumption by various groups in Russia, and although there are laws to prohibit the use of methanol as part of windshield washer antifreeze liquids for the very reason that such products could be used as surrogate alcohol, we detected products in retail sale which were a mix of water and methanol only. Methanol poses serious health threats including blindness and death, and there had been repeated methanol deaths from surrogate alcohol in Russia over the last years. If law-enforcement does not change for surrogate products, we can expect more methanol-resulting deaths in the most deprived and marginalized groups of people with alcohol dependence in Russia. In addition, ingredients with questionable safety profiles such as formic acid should also be prohibited in non-beverage alcohol products that are likely to be consumed as surrogate alcohol.

Statistical optimization of electrochemical oxidation of ethylene glycol using response surface methodology

Large amounts of ethylene glycol (EG) based antifreeze liquids are daily discharge into the receiving waters. The chemical oxygen demand (COD) detected in most of the lakes and rivers close to the discharge points exceeded 100,000mg O2/L. With such an amount, biological and chemical processes are inefficient to completely remove EG. In order to efficiently remove EG, electrochemical oxidation (ECO) of EG was carried out. Niobium Boron Doped Diamond (Nb/BDD) was used as anode whereas carbon felt was used as cathode. Different operating parameters including current intensity, treatment time, electrolyte concentration and pollutant concentration were tested. The application of 0.077A/cm2 of current density during 120min in the presence of 7.0g/L of Na2SO4 allowed 89.6±0.2% of COD removal with 490mg O2/L of residual COD. This result was far below the legislation standard set by the province of Quebec that allows the discharge of 800mg O2/L of COD. The efficiency of ECO process was attributed to both direct and indirect oxidation that generate strong oxidizing species (OH°, S2O82−, H2O2, etc.) capable of oxidizing organic matters on the surface of the anode and in the bulk of the solution.

Electrochemical degradation of ethylene glycol in antifreeze liquids using boron doped diamond anode

Large amounts of ethylene glycol (EG) based antifreeze liquids are daily discharge into the receiving waters. The chemical oxygen demand (COD) detected in most of the lakes and rivers close to the discharge points (industries, airports, etc.) exceeded 100,000 mg O2/L. With such an amount, biological and chemical processes are inefficient to completely remove EG. In order to achieve better results, electrochemical oxidation (ECO) of EG was carried out on a laboratory scale. Niobium Boron Doped Diamond (Nb/BDD) was used as anode whereas carbon felt was used as cathode in a rectangular electrolytic cell. Different operating parameters including current intensity, treatment time, anode material, electrolyte type, electrolyte concentration and pollutant concentration were tested. The application of 0.077 A/cm2 of current density during 120 min of treatment time in the presence of 7.0 g/L of Na2SO4 allowed 89.6 ± 0.2% of COD removal with 490 mg O2/L of residual COD. This result was far below the legislation standard set by the province of Quebec that allows the discharge of 800 mg O2/L of EG used for industrial purposes. The efficiency of ECO process was attributed to both direct and indirect oxidation that generate strong oxidizing species (ex: OH°, S2O82−, H2O2, etc.) capable of oxidizing organic matters on the surface of the anode and in the bulk of the solution.

Measurement of performance of thermoacoustic heat pump in a −3 to 160 °C temperature range

A thermoacoustic heat pump was constructed and tested. It was composed of a looped tube, a straight tube, and a regenerator. The looped tube contained the regenerator and was connected to the straight tube. The tubes were filled with nitrogen. When an acoustic wave was input to the tubes, a temperature difference formed along the regenerator. Our experiments showed that this heat pump could work as both a cooler and a heater. This heat pump achieved −39 °C as a cooler and 270 °C as a heater. Using antifreeze liquid and oil as heat media, the cooling and heating performance of the heat pump was measured within the temperature range from −3 to 160 °C.

Bioinspired Stimuli‐Responsive and Antifreeze‐Secreting Anti‐Icing Coatings

The detrimental impacts of icing on transportation and power industries are well‐known. Inspired by natural systems that secrete a functional liquid in response to stimuli, this work introduces an anti‐icing coating that responds to surface icing by releasing antifreeze liquid. It consists of an outer porous superhydrophobic epidermis and a wick‐like underlying dermis that is infused with antifreeze liquid. The functionality of the new coating is validated through condensation frosting, simulated freezing fog, and freezing rain experiments. In the tested conditions, the introduced anti‐icing skin delays onset of frost, rime, and glaze accumulation at least ten times longer than anti‐icing superhydrophobic and lubricant impregnated surfaces. Furthermore, the coating delays onset of glaze formation ten times longer than surfaces flooded with a thin film of antifreeze. In each of the icing scenarios, the fundamental mechanisms responsible for antifreeze release and their relation to required antifreeze replenishment rates are described.

Electrodialysis of salts from heat-transfer medium solutions using ion-exchange membranes

Recycling system that can recover the useful amount of glycol-based chemicals from the spent water-soluble heat-exchanging coolant liquids by electrodialysis (ED) is proposed in this paper. The majority of antifreeze liquids used is based on ethylene glycol (EG), but propylene glycol products are becoming more common. Glycol-based waste streams can originate from heat-exchanging liquids mediums, engine coolants or aircraft deicing fluids. Chemical additives as well as corrosion products and glycol degradation products were removed by ED with heterogeneous Ralex® AMH-PES and CMH-PES membranes, and pure glycol in water solution was produced. Laboratory experiments with model NaCl and EG solution were carried out. Real heat-transfer fluid from central heating equipment in the civil buildings was also demineralised by laboratory ED unit P EDR-Z (MemBrain s.r.o.). An efficient depletion of NaCl was achieved by reaching 99% desalination degree for the model EG solution. Ninety-eight per cent removal of salt additives was achieved by ED for EG sample from civil buildings cooling system.

Determination of Trace Amounts of Ethylene Glycol and its Analogs in Water Matrixes by Liquid Chromatography/Tandem Mass Spectrometry

Contamination of drinking water by ethylene glycol (EG) is a public health concern. EG causes adverse health effects in humans and animals, including cardiopulmonary and acute renal failure. EG and other glycols, such as propylene glycol (PG) are major components in antifreeze liquids, which may be the main source of contamination of ground water. A sensitive LC/electrospray ionization (ESI)-MS/MS method was developed to measure trace amounts of EG, diethylene glycol, and 1,2- and 1,3-PG in several water sources, including municipal tap, lake, river, and salinated water. In this method, glycols in water samples were derivatized with benzoyl chloride by the Schotten-Baumann reaction, followed by liquid-liquid extraction using pentane as the organic solvent prior to the LC/ESI-MS/MS determination. QC included analysis of a method blank and samples fortified at low and high levels. Analytical data showed excellent linear calibration for all observed glycols, with good precision and accuracy. The method detection limits for the studied glycols ranged from 1.9 to 6.1 ng/mL across the water matrixes tested. This method is suitable to help assess water quality in areas that may be prone to glycol contamination.

The Design of Solar Heating System for Oil Field Duty Room

Based on the natural environment of Gansu YuMen oilfield in china, aiming at the winter heating requirements for oil field duty room, using the solar heating system that make solar energy storage and auxiliary electric heating, selection of flat plate collector, tacking double working medium for heat exchange indirectly, use the antifreeze liquid as the hot working medium, use the water as the energy storage and heating medium. According to the room temperature and medium temperature, intelligent control system adjust and control the double medium circulation loop, automatic regulating the intermittent work time for auxiliary electric heating system, the problem of antifreeze and sand prevention be solved effectively in the extreme temperatures. Compared to the electric heater heating, it can realize energy saving and environmental protection, the energy saving effect more than 46%, having remarkable economic and social benefits.

Sensitive determination of ethylene glycol, propylene glycol and diethylene glycol in human whole blood by isotope dilution gas chromatography–mass spectrometry, and the presence of appreciable amounts of the glycols in blood of healthy subjects

Ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG) are widely used as components of antifreeze liquids for automobiles and in many other products. They occasionally cause severe poisonings when they are ingested in high doses. In this study, we established a detailed procedure for highly sensitive and simultaneous determination of EG, PG, and DEG in human whole blood by isotope dilution gas chromatography–mass spectrometry (GC–MS). A 0.25-ml aliquot of whole blood containing the glycols was mixed with 100 ng each of deuterated EG, PG, and DEG as internal standards. After centrifugation, the supernatant fraction was evaporated to dryness, derivatized with heptafluorobutyric anhydride, and the derivative was extracted with n-hexane; 1 μl of the n-hexane layer was subjected to GC–MS analysis. Contrary to our expectation, appreciable amounts of EG, PG, and DEG were found, even in human whole blood samples obtained from nonoccupational healthy subjects. Because such results have never been reported, in the early stages of this study, we suspected that our results were caused by carry-over of the glycols during the GC–MS procedure; thus, we cleaned the injection port, installed a new GC column, and washed the ion-source chamber. Despite these efforts, the clear peaks were detected at the same retention times as those of the authentic glycols for the extracts of healthy subjects, which led us to confirm the presence of the glycols in the blood of healthy subjects. Because the blank whole blood samples from healthy subjects already contained glycols, we constructed a standard addition calibration curve for each sample; the horizontal intercept point, where the straight calibration line intersected the horizontal concentration axis, showed the background concentration of the glycol. The calibration curves showed linearity in the range of 0.4–400 ng/ml for EG and DEG, and in the range of 4–2,000 ng/ml for PG, with correlation coefficients larger than 0.99. The limits of detection and limits of quantitation could not be exactly determined, because of the unavailability of blank human whole blood without each glycol. However, the values were estimated to be around or lower than 1 ng/ml from the signal-to-noise ratios of peaks for each glycol at the lowest concentrations obtained by selected ion monitoring. To validate the method, intraday and interday repeatability was tested; the percent relative standard deviations were 2.5–12.2 % and 0.8–8.5 %, respectively. Recoveries of the three glycols using whole blood samples of two subjects obtained by a unique method were 61.6–80.9 %. The concentration ranges (mean) of EG, PG, and DEG in whole blood obtained from ten subjects were 39.1–97.0 (64.0), 49.1–689 (181), and 8.08–22.9 (11.1) ng/ml, respectively. To test the effect of oral intake of PG, two volunteers ingested 100 ml of a commercially available energy drink containing 33.7 mg of PG, the safety of which was accredited by the Japanese Government. The PG levels in the blood of the two subjects increased by 74.0 and 158 % at 1 and 0.5 h, respectively, suggesting that the glycols present in human blood are largely derived from food. To our knowledge, the analytical method for the glycols presented in this article is the most sensitive among those so far reported. In addition, this is the first description of the presence of the glycols in healthy human subjects, which should be useful for setting cutoff levels of the glycols in poisoning cases.

Determining Hydraulic Conductivity for Air‐Filled Porosity in an Unsaturated Frozen Soil by the Multistep Outflow Method

Accurate simulation of snowmelt infiltration and runoff in frozen soil is important for many environmental and engineering issues in cold regions. It is well known that infiltration in frozen soil is dramatically reduced due to the impedance of ice crystals; however, it is very often inaccurately predicted because of limited data to parameterize the related processes. In this study, the hydraulic conductivity K(h) for air‐filled porosity in an unsaturated frozen soil was investigated by employing a multistep pressurized outflow method using antifreeze liquid. Comparisons of water flow in both partially frozen and unfrozen soils indicated that frozen soil significantly reduced K(h) due to the blocking effects of ice crystals. Based on one common K(h)‐based hydraulic equation, an impedance parameter for liquid‐filled porosity was extended to an apparent impedance parameter for air‐filled porosity. The apparent impedance factor Ωa is about 4 ranging from 0.5 to 6.5 as a function of matric potential. These findings represent significant new progress for estimation of Ωa by an experimental method that can be used for the estimation of snowmelt infiltration. We suggest that the current applied measurement method should be used and further evaluated for a variety of soil types.

Assessing the accuracy of Greenland ice sheet ice ablation measurements by pressure transducer

AbstractWe present a method of measuring ice ablation using an absolute pressure transducer as part of an automatic weather station (AWS) system, which we have installed in 17 locations on the Greenland ice sheet. The pressure transducer assembly is drilled into the ice, enclosed in a hose filled with antifreeze liquid. The pressure signal registered by the transducer is that of the vertical column of liquid over the sensor, which can be translated to depth, and ice ablation rate, knowing the density of the liquid. Measuring at sub-daily timescales, this assembly is well suited to monitoring ice ablation in remote regions, with clear advantages over other, well-established methods. The pressure transducer system has the potential to monitor ice ablation for several years without re-drilling, and the system is suitable for high-ablation areas (>5ma-1). A routine to transform raw measurements into ablation values is presented, including a physically based method to remove air-pressure variability from the signal. The pressure transducer time series is compared to that recorded by a sonic ranger for the climatically hostile setting on the Greenland ice sheet.

用太赫兹时域光谱技术判别防冻液和刹车油的真伪

Terahertz time-domain spectra technology can distinguish minor differences in structure and can be applied to physical testing and analysis.It provides a new experimental method for the identification of the organic chemical products and the study of spectrum more wide.In this paper,the optical property and spectroscopy of methanol,anti-freeze liquid and brake fluid are studied based on the terahertz time-domain spectra in the terahertz range.At room temperature,the time-domain spectra and the absorption spectrum in the 0.2~2.5 THz region of these samples are obtained in the environment full of nitrogen.Methanol,anti-freeze liquid and brake fluid have significant different absorption spectra in this wave band.The absorption peaks of methanol are located at 0.72 THz and 0.35 THz and the main absorption peaks of anti-freeze liquid and brake fluid are located at 0.62 THz.Experiment results show that whether methanol exists in anti-freeze liquid or brake fluid can be detected using THz-TDS terahertz time-domain spectra technology and then its quality can be judged.