Isopropyl alcohol, IPA

Example Separation of 2-Propanol—Water. Consider the separation of a binary mixture of 60 mol % water and 40 mol % 2-propanol (or isopropyl alcohol (IPA)) into two products consisting of 2-propanol of 99.5 mol % purity and water with <100 ppm 2-propanol impurity. 

Fig. 4. Distillation of aqueous isopropyl alcohol (IPA), where A is the a2eotrope, combined with (a) pervaporation and (b) adsorption.

Isopropyl alcohol (IPA) or benzyl alcohol (toluol) often are used in the formulation (as early components in the order of addition) to dissolve the surfactant-detergent base [e.g., Duomeen OL (Akzo Nobel Chemicals, Inc.) or Triton N101 (Union Carbide Corp.)]. 

Using the Wilson equation, calculate the activity coefficients for isopropyl alcohol (IPA) and water in a mixture of IPA, methanol, water, and ethanol composition, all mol fraction ... 

Figure 12.33 Separation of isopropyl alcohol (IPA) and water mixture using di-isopropyl ether (DIPE) as entrainer in heterogeneous azeotropic distillation.

All standard cleaning processes for silicon wafers are performed in water-based solutions, with the exception of acetone or (isopropyl alcohol, IPA) treatments, which are mainly used to remove resist or other organic contaminants. The most common cleaning procedure for silicon wafers in electronic device manufacturing is the deionized (DI) water rinse. This and other common cleaning solutions for silicon, such as the SCI, the SC2 [Kel], the SPM [Ko7] and the HF dip do remove silicon from the wafer surface, but at very low rates. The etch rate of a cleaning solution is usually well below 1 nm min-1. 

If the ITO-coated side of the electrode does not have a purple sheen, then the electrode is either dirty or damaged. The best way to clean an ITO electrode is with a low-molecular-weight alcohol such as isopropyl alcohol (IPA), which does not adsorb to the oxide layers. Some modem laboratories have advanced facilities for burning off the surface contaminants by using a low-pressure plasma. Few analysts would employ ITO-coated electrodes if they always required such stringent conditions prior to routine analyses. 

Catalysts described in the literature and in patents contain Pd(OAc)2 and PR3 (R = alkyl and aryl). Short-chained alcohols (Ci to C4) are typically used as nucleophiles (Scheme 3) and at reaction conditions of 120 °C, 50 bar CO and 15 hours, the desired linear (isopropyl-)nonadienoate is formed as the main product with isopropyl alcohol (IPA) as the alcohol component. 

There are many other commercial alcohols besides methanol. This chapter treats the ones traded in the largest volumes ethyl alcohol, isopropyl alcohol (IPA), normal butyl alcohol (NBA), 2-ethyl hexanol (2-EH) and li4-butanediol (BDO). 

Membranes cast from THF-formamide, dried for 200 seconds in room temperature air, and gelled for one hour, were tested for desalination performance. The results are listed in Table VIII. The best results were obtained with membranes cast from AO 60 and 70 30 THF-formamide and gelled in isopropyl alcohol (IPA)-see discussion below concerning gelation media. Of these two systems the AO 60 is superior. This... 

Table 10. Dependence of the molecular-mass distribution of the oligomers on the polymerization conditions of phenylglycidyl ether (PhGE) under the action of dimethylbenzylamine (DMBA) and isopropyl alcohol (IPA) 152 1S8>...

A systematic study has been developed by Christopoulou and Perkins (78). They employed three different types of detectors (differential refractometer, variable wavelength detector set at 205 or 232 nm, and infrared detector at 5.72 /zm) and three commercially packed columns (I, LC-Si, 250 X 4.6-mm ID, 5-/zm particle size II, LC-18, 250 X 4.6-mm ID, 5-/zm particle size III, LC-18, 150 X 4.6-mm ID, 5-/zm particle size). The various mobile phases used were system I, 1.5% isopropyl alcohol (IPA) in hexane system II, acetonitrile/acetone (1 1) system III, acetonitrile (spectra) system IV, acetonitrile/methylene chloride (3 1). Columns I and II were used with solvent systems I and II, respectively, and refractometry was the mode of detection. Column III was used with solvent system III and UV detection at 205 or 232 nm, as well as with solvent system IV and infrared detection at 5.72 /zm. 

Guanidine + 15% coco diamine. Dose at 20 to 100 ppm. Effective as a broad-spectrum slimicide, but isopropyl alcohol (IPA) required as part of the formulation, which adds to the oxidizable demand of the system. 

The same factors also apply to sanitizing agents used to wipe down cleaned equipment. For example, it is a quite common practice to wipe down equipment used to manufacture nonsterile pharmaceuticals with isopropyl alcohol (IPA) subsequent to cleaning the equipment. This final IPA wipedown can be a source of contamination if the IPA is not subsequently removed. Although IPA is fairly volatile, it can pool in the intricate surfaces of a closed... 

The SiC-coated or uncoated MWCNTs are dispersed in isopropyl alcohol (IPA) using ultrasonic vibration for 5 min. They are then mixed with nanometersized SiC (mean diameter 30 nm) and B4C (mean diameter 240 nm) powders in IPA using ultrasonic vibration for 10 min. The B4C is added at 2 wt% as a sintering aid. After the mixing, the IPA solution is evaporated and the mixed powders are dried at 100°C. The MWCNTs are uniformly dispersed without aggregation. The mixed powders are sintered at 1800°C at 40 MPa for 5 min under a vacuum by means of PECS. The content of the SiC-coated MWCNTs is varied between 1 and 5 vol%. 

Isopropyl alcohol (IPA) is sometimes added to KOH in order to reduce the etchant surface tension. This in turn assists in releasing H2 bubbles and in dissolving organic contaminants. So the addition of IPA avoids the micromask effect and produces smoothly etched channels [303]. 

Isopropyl alcohol (IPA) has been called the first petrochemical. Both historically and today, it is... 

A major project added to the information about isopropyl alcohol (IPA) from earlier trials, 97,98 and showed it can be as effective an extraction solvent as hexane.99 However, because of high retrofitting costs, IPA is not likely to be implemented while hexane-type hydrocarbons are allowed. 

All ductwork sections should be cleaned and sealed with plastic wrap at the time of fabrication until just prior to installation or start-up to prevent contaminants from accumulating inside air-handling passageways. The sections of ductwork should be unsealed only as required for installation. Open ends of ducts and fans should remain sealed until connecting duct is about to be installed. A final isopropyl alcohol (IPA) wipe-down of all interior duct sections and fan surfaces should be done immediately prior to installation. 

Samples were exposed to synchrotron radiation through a gold-on-boron nitride mask and then developed using various mixtures of isopropyl alcohol (IPA) and methyl isobutyl ketone (NIBK). Development was conducted under stirred conditions using a constant temperature bath at 23°C and was terminated by blow drying with Freon gas. Film thicknesses were measured using a Tencor Alpha Step. 

Leenars has shown both from theoretical considerations and experimental measurements that the passage of a liquid-gas phase boundary along the substrate may result in particle removal. It is shown that since both Ep/g (Equation (9.2)) and (Equation (9.5)) are both proportional to R, the surface tension effects can be utilized to clean particles of all sizes. Theoretical considerations are described in Reference (11). By adopting a suitable combination of the cleaning liquid, particle, and surface properties, adhesion forces can be overcome by surface-tension-related forces — the adhesion of the particles to the liquid-gas phase boundary is stronger than their adherence to the substrate. This leads to subsequent removal of the particle into the moving liquid. McConnell has shown that isopropyl alcohol (IPA) can be used to achieve this type of... 

In recent tests (29), polyimide membranes showed higher rejection rates with hexane and isopropyl alcohol (IPA) than that of the polyamide membrane. The permeate flux of polyamide membrane with the crude cottonseed oil-hexane and IPA miscellas (20% by weight) were 2.25-5 times of the polyimide membrane (Table 13). The highest fluxes obtained with hexane and IPA misceUas were 6.6 1/m.hr and 1.4 1/m.h, respectively. 

The most important consideration in the selection of the filter is the compatibility of the hlter materials of constmction with the solvent. The solvents used in pharmaceutical processes can be very aggressive. They include acetone, methanol, ethanol, isopropyl alcohol (IPA), acetonitrile, dimethyl acetamide, dimethyl formamide (DMF), ethyl acetate, tetrahydrofuran (THF), methyl isobutyl ketone (MIBK), and methyl ethyl ketone (MEK). Filters with PTFE membranes and polypropylene supports are used in most applications. 

Solubility determinations were used to characterize the polymorphism of 3-(((3-(2-(7-chloro-2-quinolinyl)-( )-ethenyl)-phenyl)-((3-dimethylamino-3-oxopropyl)-thio)-methyl)-thio)-propanoic acid. " The solubility of Form II was found to be higher than that of Form I in both isopropyl alcohol (IPA, solubility ratio equal to 1.7 over the range of 5-55°C) and methyl ethyl ketone (MEK, solubility ratio equal to 1.9 over the range of 5-55°C), indicating that Form I is the thermodynamically... 

The model developed has been used to study the effect of catalyst pretreatment and operation temperatures upon the activation/deactivation processes during isopropyl alcohol (IPA) dehydrogenation on a Cu/Si02 catalyst. 

A similar etch rate dependence on concentration is found for the three major surfaces in KOH-IPA solutions as shown in Fig. 7.14, but unlike at lower temperatures, solution stirring has little effect on the etch rate. ° The activation energy of the etching process is 0.56-62 eV for KOH of different concentrations indicating that the etching is controlled by a surface process. KOH solutions are often buffered with isopropyl alcohol (IPA), which results in a decrease of etch rates. ... 

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