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Results for “ISOPROPYL ALCOHOL”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Effects of water on the kinetics of acetone hydrogenation over Pt and Ru catalysts

We employed an approach combining reaction kinetics measurements at steady state conditions, electronic structure calculations employing density functional theory, and microkinetic modeling for acetone hydrogenation to provide insights into the effects of water on metal catalyst surfaces for the hydrogenation of oxygenates over a wide range of reaction conditions. Elucidation of the repulsive interactions due to adsorbed water molecules at various reaction conditions provides a basis to formulate rate expressions for heterogeneous catalytic processes of biomass oxygenates. Reaction kinetics experiments were carried out at partial pressures of H 2 , acetone, water and helium in the range of 0.51-0.79, 0.02-0.13, 0.08-0.23, 0-0.28 atm, respectively. We show that the addition of water enhances the hydrogenation rate at 353 K and 1 atm on oxophilic metal catalysts such as Ru/C, whereas the same promotional effect of water is not observed for Pt-based catalysts. Microkinetic model predictions for the hydrogenation of acetone on Ru in the absence and presence of water, using enthalpies and entropies obtained from DFT calculations, were in agreement with the experimentally observed reaction orders and activation barriers. The model shows that a water-assisted hydroxypropyl path is expected to be the favored path on Ru with a rate-determining step of H-OH-mediated hydrogenation of C 3 H 6 OH (i.e., the hydroxypropyl intermediate formed by H 2 O-mediated initial hydrogenation of acetone) to produce isopropyl alcohol (IPA). Furthermore, hydrogen, acetone, hydroxypropyl intermediate and hydroxyl species were predicted to be abundant on the Ru surface with a high coverage of nearly 85%. Lastly, the combined studies of computational and experimental catalysis on hydrogenation reactions help to elucidate the mechanistic role of water on metal catalyzed reactions for producing chemical building blocks from biomass-derived oxygenates.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Separation of volatile organic contaminants from water using a direct-contact dehumidifier: An experimental study and modeling

A packed-bed, direct-contact dehumidifier (PB-DCD) has been developed to selectively condense water from a gaseous mixture of organic contaminants. In this process, hot air is humidified by mixing with wastewater vapor in a static mixer and is dehumidified by subcooled fresh water passing through the PB-DCD in a counter-current configuration. The goal of this study is to understand the relationship between various operating parameters and how they affect separation of isopropyl alcohol (IPA) from the gaseous mixture with the purpose of expanding the investigation to other contaminants in the future. The process has been successfully used to separate IPA from wastewater. Different parameters including the concentration of IPA in water, feed temperature, air-to-vapor ratio, and cooling-water-to-vapor mass ratio, as well as residence time were examined to determine their influence on contaminant separation and clean water recovery rate. The Buckingham Pi theorem was applied to reduce the number of studying variables by generating non-dimensional groups. Experiments were performed to determine the relationship between the non-dimensional parameters and model mass transfer in the system. Mass transfer coefficients for multicomponent gaseous mixture condensation in a packed-bed direct contact condenser column are calculated and a modified correlation of mass transfer is developed. The parameters of the mass transfer model are obtained from operating conditions of the PB-DCD, stream conditions and thermodynamic properties. A modified Sherwood correlation is developed to predict IPA separation from a gaseous mixture consisting of air, water, and IPA. The modified Sherwood correlation is applied to successfully predict the Sherwood number with a mean absolute error equal to 6.6 %. According to the experimental results, the maximum IPA separation achieved was 76.3 %, which corresponds to a water recovery rate of 58.7 %.

42 ENGINEERING↗
DOE OSTI2023

On electron beam-induced degradation of vinyl ester thermosets

We have demonstrated that electron beam radiolysis induces scissions of the C-O-C bonds along the backbone of the chains of unsaturated polyester thermosets of different compositions based on dicyclopentadiene, isophthalic acid, epoxy vinyl ester, and terephthalic acid. The radiolysis is imminent irrespective of the degree of crosslinking in the thermosets both in neat resins and in the presence of solvents. Electron Paramagnetic Resonance (EPR) results show the formation of the alkoxyl radicals and C-centered radicals as the primary intermediate products of the C-O-C scissions. While the alkoxyl radicals of these resins exhibit very good stability even six months after the irradiation, the C-centered radicals decay very rapidly via their reactions with oxygen that is available either as adsorbed in the resins, dissolved in solvents or from the environment. The radiolytically produced •OH radicals in the unsaturated-ester aqueous solutions play a major role in inducing scissions on the backbone of the polymer chains. The solvated electrons (e s ) from organic solvents, such as dimethyl sulfoxide and isopropyl alcohol, also induce direct scission of the C-O-C bonds, giving rise to the formation of alkoxyl radicals and C-centered radicals. However, a considerable fraction of es is scavenged by the dissolved O 2 to produce O 2 - . Despite the radiation-induced scissions, irradiation of the resins at a dose level of 1000 kGy results in an increase of the glass transition temperature, Tg. This is due to the simultaneous radiation-induced polymerization of the vinyl monomers, toluene, and styrene that are present in the resins. The increase in Tg is observed in all the resins except for the terephthalic polyester resin in aqueous solution, in which the absence of these monomers results in Tg decreasing sharply with irradiation. This work demonstrates that ionizing radiation triggers continuous free radical-chain reactions that lead to the formation of recyclable oligomers.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2026

Mechanism of Vapor-Phase Infiltration of Organometallic Hf in Poly(Methyl Methacrylate) for Hybrid Resist Applications

Inorganic–organic hybrid thin films synthesized by vapor-phase infiltration (VPI) of metal oxides into organic photoresists, such as poly(methyl methacrylate) (PMMA), have recently demonstrated their utility in extreme ultraviolet lithography, critical for angstrom-era semiconductor device miniaturization. Hafnium oxide infiltration has been reported recently for this purpose, but its detailed VPI mechanism has remained largely unexplored. In this study, we investigated the VPI characteristics and mechanisms of tetrakis(dimethylamido)hafnium (TDMAHf)─the hafnium precursor predominantly used for VPI in the field─into PMMA and examined its impact on electron-beam lithography (EBL) exposure behavior. VPI was performed at temperatures ranging from 85 to 150 °C, with chemical interactions characterized using infrared reflection-absorption spectroscopy, and resist patterning performance was evaluated through EBL dose-sensitivity assessments. The results indicate that TDMAHf forms a reversible adduct with PMMA at temperatures up to 120 °C, whereas at 150 °C, covalent bond formation occurs, most likely via dealkylation that leads to acetate formation. EBL studies reveal that resist sensitivity is influenced by both infiltration temperature and developer selection, with aqueous isopropyl alcohol development demonstrating enhanced sensitivity compared to organic solvent-based development. The optimized infiltration protocol at 120 °C ensures a uniform inorganic distribution without compromising resist dissolution. These findings not only help refine hybrid resist patterning performance but also offer insights potentially applicable to the VPI of other homoleptic metal-amide organometallic VPI precursors that include TDMA ligands.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Preventing Loss of Selectivity during the Oxidative Dehydrogenation of Propane over Supported Vanadium Catalysts

Supported vanadium materials are promising catalysts for the oxidative dehydrogenation of propane to propylene (ODHP), but a lack of mechanistic understanding limits the rational design of catalysts with improved propylene selectivity. Adding Ta to V/SiO 2 increases the propylene selectivity, as well as the activity, leading to superior performance compared to state-of-the-art boron-based systems. In this contribution, we utilize this surprising promotional effect of Ta to elucidate key elements of the mechanistic cycle. Through a combination of characterization techniques, computational modeling, and kinetic experiments, we show that the catalytic cycle over V/SiO 2 likely involves the formation of an isopropyl alcohol intermediate, the fate of which is in kinetic competition between subsequent dehydration to propylene or further oxidation. Furthermore, we show that the relatively facile propylene overoxidation observed for these materials occurs via the epoxidation of propylene by a proposed peroxovanadium intermediate, rather than the abstraction of propylene’s allylic C–H bond as previously assumed. Using these key mechanistic features, we rationalize the enhanced selectivity and activity of Ta promotion. In conclusion, our mechanistic framework offers avenues for future catalyst development to improve supported vanadium materials for ODHP.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Charge-Density-Wave Thin-Film Devices Printed with Chemically Exfoliated 1T-TaS 2 Ink

In this work, we report on the preparation of inks containing fillers derived from quasi-two-dimensional charge-density-wave materials, their application for inkjet printing, and the evaluation of their electronic properties in printed thin-film form. The inks were prepared by liquid-phase exfoliation of CVT-grown 1T-TaS 2 crystals to produce fillers with nm-scale thickness and μm-scale lateral dimensions. Exfoliated 1T-TaS 2 was dispersed in a mixture of isopropyl alcohol and ethylene glycol to allow fine-tuning of filler particles thermophysical properties for inkjet printing. The temperature-dependent electrical and current fluctuation measurements of printed thin films demonstrated that the charge-density-wave properties of 1T-TaS 2 are preserved after processing. The functionality of the printed thin-film devices can be defined by the nearly commensurate to the commensurate charge-density-wave phase transition of individual exfoliated 1T-TaS 2 filler particles rather than by electron-hopping transport between them. The obtained results are important for the development of printed electronics with diverse functionality achieved by the incorporation of quasi-two-dimensional van der Waals quantum materials.

1T-TaS2↗
DOE OSTI2021

Surface Reconstruction of Halide Perovskites During Post-treatment

Postfabrication surface treatment strategies have been instrumental to the stability and performance improvements of halide perovskite photovoltaics in recent years. However, a consensus understanding of the complex reconstruction processes occurring at the surface is still lacking. Here, we combined complementary surface-sensitive and depth-resolved techniques to investigate the mechanistic reconstruction of the perovskite surface at the microscale level. We observed a reconstruction toward a more PbI 2 -rich top surface induced by the commonly used solvent isopropyl alcohol (IPA). We discuss several implications of this reconstruction on the surface thermodynamics and energetics. Particularly, our observations suggest that IPA assists in the adsorption process of organic ammonium salts to the surface to enhance their defect passivation effects.

14 SOLAR ENERGY↗
DOE OSTI2025

Sustainable potassium sorbate production from triacetic acid lactone in food-grade solvents

This study advances the production of potassium sorbate (KS) from triacetic acid lactone (TAL) utilizing food-grade solvents, ethanol (EtOH) and isopropyl alcohol (IPA). Here, we have previously demonstrated the route to produce KS from TAL in tetrahydrofuran (THF) as the main solvent, but the use of THF is associated with environmental and health risks especially for food applications. The process employs a catalytic approach in food-grade solvents and includes three main steps: hydrogenation, etherification and hydrolysis, and ring-opening hydrolysis to produce KS from TAL. In the synthesis of KS from TAL, the use of IPA leads to higher yields and reduced reaction times compared to EtOH. As a result, the overall reaction time in IPA was reduced to 35.7 h, compared to 42.1 h in our previous study using THF and EtOH, while achieving a comparable KS yield of 84% from TAL. The synthesized KS exhibits a trans-2, trans-4 geometrical configuration, identical to that of commercially available KS. Through techno-economic analysis (TEA) and life cycle assessment (LCA), we estimated full-scale production of KS from sugarcane with the developed process in IPA could achieve a minimum product selling price (MPSP) of $\$8.27$ per kg with a range of $\$7.06$–10.16 per kg [5th–95th percentiles from 6000 Monte Carlo simulations] and a carbon intensity (CI) of 13.7 [9.6–18.6] kg CO 2 -eq per kg. This study highlights the synthesis of KS from TAL using food-grade solvents, demonstrating improved economic viability and environmental sustainability compared to our previous research (MPSP of $\$9.68$ per kg [$\$8.47$–11.45 per kg] and CI of 16.2 [12.0–21.2] kg CO 2 -eq per kg), as the total required reaction decreases while achieving the comparable overall yield of KS from TAL.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Data for "Sustainable Potassium Sorbate Production from Triacetic Acid Lactone in Food-Grade Solvents"

This study advances the production of potassium sorbate (KS) from triacetic acid lactone (TAL) utilizing food-grade solvents, ethanol (EtOH) and isopropyl alcohol (IPA). We have previously demonstrated the route to produce KS from TAL in tetrahydrofuran (THF) as the main solvent, but the use of THF is associated with environmental and health risks especially for food applications. The process employs a catalytic approach in food-grade solvents and includes three main steps: hydrogenation, etherification and hydrolysis, and ring-opening hydrolysis to produce KS from TAL. In the synthesis of KS from TAL, the use of IPA leads to higher yields and reduced reaction times compared to EtOH. As a result, the overall reaction time in IPA was reduced to 35.7 h, compared to 42.1 h in our previous study using THF and EtOH, while achieving a comparable KS yield of 84% from TAL. The synthesized KS exhibits a trans-2, trans-4 geometrical configuration, identical to that of commercially available KS. Through techno-economic analysis (TEA) and life cycle assessment (LCA), we estimated full-scale production of KS from sugarcane with the developed process in IPA could achieve a minimum product selling price (MPSP) of $8.27 per kg with a range of $7.06–10.16 per kg [5th–95th percentiles from 6000 Monte Carlo simulations] and a carbon intensity (CI) of 13.7 [9.6–18.6] kg CO2-eq per kg. This study highlights the synthesis of KS from TAL using food-grade solvents, demonstrating improved economic viability and environmental sustainability compared to our previous research (MPSP of $9.68 per kg [$8.47–11.45 per kg] and CI of 16.2 [12.0–21.2] kg CO2-eq per kg), as the total required reaction decreases while achieving the comparable overall yield of KS from TAL.

bioproducts↗
DOE OSTI2022

Performance and electret charge of N95 respirators after decontamination [Slides]

Filtration, pressure drop and quantitative fit of N95 respirators were robust to several decontamination methods including vaporous hydrogen peroxide, wet heat, bleach, and ultraviolet light. Bleach may not have penetrated the hydrophobic outer layers of the N95 respirator. Isopropyl alcohol and detergent both severely degraded the electrostatic charge of the electret filtration layer. First data in N95 respirators that the loss of filtration efficiency was directly correlated with loss of surface potential on the filtration layer. The pressure drop was unchanged, so loss of filtration efficacy would not be apparent during a user seal check. Mechanical straps degrade with repeated mechanical cycling during extended use. Decontamination did not appear to degrade the elastic straps. Significant loss of strap elasticity would be apparent during a user negative pressure seal check.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Nanosecond Laser Drying in Wafer Foundries for Significant Energy Efficiency Improvement

Surface drying is a critical process in microelectronics wafer fabrication. In order to reduce and eliminate watermarks, many surface drying processes have been studied and used. Most of the wafer foundries currently use drying processes based on Isopropyl Alcohol (IPA), which causes serious safety (fire), health, environmental, and energy efficiency issues. The long-term goal of this project is to develop a fast, effective, chemical-free, and extremely energy efficient wafer drying technology that employs nanosecond laser-induced sub-surface evaporation and explosion. The objectives of this project are to 1) experimentally develop and verify the laser surface drying method, explore and identify how and to what extent various physical parameters influence the drying efficiency and effectiveness; and 2) understand and optimize the underlying thermodynamics in the proposed laser surface drying, including micro/nanoscale sub-surface superheating, evaporation, explosion, and photo/thermochemical bond breaking via atomistic modeling and experimental characterization. Toward these objectives, five tasks have been accomplished successfully, including 1) develop in-lab laser surface drying setup and study the effect of varied laser parameters, 2) use multiscale hybrid-modeling to study and understand the physics of water behavior during drying toward process optimization, 3) investigate the effect of drying conditions on the drying effectiveness, 4) develop a large-scale laser drying scanning system with automatic scanning, and 5) conduct large-scale simulation to study the effect of dopant level and develop strategies for system development toward industry deployment.

42 ENGINEERING↗
DOE OSTI2023

Understanding Biases in Sample Preparation Techniques for Coupled Scanning Electron Microscopy and MAMA PuO 2 Morphological Analysis

In this project, the scanning electron microscopy (SEM) sampling method used during the statistical design study (SDS) was investigated to determine if any sampling biases were present in the analyzed data. Using standard particle size distribution powders from the National Institute of Standards and Technology (NIST 1984 standard reference material) with the origin wet dispersion method, it was determined that a bias to smaller particles was present. This was supported by theoretical calculations using Stokes’ law to determine the settling rate of spherical particles of roughly the same size and mass as those found in the SDS. Based on the theoretical calculations, it was determined that the settling rate for each of the 76 powder sets in the SDS could be unique based on specific particle shape and mass distributions, making a universal correction factor/formula not applicable. Therefore, priority shifted to developing an improved wet dispersion method that significantly reduced the particle settling rate for all particle size and shapes. This was achieved by replacing the original solvent (isopropyl alcohol) with a heavy liquid (lithium heteropolytungstates), which dramatically slowed the settling rate and allowed for the capture of a suitable homogeneous aliquot. SEM imaging and Morphological Analysis for Material Attribution (MAMA) software analysis were conducted on the NIST standard, and the SEM/MAMA data were compared to data captured by a dynamic image analysis particle size analyzer. The resulting data confirmed that the new wet dispersion method does indeed deliver an improved representative aliquot to the SEM stub. For instance, in the NIST certificate, the average particle size is ~17.1 µm ± 2.2 µm with a normal distribution. The initial wet dispersion method resulted in a drastically reduced average particle size of 6.1 µm in addition to a non-representative heavy bi-modal distribution whereas the improved LST wet dispersion method resulting in an average particle size that was much closer to the NIST certificate (12.7 µm) with a similar normal distribution. Although the improved method was still short of the NIST certificate average, atomic force microscopy analysis determined that the resulting ~20-25% reduction in size was due to particles sinking into the carbon sticky tape used for SEM imaging. It is believed that that this bias can be calibrated in a much more predicable manner than the original settling rate bias. In addition, the matching normal distribution curves between the NIST certificate and the heavy liquid method indicate a much-improved representative aliquot has been sampled and imaged. A surrogate CeO 2 powder was used to reflect PuO 2 more accurately and to aid in implementing radiological controls and shielding. The resulting data sets from the SEM/MAMA method and the particle size analyzer give almost identical average particle sizes and particle distribution statistics. Future work will re-analyze several select runs from the SDS to determine if morphological signatures can be found with the improved sampling method.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

On the Mechanism of the Steady-State Gamma Radiolysis-Induced Scissions of the Phenyl-Vinyl Polyester-Based Resins

The major societal problem of polymeric waste necessitates new approaches to break down especially challenging discarded waste streams. Gamma radiation was utilized in conjunction with varying solvent environments in an attempt to discern the efficacy of radiolysis as a tool for the deliberate degradation of model network polyesters. Our EPR results demonstrated that gamma radiolysis of neat resin and in the presence of four widely used solvents induces glycosidic scissions on the backbone of the polyester chains. EPR results clearly show the formation of alkoxy radicals and C-centered radicals as primary intermediate radiolytic products. Despite the protective role of the phenyl groups on the backbone of the radiation-induced polyester chains, the radiolytic-glycosidic scissions predominate. Among the following three solvents used in this study (water, isopropyl alcohol, and dichloromethane), the highest radiolytic yield of glycosidic scission was achieved using water. The •OH radicals produced in the radiolysis of phenyl unsaturated polyester aqueous suspensions very rapidly abstract H atoms from the methylene group, which is followed by a very rapid glycosidic scission. The lowest glycosidic yield was found in the dichloromethane solutions of these polyester resins due to scavenging by the fast electron capture reactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

The Effect of Adsorbed Volatile Organic Compounds on an Ultrathin Water Film Measurement

Using surface plasmon resonance imaging (SPRi), we have recently shown for the first time the existence of a monolayer water film between droplets during dropwise condensation. This study examines the effect of adsorbed volatile organic compounds (VOCs) on the ultrathin film measurement using SPRi. Further, the work presents the proper surface-treatment process that enables measurements of the ultrathin water layer during high-speed imaging of dropwise condensation at 3000 frame per second. In this study, two methods were applied for cleaning the surface (gold-coated glass)—(1) standard cleaning procedure (SCP) using acetone, isopropyl alcohol, and deionized water and (2) SCP followed by air plasma cleaning. This work discusses the effect of the cleaning procedures on surface roughness, contact angle, and surface chemistry using atomic force microscopy, optical microscopy, and an X-ray photoelectron spectroscope meter. The results showed that SCP before the SPRi is a proper surface-treatment method. The effect of adsorbed VOCs during dropwise condensation on a surface treated with SCP was measured to be 0.0025 (reflectivity unit), which was 70% smaller than the reflectance associated with a monolayer water film. The results of this work confirm a monolayer water film observation during the dropwise condensation, which has been reported before.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Assessment and Non-Destructive Evaluation of the Influence of Residual Solvent on a Two-Part Epoxy-Based Adhesive Using Ultrasonics

Polymers are increasingly being used in higher demanding applications due to their ability to tailor the properties of structures while allowing for a weight and cost reduction. Solvents play an important role in the manufacture of polymeric structures since they allow for a reduction in the polymer’s viscosity or assist with the dispersion of fillers into the polymer matrix. However, the incorrect removal of the solvent affects both the physical and chemical properties of polymeric materials. The presence of residual solvent can also negatively affect the curing kinetics and the final quality of polymers. Destructive testing is mainly performed to characterize the properties of these materials. However, this type of testing involves using lab-type equipment that cannot be taken in-field to perform in situ testing and requires a specific sample preparation. Here, a method is presented to non-destructively evaluate the curing process and final viscoelastic properties of polymeric materials using ultrasonics. In this study, changes in longitudinal sound speed were detected during the curing of an aerospace epoxy adhesive as a result of variations in polymer chemistry. To simulate the presence of residual solvent, samples containing different weight percentages of isopropyl alcohol were manufactured and tested using ultrasonics. Thermogravimetric analysis was used to show changes in the decomposition of the adhesive due to the presence of IPA within the polymer structure. Adding 2, 4, and 6 wt.% of IPA decreased the adhesive’s lap shear strength by 40, 58, and 71%, respectively. Ultrasonics were used to show how the solvent influenced the curing process and the final sound speed of the adhesive. Young’s modulus and Poisson’s ratio were determined using both the longitudinal and shear sound speeds of the adhesive. Using ultrasonics has the potential to non-invasively characterize the quality of polymers in both an in-field and manufacturing settings, ensuring their reliability during use in demanding applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1977

Effect of transient liquid flow on retention characteristics of screen acquisition systems

A design analysis, is developed based on experimental data, to predict the effects of transient flow and pressure surges (caused either by valve or pump operation, or by boiling of liquids in warm lines) on the retention performance of screen acquisition systems. A survey of screen liquid acquisition system applications was performed to determine appropriate system environment and classification. A screen model was developed which assumed that the screen device was a uniformly distributed composite orthotropic structure, and which accounted for liquid inflow/outflow, gas ingestion quality, screen stress, and liquid spill. A series of 177 tests using 13 specimens (5 screen meshes, 4 screen device construction/backup methods, and 2 orientations) with three test fluids (isopropyl alcohol, Freon 114, and LH2) provided data which verified important features of the screen model and resulted in a design tool which could accurately predict the transient startup performance acquisition devices.

Cady, E. C.↗
NASA NTRS1981

"Densified" tiles form stronger bonds

Application of colloidal silica more than doubles bond strength of ceramic tile/substrate attachments. "Densification" process strengthens surface where tile attaches to felt strain-isolator pad, redistributing stresses and preventing failures at that point. First, isopropyl alcohol is applied to bottom tile surface. Second, aqueous mixture of cementing colloidal silica and reinforcing ball-milled silica particles is painted on tile. Finally, after drying, tile is rewaterproofed by exposure to vapors or methyltrimethoxysilane and acetic acid.

Dotts, R. L.↗
NASA NTRS1984

Removing Images From Microfilm

Film softened, scraped, and then dried. Unwanted images removed from microfilm for softening base film with hot water, scraping film and drying with isopropyl alcohol. Method simple and no visible damage to film.

Taylor, L. L.↗