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One concept for the safe storage and transport of molecular hydrogen (H2) is the use of hydrogen carrier systems which can bind and release hydrogen in repeating cycles. In this context, the liquid system based on isopropanol and its dehydrogenated counterpart acetone is particularly interesting for applications in direct isopropanol fuel cells that are operated with an excess of water. For a comprehensive characterization of diluted aqueous solutions of isopropanol or acetone with technically relevant solute amount fractions between 0.02 and 0.08, their liquid density, liquid viscosity, and interfacial tension were investigated using various light scattering and conventional techniques as well as equilibrium molecular dynamics (EMD) simulations between (283 and 403) K. Polarization-difference Raman spectroscopy (PDRS) was used to monitor the liquid-phase composition during surface light scattering (SLS) experiments on viscosity and interfacial tension. For comparison purposes and to expand the database, capillary viscometry and dynamic light scattering (DLS) from bulk fluids with dispersed particles were also applied to determine the viscosity while the pendant-drop (PD) method allowed access to the interfacial tension. By adding isopropanol or acetone to water, density and, in particular, interfacial tension decrease significantly, while viscosity shows a pronounced increase. The behavior of viscosity and interfacial tension is closely related to the strong hydrogen bonding between the unlike mixture components and the pronounced enrichment of both solutes at the vapor–liquid interface, as revealed by EMD simulations. For an aqueous solution with an isopropanol amount fraction of 0.04, minor variations in interfacial tension and viscosity were found in the presence of pressurized H2 up to 7.5 MPa. Overall, the results from this study contribute to an extended database for diluted aqueous solutions of isopropanol or acetone, especially at temperatures above 323 K. [ABSTRACT FROM AUTHOR]

The extractive distillation process using propylene glycol (IUPAC name: 1,2 propanediol) as an extractive agent for the separation of the isopropanol–water system was investigated in this work. A systematic procedure was set out to obtain the optimal design and process conditions for extractive distillation and solvent recovery columns using the PRO/II process simulator. Four thermally integrated flowsheets were proposed, implying the recovery of the sensible heat and latent heat from the hot streams in the process. To establish the economic feasibility of the proposed process, we calculated the total annual cost for all the simulated versions, and the proposed fully thermally integrated flowsheets could save up to 43.13% in terms of the utility costs and up to 15.57% in terms of the TAC compared to the conventional design. Thus, propylene glycol (PG) is found to be suitable as a new solvent for isopropanol dehydration, being comparable with other classical solvents used for the dehydration of alcohols. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic and other infectious diseases continue to threaten public health, particularly in densely populated informal settlements. Effective hand hygiene, supported by alcohol-based hand sanitizers (ABHS), plays a critical role in preventing disease transmission. This study assessed the quality, safety, and compliance of ABHS used in informal settlements around Cape Town. A total of 78 samples were collected from spaza shops, with 72 analyzed using gas chromatography with flame ionization detection. The results showed that 76% of ethanol-based sanitizers met compliance standards, while 24% did not. Isopropanol compliance (≥70%) was only observed in 36% of samples, with 64% failing to meet Centers for Disease Control and Prevention (CDC) guidelines. Overall, 74% of hand sanitizers complied with recommended alcohol concentrations by the U.S. Food and Drug Administration (FDA) and CDC, while 26% posed a health risk due to non-compliance. These findings emphasize the urgent need for stricter regulation and public education to ensure effective hand sanitizers are used, thereby reducing infection risks in vulnerable populations. The study aims to inform public health policies and improve regulatory standards. [ABSTRACT FROM AUTHOR]

A series of novel quinazolinone derivatives (E1−E31) containing the 1,2,4-triazole Schiff base moiety and an isopropanol linker were designed, synthesized and assessed as antimicrobial agents in agriculture. All the target compounds were fully characterized by 1 H NMR, 13 C NMR, and high-resolution mass spectrometry (HRMS). Among them, the structure of compound E12 was further confirmed via single crystal X-ray diffraction method. The experimental results indicated that many compounds displayed good in vitro antibacterial efficacies against the tested phytopathogenic bacteria including Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac), and Ralstonia solanacearum (Rs). For example, compounds E3, E4, E10, E13, and E22 had EC50 (half-maximal effective concentration) values of 55.4, 39.5, 49.5, 53.5, and 57.4 µg/mL against Xoo, respectively, superior to the commercialized bactericide Bismerthiazol (94.5 µg/mL). In addition, the antibacterial efficacies of compounds E10 and E13 against Xac were about two times more effective than control Bismerthiazol, in terms of their EC50 values. Last, the antifungal assays showed that compounds E22 and E30 had the inhibition rates of 52.7% and 54.6% at 50 µg/mL against Gibberella zeae, respectively, higher than the commercialized fungicide Hymexazol (48.4%). [ABSTRACT FROM AUTHOR]

This study explores the effectiveness of alcohol injection as a stimulation treatment to mitigate water blockage in the vicinity of the wellbore. Over the years, water blockage has emerged as a recurring challenge within the oil and gas industry, leading to diminished well productivity. In a commingled reservoir with multiple layers, when a producing well is shut-in for well intervention or workover, water may encroach from water zones into the oil-bearing formations through the wellbore due to pressure differences between the layers. Water encroachment can have a significant impact on the production of a well. It can reduce the oil production rate, increase the water cut, and shorten the well's lifespan. Therefore, it is essential to take steps to mitigate the water encroachment effect in commingled reservoirs. This study explores the use of alcohol injection to reduce transition time and remediate formation damage in commingled oil reservoirs. Limited studies have shown that alcohol has the potential to enhance fluid relative Permeability in gas condensate reservoirs and reduce condensate banking near the wellbore. However, this approach has not yet been tested in commingled oil reservoirs. A series of core flooding tests were conducted using Berea sandstone cores and a Texan light crude oil sample. The core flood setup was designed to represent the water blockage condition in the formation. Two different alcohols were tested: isopropyl alcohol (IPA) and Methanol. Experimental results showed that mutual solvents significantly reduce water blockage and shorten the transition period. However, asphaltene precipitation may become a problem with increasing the molecular weight of injected alcohol.

The COVID-19 pandemic and other infectious diseases continue to threaten public health, particularly in densely populated informal settlements. Effective hand hygiene, supported by alcohol-based hand sanitizers (ABHS), plays a critical role in preventing disease transmission. This study assessed the quality, safety, and compliance of ABHS used in informal settlements around Cape Town. A total of 78 samples were collected from spaza shops, with 72 analyzed using gas chromatography with flame ionization detection. The results showed that 76% of ethanol-based sanitizers met compliance standards, while 24% did not. Isopropanol compliance (≥70%) was only observed in 36% of samples, with 64% failing to meet Centers for Disease Control and Prevention (CDC) guidelines. Overall, 74% of hand sanitizers complied with recommended alcohol concentrations by the U.S. Food and Drug Administration (FDA) and CDC, while 26% posed a health risk due to non-compliance. These findings emphasize the urgent need for stricter regulation and public education to ensure effective hand sanitizers are used, thereby reducing infection risks in vulnerable populations. The study aims to inform public health policies and improve regulatory standards.

AbstractThe mass transfer performance of isopropanol (IPA) absorption by triethylene glycol (TEG) aqueous solution in a spray-bed absorber was investigated, and the mass transfer coefficients predicted by an artificial neural network (ANN) and response surface methodology were compared in this study. The operating variables affecting the mass transfer performance of a spray-bed absorber include the gas and TEG fluxes, concentration of IPA, concentration of TEG aqueous solution, and operating temperature. The experimental results demonstrated that the mass transfer coefficient of a spray-bed absorber increased with increases in gas and liquid fluxes and decreased with increases in concentration of IPA. The Back-Propagation algorithm in the ANN model was selected to predict the mass transfer coefficients of the spray–bed absorption system. Hidden layers with 2, 4 and 6 neurons respectively were set to analyze the effect of the number of neurons on the target value, and then different transfer functions were used to compare the accuracy in predicting mass transfer coefficient. Finally, the influences of the number of hidden layers and different learning rules on the prediction of mass transfer coefficients were examined. The simulated results showed that the average error of the ANN using the TanhAxon transfer function, the Conjugate Gradient learning rule, two hidden layers, and 6 neurons in each hidden layer was within 1%. The results not only verified the successful establishment of the experimental device but also proved the accurate prediction of mass transfer coefficients by the ANN model. [ABSTRACT FROM AUTHOR]

Summary: This study focused on the preparation of lipid concentrates with high contents of bioactive molecules. Different one‐step and two‐step extractions with non‐halogenated solvents (hexane, HX; isopropanol, IP) were carried out on Patagonian squid (Doryteuthis gahi) discards. As a first step, HX extractions (one, two or three times) were carried out. The resulting substrates were extracted with IP (two, three or four times). Analysis of lipid extracts included total lipid, phospholipid (PL) and tocopherol values, and fatty acid (FA) profile. HX extractions led to remarkable α‐ and γ‐tocopherol values (ca. 1400 and 23 mg kg−1 lipids, respectively); no effect (P > 0.05) of the number of HX extractions was observed. IP extracts provided high PL values (383–501 mg kg−1 lipids); the highest average values were detected with four IP extractions after three HX extractions. Values obtained for tocopherols and PLs were higher (P < 0.05) than those obtained by employing the conventional (chloroform/methanol, 1:1) lipid extraction (ca. 496 and 11 mg kg−1 lipids and 400 g kg−1 lipids, respectively). Range values detected for eicosapentaenoic and docosahexaenoic acid values and the ω3/ω6 FA ratio were similar to those obtained by the conventional procedure. A valuable procedure is proposed for obtaining PL‐ and tocopherol‐enriched concentrates from marine waste with non‐halogenated solvents. [ABSTRACT FROM AUTHOR]

In this study, the effects of methanol, ethanol, isopropanol, and Diethylene glycol monomethyl ether (di-EGME) added to jet fuel in certain proportions on the properties of jet fuel such as density, viscosity, freezing point, and ignition point was examined. By adding 2%, 5%, 7%, and 10% of each additive to JP-8 fuel, the required mixture was obtained and tested in the relevant devices. As a result of the experiments, it was determined that the density value of JP-8 fuel was 797 kg/m³ and this value did not vary greatly in the mixed ethanol, ethanol, and isopropanol, but with the addition of di-EGME, it increased significantly and reached 814.5 kg/m³. It was observed that the viscosity value did not vary greatly with the addition of methanol and ethanol but increased to 1.298 mm/s² with the addition of 10% isopropanol and to 1.98 mm/s² with the addition of di-EGM. The ignition point value of JP-8 fuel, which is 46 °C, was measured to be 40 °C with the addition of 10% methanol, 43.4 °C with the addition of 10% ethanol, 42.9 °C with the addition of 10% isopropanol, and 55.4 °C with the addition of di-EGM. The freezing point value of JP-8 fuel, which is - 56.7 °C, was measured as -61.7 °C with the addition of 10% methanol, -62.1 °C with the addition of 10% of ethanol, -57.6 °C with the addition of 10% isopropanol and -54.6 °C with the addition of di-EGM. [ABSTRACT FROM AUTHOR]

Background: Alcohol poisoning is a significant global problem that has become an epidemic. The determination of the alcohol type is hereby essential as it may affect the course of the treatment; however, there is no routine laboratory diagnostic method for alcohol types other than for ethanol. In this study, we aimed to define a simple method for alcohol type differentiation by utilizing a combination of breathalyzer and spectrophotometrically measured serum ethanol results. Methods: A breathalyzer and spectrophotometry were used to measure four different types of alcohol: ethanol, isopropanol, methanol, and ethylene glycol. To conduct serum alcohol analysis, four serum pools were created, each containing a different type of alcohol. The pools were analyzed using the spectrophotometric method with an enzymatic ethanol test kit. An experiment was conducted to measure the different types of alcohol using impregnated cotton and a balloon, simulating a breathalyzer test. An algorithm was created based on the measurements. Results: Based on the results, the substance consumed could be methanol or isopropanol if the breathalyzer test indicates a positive reading and if the blood ethanol measurement is negative. If both the breathalyzer and the blood measurements are negative, the substance in question may be ethylene glycol. Conclusions: This simple method may determine methanol or isopropanol intake. This straightforward and innovative approach could assist healthcare professionals in different fields with diagnosing alcohol intoxication and, more precisely, help reducing related morbidity and mortality. [ABSTRACT FROM AUTHOR]

A common issue in studies on liquid-phase chemical processes is that the natural solid nanoimpurities present in reagent-grade chemicals are ignored. Little is known about these impurities' nature, sizes, concentrations, and behavior, yet they significantly affect the efficiency of antiscalants in municipal and laboratory solutions. Recent research has focused on: (i) estimating nanoimpurity concentrations in in-house deionized water and semiconductor-grade isopropanol using "light sheet" optical ultramicroscopy, and (ii) visualizing antiscalant sorption on these impurities. Using a fluorescent-tagged antiscalant aminobis(methylenephosphonic acid) (ADMP-F), we tracked its affinity to particulate matter in deionized water and reagent-grade KCl solutions. Our study showed that the total concentration of nanoparticles with a size larger than 20 nm is about 106 units/mL in deionized water and 105 units/mL in isopropanol. Extrapolation of these values to a size ≥1 nm resulted in concentrations of 1011 and 108 units/mL. The addition of KCl or ADMP-F significantly increased foreign nanoparticle populations. ADMP-F is selectively adsorbed by only some impurities, while most antiscalant molecules remain as true solution. To our knowledge, this is the first instance of fluorescently labeled aminoalkylphosphonates being able to differentiate particulate matter traces in reagent-grade purity solutions. Therefore, the role of nanoparticles as crystallization centers should be seriously reconsidered, especially in their important application in scale inhibition. [ABSTRACT FROM AUTHOR]

As global energy consumption grows and environmental concerns intensify, the demand for alternative fuels is becoming increasingly significant. This study investigates the properties and effects of isopropanol when added to gasoline as an alternative fuel. The overall analysis focusing on engine performance and emissions shows the impact of isopropanol as a fuel additive. From the results, an improvement in engine efficiency was observed due to isopropanol's high-octane number and improved combustion characteristics when added. There are also disadvantages associated with increased fuel consumption due to the lower energy density. Emissions analysis shows that there is a reduction in hydrocarbon and nitrogen oxide emissions with the addition of isopropanol, although with different trends depending on the concentration. The results of the study present the complex relationship between fuel composition and engine performance, offering insights into the possibility of using isopropanol as an alternative fuel in the search for sustainable energy solutions. The results showed that for this engine, it is most effective to add isopropanol in the range of 5–15%, relative to which emissions are prioritized to be reduced. The lower energy density of isopropanol reduces the overall energy density, which increases fuel consumption to achieve efficiency over gasoline-only operation. [ABSTRACT FROM AUTHOR]

An efficient and versatile synthesis of alcohols via transfer hydrogenation from ketones with isopropanol, utilizing [Ni(6,6′‐(OH)2‐2,2′‐bpy)][Br2] under alkaline conditions, has been documented. It was noteworthy that many readily reducible or labile functional groups such as nitro, cyano, and halide, within the same molecular framework, did not undergo any change under the standard reaction conditions. Furthermore, the gram scale transfer hydrogenation reaction was successfully carried out with good yield using a common route with only a single purification by column chromatography. [ABSTRACT FROM AUTHOR]

Enhancing the sensing properties of resistive sensors holds pivotal importance as a non-invasive technology for identifying lung cancer biomarkers. This study focused on the development of a robust sensing platform to effectively detect low-concentration biomarkers with low concentration. Ti 3 C 2 T x MXene was prepared by HF etching and ZnO was successfully grown on the MXene nano-multilayers via hydrothermal method subsequently. TiO 2 –ZnO samples were obtained after the calcination step. Various characterization methods were applied to validate the structural integrity and formation of the TiO 2 –ZnO n-n heterojunction. The TiO 2 –ZnO sensor with a Ti:Zn atom ratio of 1:1 (TZ1) exhibited special sensing characteristics, which can be attributed to the higher activation energy (89.2 kJ/mol) and the more substantial interfacial contact areas between the two metal oxides. This architectural arrangement gives rise to the creation of numerous energy barriers, effectively hindering electron migration. Despite exhibiting the acceptable response, TZ1 can be applied in electronic nose systems to effectively detect lung cancer indicators with low concentrations (i.e., acetone, formaldehyde, NH 3) in light of its high stability and steady signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

Conversion of isopropanol under supercritical conditions (400 °C, 11.0 MPa) on calcium and magnesium stannates MSnO3 (M = Ca, Mg) was studied. The main direction of the process is dehydrogenation of isopropanol to acetone, which then enters into the aldol condensation with selective formation of isomeric mesityl oxides. Products of hydrogenation of the C=C and C=0 bonds in mesityl oxide as well as products of isopropanol dehydration were also obtained. Under the experimental conditions, isopropanol is both a supercritical solvent and a source of hydrogen for hydrogenation of the multiple bonds. According to the results of diffuse reflectance infrared Fourier transform spectroscopy study using deuterated chloroform as a probe molecule, basic oxygen sites of the catalysts are of medium strength. During the conversion of isopropanol the more active catalyst MgSnO3 completely decomposes into the oxides MgO and SnO2 and the latter is then reduced to metallic tin, while the less active catalyst CaSnO3 is reduced slightly. [ABSTRACT FROM AUTHOR]

Catalytic transfer hydrogenation (CTH) is a green and efficient pathway for selective hydrogenation of unsaturated aldehydes and ketones. However, managing the abilities of solid catalysts to adsorb substrates and to convert them into desired products is a challenging task. Herein, we report the synthesis of carbon coated LaFe0.92Pd0.08O3 composites (LFPO-8@C) for CTH of benzaldehyde (BzH) into benzyl alcohol (BzOH), using isopropanol (IPA) as hydrogen source. The coating with carbon improves the ability to adsorb/transfer reactants from solution to active sites, and the doping of Pd2+ at Fe3+ site strengthens the ability of LaFeO3 to convert BzH into BzOH. A balanced point between them (i.e., abilities to adsorb BzH and to convert BzH into BzOH) is obtained at LFPO-8@C, which exhibits a BzOH formation rate of 3.88 mmol⋅ggat-1⋅h-1 at 180 °C for 3 h, which is 1.50 and 2.72 times faster than those of LFPO-8 and LaFeO3@C. A reaction mechanism is proposed, in which the acidic sites (e.g., Fe4+, oxygen vacancy) are used for the activation of C=O bond of BzH and O–H bond of IPA, and the basic sites (e.g., lattice oxygen) for the activation of α–H (O–H) bond of IPA. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of isopropanol on the optical properties of the Fe₃O₄/ZnO/GQDs nanocomposite. The synthesis of Fe₃O₄ and ZnO nanoparticles was conducted using the coprecipitation method, followed by the synthesis of GQDs using the hydrothermal method with varying concentrations of isopropanol. Subsequently, the Fe₃O₄/ZnO nanocomposite was combined with GQDs synthesized using the sonication method. The amalgamation of magnetic and luminescent materials holds promise for applications in the biomedical field, particularly in bioimaging. XRD data analysis revealed crystal structure alterations attributed to the incorporation of carbon elements in both ZnO and Fe₃O₄. The TEM results indicated a particle size of 16.2 nm for the Fe₃O₄/ZnO/GQDs nanocomposite with a 10 ml isopropanol variation. Identified phases from the XRD analysis include Fe₃O₄, ZnO, and GQDs. UV-Vis spectroscopy detected distinctive absorbance peaks at wavelengths of 323.7 nm, 333.0 nm, 329.9 nm, and 323.9 nm. Moreover, the energy gap exhibited an increase with escalating concentrations of isopropanol in the GQDs. Photoluminescence analysis yielded robust, broad emission bands characterized by orange and red luminescence.

The extractive distillation process using propylene glycol (IUPAC name: 1,2 propanediol) as an extractive agent for the separation of the isopropanol–water system was investigated in this work. A systematic procedure was set out to obtain the optimal design and process conditions for extractive distillation and solvent recovery columns using the PRO/II process simulator. Four thermally integrated flowsheets were proposed, implying the recovery of the sensible heat and latent heat from the hot streams in the process. To establish the economic feasibility of the proposed process, we calculated the total annual cost for all the simulated versions, and the proposed fully thermally integrated flowsheets could save up to 43.13% in terms of the utility costs and up to 15.57% in terms of the TAC compared to the conventional design. Thus, propylene glycol (PG) is found to be suitable as a new solvent for isopropanol dehydration, being comparable with other classical solvents used for the dehydration of alcohols.

A sustainable reversed-phase chromatographic method has been developed and validated for the simultaneous determination of three active pharmaceutical ingredients, dorzolamide, brinzolamide, and timolol, used to treat glaucoma. The eco-friendly solvent isopropanol has been used as an organic mobile phase constituent. According to the Hansen space green solvent selection tool, isopropanol has a G score of 6.5, comparable to ethanol, which has a G score of 6.6. The mobile phase consists of isopropanol: aqueous sodium acetate buffer (0.1 M, pH 4.25) in the ratio of 10:90 (v/v). The flow rate was maintained at 1 mL/min. Dorzolamide and brinzolamide were detected at 254 nm, and timolol was detected at 295 nm. A high-purity silica with a polymeric C18 modification column (150 × 4.6 mm, 5 µm particle size) was used for this separation. The three compounds were eluted within 8 min. The method was validated according to ICH guidelines. The calibration curves were linear in the range of 20–70 µg/mL, 40–140 µg/mL, and 20–70 µg/mL for dorzolamide, brinzolamide, and timolol, respectively. The LODs were found to be 1.61 µg/mL, 1.60 µg/mL, and 3.16 µg/mL for dorzolamide, brinzolamide, and timolol, respectively. Good accuracy and precision were obtained for the three compounds. The greenness and whiteness of the method were indicated using the AGREE, ChlorTox, and RGB12 tools. [ABSTRACT FROM AUTHOR]

The microscopic observation of lung tissue is challenging due to its fragile nature. Xylene and isopropanol are common tissue-clearing reagents used before paraffin embedding, yet no studies have compared these two reagents in lung tissue processing. Due to the well-known health risks xylene could introduce to operators, as well as its environmental hazards, it has long been desired that a less harmful alternative to xylene with the same staining effects be introduced. Thus, we systematically assessed the efficacy of isopropanol as a substitution for xylene. Lung tissue obtained from diseased donors and explanted lungs from recipients were processed simultaneously using either xylene or isopropanol prior to paraffin embedding. Scoring of the overall staining quality after H&E staining, along with the ease of sectioning, was compared systematically. Fluorescent staining was performed to explore alveolar morphology and the overall lectin fluorescence signal between groups. To understand differences in antibody staining, the signal-to-noise ratio (SNR) of smooth muscle actin (SMA) and elastin was examined. No difference was observed with regard to ease of sectioning, staining quality, alveolar circularity, alveolar wall thickness or the SNR between slides processed with xylene or isopropanol. This study demonstrated comparable outcomes of isopropanol and xylene in lung tissue processing, suggesting isopropanol as a more favorable, operator- and environment-friendly substitute for xylene with regards to tissue processing. [ABSTRACT FROM AUTHOR]

Heterogeneous photocatalysis is a promising technology for the abatement of pollutants in the air. Practical application of this technology requires the incorporation of the photocatalyst into a coating formulation. The coating can subsequently be applied on surfaces with a large geometric area, promoting various catalytic reactions. Photocatalysts, such as TiO2, appear to be most active in the form of nanoparticles. However, there is a rising concern regarding the adverse health effects of the nano‐sized particles. In this study, we investigate the photocatalytic oxidation of isopropanol, a common VOC, and demonstrate that a water‐based acrylic coating containing TiO2 micrometer‐sized hollow spheres can outperform a nanoparticle‐based coating by a factor of 10 in the rate of isopropanol removal. The porous shell structure of TiO2 hollow microspheres enables a three‐dimensional surface porosity within the coating film, thereby enhancing the access to the active catalytic surface. Our findings underscore the importance of the catalyst morphology for practical applications of photocatalytic materials when integrated into a coating formulation. [ABSTRACT FROM AUTHOR]

Acetone hydrogenation is employed for investigating the structure sensitivity of H 2 activation over cobalt catalysts while the produced isopropanol garners increasing interest in the sustainable energy context e.g. as H 2 storage material and fuel for direct fuel cells. Both hexagonal close-packed (hcp) and face-centered cubic (fcc) Co can produce isopropanol with 100% selectivity below 150 °C with the reaction proceeding almost ten times faster over hcp Co. Hydrogenation rates are even higher over an hcp Co/Co 3 O 4 composite which remains highly selective to isopropanol despite that Co 3 O 4 yields mostly mesityl oxide and related products. The superior performance of hcp Co and its composite are attributed to efficient generation of atomic H on the metal and the presence of stronger sites for acetone activation on XRD-amorphous phases that are formed during reduction of the Co 3 O 4 precursor at 250 °C and 400 °C. These findings provide insight into the optimum structural design of highly active and selective low-temperature cobalt hydrogenation catalysts. [Display omitted] • XRD-amorphous components in hcp Co and hcp Co/Co 3 O 4 composite catalysts. • Acetone turnover frequencies 3–4 times higher over hcp than fcc Co at 100 °C. • Amorphous phase promotes activity of hcp Co/Co 3 O 4 by another factor 6-8. • 97–100% isopropanol selectivity over hcp Co, fcc Co and hcp Co/Co 3 O 4 below 150 °C. • Reaction path and product selectivity are very sensitive to H 2 activation. [ABSTRACT FROM AUTHOR]

Dehydration of i-PrOH is used in academic research as a test reaction to probe the acid properties of solid acid catalysts. Also, it has practical importance for the utilization of surplus acetone produced by the Hock process for the combined manufacturing of phenol and acetone as well as for the production of propene from renewable resources and waste. This study demonstrates the excellent performance of polyoxometalate acid catalysts comprising silica-supported Keggin-type heteropoly acids H3PW12O40 and H4SiW12O40 for gas-phase i-PrOH-to-propene dehydration at ambient pressure. These catalysts show similar efficacies, giving an i-PrOH conversion and propene selectivity of 96.8 and 99.7% for 25%HPW/SiO2 and 97.1 and 99.4% for 25%HSiW/SiO2 in a fixed-bed reactor at 120 °C, a relevant-to-practice i-PrOH partial pressure of 15 kPa and a contact time W/F = 27 g h mol−1 (GHSV = 900 mL g−1 h−1). The catalysts are stable, resisting deactivation for at least 24 h time on stream. The HPA/SiO2 catalysts are superior to aluminosilicate zeolites such as H-mordenite, HZSM-5 and HY for i-PrOH-to-propene dehydration in terms of i-PrOH conversion, propene selectivity and catalyst stability. [ABSTRACT FROM AUTHOR]

Bimetallic catalysts based on ZSM-5 zeolite modified with ytterbium and nickel have been prepared. The influence of the concentration of ytterbium (1.7-5.0 wt.%) and nickel (1.0-1.5 wt.%) on the acidic, textural and catalytic properties of the zeolite in the reaction of alkylation of toluene with isopropanol in the temperature range of 300-350℃ was studied. It has been shown that the unmodified zeolite HZSM-5 exhibits low selectivity (54.6-58.2%) for isopropyltoluenes (3-IPT, 4-IPT, and 2-IPT) than the modified catalysts. In addition, the content of the valuable 4-IPT isomer does not exceed 44.2%. Modification of HZSM-5 with ytterbium in an amount of 5.0 wt.% leads to an increase in the selectivity for isopropyltoluenes up to 68.7%, and the selectivity for 4-IPT up to 68.8%. Additional modification of the 3%-Yb-HZSM-5 catalyst with nickel in the amount of 1.0 wt.% prevents the formation of 2-IPT and promotes an increase in the yield of 4-IPT. The modified catalysts were characterized by XPA, BET, BJH, and ammonia TPD. Modification, calcination, and successive treatment of the catalyst with air and hydrogen leads to a dispersed distribution of Yb2O3 and metallic nickel oxide nanoparticles in the outer surface and in the pores of the zeolite, which causes a decrease in the specific surface area, total pore volume, and an increase in the fraction of mesopore volume. As a result of the interaction of modifiers with acidic OH groups of the zeolite, the concentration of strong Brønsted acid sites decreases and new, stronger Lewis acid sites form. All this has a decisive effect on the selectivity of 4-IPT formation and the stability of the bimetallic catalyst. The maximum selectivity for 4-IPT on a 3% Yb 1.0% Ni/HZSM-5 bimetallic catalyst is achieved at 3300C and is 71.5% at a toluene conversion of 24.6%. [ABSTRACT FROM AUTHOR]

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As global energy consumption grows and environmental concerns intensify, the demand for alternative fuels is becoming increasingly significant. This study investigates the properties and effects of isopropanol when added to gasoline as an alternative fuel. The overall analysis focusing on engine performance and emissions shows the impact of isopropanol as a fuel additive. From the results, an improvement in engine efficiency was observed due to isopropanol’s high-octane number and improved combustion characteristics when added. There are also disadvantages associated with increased fuel consumption due to the lower energy density. Emissions analysis shows that there is a reduction in hydrocarbon and nitrogen oxide emissions with the addition of isopropanol, although with different trends depending on the concentration. The results of the study present the complex relationship between fuel composition and engine performance, offering insights into the possibility of using isopropanol as an alternative fuel in the search for sustainable energy solutions. The results showed that for this engine, it is most effective to add isopropanol in the range of 5–15%, relative to which emissions are prioritized to be reduced. The lower energy density of isopropanol reduces the overall energy density, which increases fuel consumption to achieve efficiency over gasoline-only operation.

A common issue in studies on liquid-phase chemical processes is that the natural solid nanoimpurities present in reagent-grade chemicals are ignored. Little is known about these impurities’ nature, sizes, concentrations, and behavior, yet they significantly affect the efficiency of antiscalants in municipal and laboratory solutions. Recent research has focused on: (i) estimating nanoimpurity concentrations in in-house deionized water and semiconductor-grade isopropanol using “light sheet” optical ultramicroscopy, and (ii) visualizing antiscalant sorption on these impurities. Using a fluorescent-tagged antiscalant aminobis(methylenephosphonic acid) (ADMP-F), we tracked its affinity to particulate matter in deionized water and reagent-grade KCl solutions. Our study showed that the total concentration of nanoparticles with a size larger than 20 nm is about 106 units/mL in deionized water and 105 units/mL in isopropanol. Extrapolation of these values to a size ≥1 nm resulted in concentrations of 1011 and 108 units/mL. The addition of KCl or ADMP-F significantly increased foreign nanoparticle populations. ADMP-F is selectively adsorbed by only some impurities, while most antiscalant molecules remain as true solution. To our knowledge, this is the first instance of fluorescently labeled aminoalkylphosphonates being able to differentiate particulate matter traces in reagent-grade purity solutions. Therefore, the role of nanoparticles as crystallization centers should be seriously reconsidered, especially in their important application in scale inhibition.

The performance of a new commercial polyvinyl alcohol (PVA) membrane (PERVAPTM 4100HF) was investigated and compared with a standard membrane (PERVAPTM 4100) for the dehydration of isopropanol (isopropyl alcohol) with an azeotropic point using pervaporation process. Both membranes were also characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and contact angle (CA) goniometer. The results showed that the PERVAP™ 4100HF was thinner (1–1.5 μm) and had a lower degree of cross-linking than the PERVAP™ 4100HF (2–3 μm). The effect of the feed water concentration and operating temperature on the membranes separation performance in terms of the permeation flux, separation factor, selectivity, and permeance was investigated. The water permeates in the PERVAP™ 4100HF (∼3350 GPU) was seven times higher than that in PERVAP™ 4100 (∼463 GPU) at 70 °C and for 7 wt.% of water concentration in the feed. The water/isopropanol selectivity of the new membrane under these operating conditions was very high (∼17,000). The total permeation flux of water and isopropyl alcohol (IPA) was increased with the feedwater concentration (0.0690–1.0275 and 0.0079–0.6384 kg/m2.hr) for PERVAP™ 4100HF and PERVAP™ 4100, respectively with feed water concentration increased from 7 to 18 wt.%. The temperature dependence of the pervaporation behaviors was investigated in detail in terms of the Arrhenius activation energy. The effect of the feedwater concentration on the Arrhenius activation energy was also studied to evaluate the mass transfer across the membrane under other operating conditions, such as high temperatures and low feedwater concentrations. The new membrane PERVAP™ 4100HF exhibited the best dehydration properties at water concentrations in the azeotropic region and below, making it possible to pervaporate even at low feedwater concentrations.

The results of a study of tandem reactions - aldol-crotonic condensation and hydrogenation by the mechanism of hydride transfer in acetone-isopropanol mixtures on a МgSnО3 catalyst at 300–400°C and 12.0 MРa are presented. In these conditions the mixture of reactants (acetone and isopropanol) and reaction products is in supercritical state. The temperature dependences of the reactants conversion and the selectivity for condensation and hydrogenation products are considered. It has been established that the hydrogenation of acetone aldol-crotonic condensation products proceeds by the addition of hydrogen from isopropanol molecule to C=O-bonds of isomeric mesityl and phorone oxides and is accompanied by dehydration of alcohols and isomerization of double C=C-bonds. The optimal conditions for the formation of the carbonyl group hydrogenation products are 350°C and the ratio acetone : isopropanol = 7 : 3. At the acetone to isopropanol ratio 1 : 1, methylpentadienes dominate in the products of mesityl oxide conversion. The hydrogenation reaction also proceeds with the participation of isophorones, the condensation products of three acetone molecules. [ABSTRACT FROM AUTHOR]

Oil Red O (ORO) staining is a commonly used experimental technique to detect lipid content in cells or tissues. Freshly prepared ORO in 60% isopropanol is the most widely used method at present. However, isopropanol is volatile and harmful to the human body. It will also affect the interpretation of the results due to the formation of crystals and non-specific diffuse staining. In this paper, by screening and validation, we report a salicylic acid ethanol solution (containing 50% ethanol, 5%-10% salicylic acid) for the preparation of ORO solution, which has a better staining effect on lipid staining in cells and tissues, with a clean background and short dyeing time. What's more, this ORO solution is non-toxic, convenient to prepare, and can be stored for a long time. Therefore, it is reliable, easy to operate, and can be widely popularized and applied in laboratories. [ABSTRACT FROM AUTHOR]

Graphene aerogel are frequently employed as electrode materials for power batteries due to their high specific surface area and excellent properties. This paper presents a method for preparing graphene aerogel by radiolytic reduction in a water and isopropanol system. In this study, the authors used radiolytic reduction technology to reduce graphene oxide to graphene aerogel and investigated the effects of various factors in the water and isopropanol system on its preparation process and properties. The experimental results showed that the water and isopropanol system could effectively prepare graphene aerogel with a high specific surface area, and the isopropanol concentration and irradiation time in the isopropanol system had important effects on its properties. This preparation method has the advantages of simplicity, rapidity, and low cost, providing a new idea for the large-scale preparation of graphene aerogel. [ABSTRACT FROM AUTHOR]

The depletion of fossil fuel resources and the CO2 emissions coupled with petroleum-based industrial processes present a relevant issue for the whole of society. An alternative to the fossil-based production of chemicals is microbial fermentation using acetogens. Acetogenic bacteria are able to metabolize CO or CO2 (+H2) via the Wood–Ljungdahl pathway. As isopropanol is widely used in a variety of industrial branches, it is advantageous to find a fossil-independent production process. In this study, Acetobacterium woodii was employed to produce isopropanol via plasmid-based expression of the enzymes thiolase A, CoA-transferase, acetoacetate decarboxylase and secondary alcohol dehydrogenase. An examination of the enzymes originating from different organisms led to a maximum isopropanol production of 5.64 ± 1.08 mM using CO2 + H2 as the carbon and energy source. To this end, the genes thlA (encoding thiolase A) and ctfA/ctfB (encoding CoA-transferase) of Clostridium scatologenes, adc (encoding acetoacetate decarboxylase) originating from C. acetobutylicum and sadH (encoding secondary alcohol dehydrogenase) of C. beijerinckii DSM 6423 were employed. Since bottlenecks in the isopropanol production pathway are known, optimization of the strain was investigated, resulting in a 2.5-fold increase in isopropanol concentration. [ABSTRACT FROM AUTHOR]

The catalytic dehydrogenation of isopropanol is an important area of the catalytic process to produce fine chemicals and has important applications in heat pumps, fuel cells, and acetone production. Thereby, the catalytic liquid-phase dehydrogenation of isopropanol has gained attention over the last decades and has used a large variety of homogeneous and heterogeneous catalysts. In this paper, nickel nitride (Ni3N) nanoparticles, having a cubic structure, were successfully synthesized in simple and efficient methods either from nickel oxide or from nickel complex. The morphological and structural analyses of the obtained nanoparticles were performed by using powder X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX). At room temperature and under atmospheric pressure, the dehydrogenation test of isopropanol, using nickel nitride as a catalyst, revealed very high activity and better Hydrogen production. • New Nickel nitride was used for the dehydrogenation of isopropanol. • Preparation methods are simple, effective, and less expensive. • Morphological and structural analyses of the new materials have been performed. • Catalytic dehydrogenation test of isopropanol has shown very good results. [ABSTRACT FROM AUTHOR]

Propanol isomers, which are oxygen-rich fuels, possess superior octane ratings and energy density in comparison to methanol and ethanol. Recently, due to advancements in fermentation techniques, these propanol isomers have garnered increased interest as additives for engines. They are being explored to decrease emissions and reduce the usage of conventional fossil fuels. This study delves into this emerging field. One of the alternatives is the use of alcohol fuels in their pure state or as additives to traditional fuels. Alcohols, due to their higher volumetric energy density, are better fuels for spark ignition engines than hydrogen and biogas. Alcohol-blended fuels or alcohol fuels in their pure state may be used in gasoline engines to reduce exhaust emissions. The current research emphasizes the effect of isopropanol gasoline blends on the performance and emissions characteristics of a gasoline direct injection (GDI) engine. This investigation was conducted with different blends of isopropanol and gasoline (by volume: 10% isopropanol [IP10], 20% isopropanol [IP10], 30% isopropanol [IP30], 40% isopropanol [IP40], and 50% isopropanol [IP50]). The reviewed results showed that with increasing isopropanol in the fuel blends, engine brake power increased while BSFC decreased. In terms of emissions, with the increase in isopropanol in the fuel blends, CO and HC emissions decreased while CO2 and NOx emissions increased. [ABSTRACT FROM AUTHOR]

Lanthanide catalysts are used in the industrial production of stereoregular rubbers. It is believed that the activity of solvate complexes of lanthanide chlorides increases with decreasing size of their particles and increasing content of the solvating ligand. The kinetics of isoprene polymerization catalyzed by the isopropanol solvates of gadolinium chloride GdCl3·n(i-PrOH), which were obtained by various methods (conventional mechanical stirring, hydrodynamic exposure, ultrasonic irradiation), was studied. A correlation between the particle size and composition of the solvate complex and the activity of the catalyst was found whatever the method the solvate complex was obtained. At the same time, the resulting data show that, at comparable particle size and composition of the complex, its activity in the polymerization of isoprene nevertheless depends on the method of synthesis. It was shown that the gadolinium catalysts exhibit the highest activity in isoprene polymerization, when the solvate complexes are subjected to hydrodynamic treatment after preliminary solvation for 4–8 h. [ABSTRACT FROM AUTHOR]

We investigate the aggregative stability of Ag/PVP nanoparticles (0.1 and 0.3 wt% of Ag) in colloidal solutions, based on isopropanol, water, and a propylene glycol-water mixture, promising for the application as secondary coolants. The solutions were found to be stable for at least six months. The development of methods for synthesizing nanofluids is promising for intensifying heat and mass exchange, as well as for modifying the thermophysical properties of secondary coolants. [ABSTRACT FROM AUTHOR]

Vapor–liquid equilibrium data of binary systems (water + acetic acid, isopropanol + water, and acetic acid + isopropyl acetate), and ternary systems (water + acetic acid + 1-sulfobutyl-3-methylimidazolium hydrogen sulfate (ionic liquid, [HSO3-bmim][HSO4]), isopropanol + water + [HSO3-bmim][HSO4], and acetic acid + isopropyl acetate + [HSO3-bmim][HSO4]) were determined at 101.33 kPa. The nonrandom two-liquid (NRTL) model fitted well with the experimental data. The σ-profiles of water, acetic acid, isopropanol, isopropyl acetate, [HSO3-bmim]+, and [HSO4]− were calculated using the COSMO-RS model. Furthermore, the binding abilities of [HSO3-bmim][HSO4] ionic liquid with water, acetic acid, isopropanol, and isopropyl acetate were analyzed by σ-profiles. The chemical and phase equilibrium data of acetic acid + isopropanol, and acetic acid + isopropanol + [HSO3-bmim][HSO4] systems were determined, meanwhile, the chemical equilibrium constant Kr was calculated. These results provided basic thermodynamic data for [HSO3-bmim][HSO4] as the catalyst for the esterification system of acetic acid with isopropanol. [ABSTRACT FROM AUTHOR]

In this study, SDS is used to enhance the sulfuric acid leaching of chalcopyrite in aqueous and isopropanol media. The presence of SDS increased copper extraction into the solution in both solvents. However, it was the "isopropanol–sulfuric acid–SDS" system that proved to be particularly effective for copper recovery from chalcopyrite. The positive effect of SDS can be attributed to the reduction in the solution's surface tension and the enhancement of mineral wetting. Additionally, the presence of SDS as a surfactant induces changes in the adsorption patterns of formed sulfur species on the mineral surface. SDS competes with sulfur for occupancy on the surface binding sites. This competitive interaction has the potential to diminish the formation of a substantial sulfur layer on the mineral surface. Under optimal conditions (isopropanol media, 2 M H2SO4, 65 °C, 120 min, 0.6 g/L SDS), copper recovery into the solution was 83%, and this is a considerable achievement for chalcopyrite leaching at ambient pressure in the absence of strong oxidizers. [ABSTRACT FROM AUTHOR]

The use of water–ethanol mixtures in hot pressurized liquid extraction (HPLE) to recover phenolic compounds from agro-industrial waste has been successfully investigated. However, the unresolved challenge of reducing solvent costs associated with the process hinders the scaling of this eco-friendly technology. This study evaluated the use of isopropanol as an alternative, lower-cost solvent for recovering polyphenols from discarded blueberries through the HPLE process. HPLE was carried out using water–isopropanol mixtures (0, 15 and 30%) at 70, 100, and 130 °C. The total polyphenol content (TPC), antioxidant capacity (DPPH and ORAC), glucose and fructose contents, and polyphenol profile of the extracts were determined. HPLE extracts obtained using high isopropanol concentrations (30%) and high temperatures (130 °C) presented the highest TPC (13.57 mg GAE/gdw) and antioxidant capacity (IC50: 9.97 mg/mL, ORAC: 246.47 µmol ET/gdw). Moreover, the use of 30% water–isopropanol resulted in higher yields of polyphenols and removal of reducing sugars compared to atmospheric extraction with water–acetone (60%). The polyphenolic profiles of the extracts showed that flavanols and phenolic acids were more soluble at high concentrations of isopropanol (30%). Contrarily, flavonols and stilbenes were better recovered with 15% isopropanol and pure water. Therefore, isopropanol could be a promising solvent for the selective recovery of different bioactive compounds from discarded blueberries and other agro-industrial residues. [ABSTRACT FROM AUTHOR]

This work presents the first development of an analytical turbidimetric method for the determination of legal alcohols in alcohol-based hand sanitizer products. A typical iodoform reaction is exploited to form a yellow product in the form of precipitates. An iodoform test shows a positive result as yellow precipitates in the presence of ethanol and isopropanol; therefore, the test can only be used to distinguish between methanol and those legal alcohols. In the presence of molecular iodine (I2) and a strong alkaline solution, the legal alcohol is converted to the corresponding carbonyl compound (i.e., ethanol to acetaldehyde, isopropanol to acetone). The susceptibility of this intermediate towards the reaction with hydroxide ions (strong alkaline condition) results in formations of yellow precipitation of iodoform (CHI3) and a water-soluble carboxylate salt in the solution. Therefore, this change allows for the detection of legal alcohols through either naked-eye observation (as semi-quantitative analysis) or a common benchtop/portable photometer/spectrophotometer (as quantitative analysis) by means of turbidimetric analysis. In this work, turbidimetry is employed, which is a useful alternative detection method in analytical practice, especially with colored samples in hand sanitizing products. This is because they can employ wavelengths at which the colored solution does not absorb light. As a result of our developed method, the calibration plots are in the range of 30 to 100% (v/v) for both ethanol and isopropanol. The limit of detection (LOD) (3SD of y-intercept/slope) was found to be 7.4% (v/v) ethanol and 6.5% (v/v) isopropanol. Direct analysis of the non-pretreatment of the sample is achieved. The results indicate that our new proposed analytical method is fit for purpose and valid to detect the legal alcohols in alcohol-based hand sanitizing products for both international and Thai regulations (at least 70% (v/v)). Our quantitative results were also comparable to a standard analytical method, such as the use of a gas chromatography-flame ionization detector (GC-FID). Our developed method and analytical operation could potentially be developed into a practically portable analysis.

This study investigates the effect of synthesis methods on the physicochemical properties and catalytic activity of α-MnO2 catalysts in the complete oxidation of isopropanol. The catalysts were synthesized via redox-precipitation reactions by using dropwise and reflux methods and characterized by XRD, SEM, and N2 adsorption-desorption. The results show that the synthesis methods significantly effect on the properties and catalytic activity of α-MnO2 catalysts. The dropwise method facilitates the formation of α-MnO2 nanofibers with lower crystallite size (12 nm), higher surface area (68 m2/g), and pore volume (0.16 cm3/g), which enhance the complete oxidation performance in comparison with α-MnO2 nanorods synthesized by the reflux method. Over α-MnO2 nanofibers, the T50(CO2) and T90(CO2) temperatures, at which 50% and 90% of isopropanol are converted to CO2, were found to be 155 °C and 166 °C, respectively.

Background: Current threats connected to the ongoing depletion of fossil resources and elevated levels of greenhouse gases accelerating climate change and global warming provoke a renaissance of biotechnological production of various organic bulk chemicals, which, particularly during the second half of the 20th century, were almost exclusively produced from fossil resources via chemosynthetic processes.

ABSTRACTOil Red O (ORO) staining is a commonly used experimental technique to detect lipid content in cells or tissues. Freshly prepared ORO in 60% isopropanol is the most widely used method at present. However, isopropanol is volatile and harmful to the human body. It will also affect the interpretation of the results due to the formation of crystals and non-specific diffuse staining. In this paper, by screening and validation, we report a salicylic acid ethanol solution (containing 50% ethanol, 5%-10% salicylic acid) for the preparation of ORO solution, which has a better staining effect on lipid staining in cells and tissues, with a clean background and short dyeing time. What’s more, this ORO solution is non-toxic, convenient to prepare, and can be stored for a long time. Therefore, it is reliable, easy to operate, and can be widely popularized and applied in laboratories.