Alumina deactivated

Ethoxymethyl)phthalonitriie (12 2,88 g, 15.5 mmol), Fe(OAc)2 (672 mg, 3.9 mmol), and two drops of DBU were heated in anhyd hexan-l-ol (120 mL) at 150rC until all the phthalonitrile had reacted (TLC). The mixture was cooled and the solvent was removed under reduced pressure. The residue was washed with McOH and purified by column chromatography [neutral alumina (deactivated with 4% H,0), CHC1, ... 

Alumina-deactivated GC of FFAs Milk, milk fat, Butter, cheese, milk powder Deeth et al. (1983)... 

The saturate and aromatic hydrocarbons were separated from the alcohols by elution chromatography on alumina deactivated with 3.8% water in a ratio of 5 g of alumina to 1 g of oil, by successive elutions with (1) 30 mL of cyclohexane and (2) 50 mL of 2% benzene in cyclohexane. The alcohols were recovered for future analysis by washing the column with 100 mL of ethyl ether. The solvent was removed from the hydrocarbon fraction and the yield of saturates plus aromatics calculated back to the neutral oil. The percentage of olefins was determined by difference. The percentage of aromatic material was determined as the difference between the saturates and aromatics from the hydroboration and the saturates from acid absorption. 

The presence of the copper-chromite phase resulted in less deactivation as compared to copper on alumina. Deactivation of copper on alumina was attributed to the slow formation of well dispersed but less active copper oxide, probably in the form of a surface CuAl20 > spinel, as well as to the formation of Cu°-aggregates. 

The oxidations are all rapid, and the decrease in yield is due to decreasing rate of addition in the order (2)>(5)>(7). In experiments on a 10-mmole scale the reaction mixture was treated with 7 g. of Woelm neutral alumina and the whole cvapoi utcd to dryness at reduced pressure. T he resulting solid was packed on top of a chromatographic column of. 5(1 g. of Woelm alumina deactivated by 10% of water, and the chromatogram was then develuped (( ( U C H CTy). 

The reaction products were separated and identified by Gas Chromatography (GC) on a 50 m PLOT capillary column coated with alumina deactivated by KCl. 

BaA and BaP is added and the entire sample is extracted with methylene chloride (250-, 100-, and 100-mL portions). The extracts are combined, 10 mL of isooctane added, and the solution evaporated to about 10 mL. When the solution approaches 10 mL, a second 10-mL volume of isooctane is added. This is repeated three times. The isooctane solution is made up to 75 mL and extracted with three 100-mL portions of dimethyl sulfoxide (DMSO) that contains 20% phosphoric acid. The DMSO extracts are each washed with three 30-mL portions of fresh isooctane, combined and diluted with 500 mL of water. This solution is extracted with three 80-mL portions of isooctane. The isooctane extracts are combined, rinsed once with water, and evaporated to 25 mL. At this point, a 1-mL portion of the solution is removed for intermediate radioassay and a UV scan. Usually the concentrate is sufficiently free from interferences and is evaporated down to about 0.05 mL and an aliquot injected into the GC. If further purification is indicated, the solution is chromatographed on a 1.1-cm X 90-cm column containing 75 g of Woelm Neutral Alumina deactivated with 2% water. Before deactivation, the alumina is dried in an oven for 1 hr at 150°C. The solvent elution schedule is as follows 25 mL cyclohexane prewash, 25-mL sample in cyclohexane, 100 mL cyclohexane, 100 mL cyclohexane-methylene chloride (9 1), 100 mL cyclohexane-methylene chloride (1 1), 100 mL methylene chloride. After the first 125 mL has eluted, 10 cuts are then radioassayed and combined into a single PNA fraction. This fraction is evaporated to about 0.05 mL in preparation for the GC-UV finishing step. Figure 2 is a diagram of the wastewater procedure. 

Alumina-KCl Alumina deactivated with KCl least polar alumina Cl—C8 hydrocarbon isomers lowest retention of olehns relative to comparable paraffin. Quantitation of dienes, especially propadiene and butadiene in presence of ethylene and propylene. 

Alumina-S Alumina deactivated with sodium sulfate midrange polarity of alumina phases general-purpose alumina excellent for resolving acetylene from butane and propylene from isobutane. 

Amorphous Silica—Alumina Based Processes. Amorphous siHca—alumina catalysts had been used for many years for xylene isomerization. Examples ate the Chevron (130), Mamzen (131), and ICI (132—135). The primary advantage of these processes was their simpHcity. No hydrogen was requited and the only side reaction of significance was disproportionation. However, in the absence of H2, catalyst deactivation via coking... 

Many forms of chromatography have been used to separate mixtures of quinoline and isoquinoline homologues. For example, alumina saturated with cobalt chloride, reversed-phase Hquid chromatography, and capillary gas chromatography (gc) with deactivated glass columns have all been employed (38,39). 

An unstabilized high surface area alumina siaters severely upon exposure to temperatures over 900°C. Sintering is a process by which the small internal pores ia the particles coalesce and lose large fractions of the total surface area. This process is to be avoided because it occludes some of the precious metal catalyst sites. The network of small pores and passages for gas transfer collapses and restricts free gas exchange iato and out of the activated catalyst layer resulting ia thermal deactivation of the catalyst. 

Catalyst Deactivation. Catalyst deactivation (45) by halogen degradation is a very difficult problem particularly for platinum (PGM) catalysts, which make up about 75% of the catalysts used for VOC destmction (10). The problem may weU He with the catalyst carrier or washcoat. Alumina, for example, a common washcoat, can react with a chlorinated hydrocarbon in a gas stream to form aluminum chloride which can then interact with the metal. Fluid-bed reactors have been used to offset catalyst deactivation but these are large and cosdy (45). 

Purified by chromatography on a column of deactivated alumina or magnesium oxide, or on a thin layer of silica gel G (Merck), using dichloromcthane/dicthyl ether (9 1) to develop the chromatogram. Stored in the dark and in an inert atmosphere at -20 . 

Purified by chromatography on partially deactivated alumina or magnesia, or by using a thin layer of silica gel G with 4 1 cyclohexane/diethyl ether as the developing solvent. Stored in the dark at -20°. 

Lycoxanthin ( F, F-carotene-16-ol) [I989I-74-8J M 268.3, m 173-174°, Eicm 3360 (472.5nm), also X ax 444 and 503nm in pet ether. Crystd from diethyl ether/light petroleum, benzene/pet ether or CS2- Purified by chromatography on columns of CaC03, Ca(OH)2 or deactivated alumina, washing with benzene and eluting with 3 1 benzene/MeOH. Stored in the dark, in an inert atmosphere, at -20°. 

Physalien (all trans /J-carotene-3,3 -diol dipalmitate) [144-67-2] M 1044, m 98.5-99.5°, A (Xmax) 1410 (449nm), 1255 (478nm) in hexane. Purified by chromatography on water-deactivated alumina, using hexane/diethyl ether (19 1) to develop the column. Crystd from benzene/EtOH. Stored in the dark, in inert atmosphere, at 0°. 

Phytofluene [540-05-6] M 549.0, b 140-185°(bath temp)/0.0001m A (Xmax) 1350 (348nm) in pet ether, X ax 331, 348, 267. Purified by chromatography on partially deactivated alumina [Kushwaha et al. J Biol Chem 245 4708 1970]. Stored as a soln in pet ether under nitrogen at -20°. 

Separated from retinol by column chromatography on water-deactivated alumina with hexane containing a very small percentage of acetone. Also chromatographed on TLC silica gel G, using pet ether/isopropyl ether/acetic acid/water (180 20 2 5) or pet ether/acetonitrile/acetic acid/water (190 10 1 15) to develop the chromatogram. Then recrystd from propylene at low temperature. 

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