Hot filtration test

Fig. 2.1.6.4 Hot filtration test and catalyst recycling for hydrogenation of dimethyl itaconate over RhDuphos/ AI-SBA-15.

In order to prove that the reaction was catalyzed heterogeneously and to exclude the possibility of leaching and homogeneous catalysis, hot filtration tests were performed [44]. For the dimethyl itaconate hydrogenation, removal of the COD-RhDuphos immobilized on Al-SBA-15 effectively stopped the reaction after 5 h. After 24 h, the conversion of the filtered sample remained at 40%, whereas the original batch with catalyst was converted completely (Fig. 2.1.6.4). 

Hot filtration test a test for the stability of a petroleum product. 

Flocculation Point. Figure 4 shows that the flocculation point of a reactor effluent sample (cracked atmospheric bottom) is much lower than that of the reactor feed. Generally, the flocculation point decreases as the amount of solids in the sample increases. This has been confirmed by the Shell Hot Filtration Test IP/375/ASTM 4870 procedure. 

With microwave-assisted technology, Porcheddu and colleagues [11] prepared benzimidazoles via one-pot C-H activation of tertiary amines/oxidative cycliza-tion with 1,2-phenylenediamine in the presence of Pd/C (Scheme 14.10). To ascertain the heterogeneous character of the catalytically active species in this process, further leaching studies were performed. Both Sheldons hot filtration test and atomic absorption spectroscopy analysis (ICP-MS) of the filtrate detected no significant quantities of leached Pd in solution, suggesting that the reaction was a heterogeneous process. 

The combination of several of the above described approaches can be also used. Thus, precious metal catalysts can be supported on nanomaterials and combined with ILs. The supported gold NPs on graphene oxide (GO) with an ionic liquid framework (Au GO-IL) has been shown to be a highly active, and leaching tests, such as hot filtration test and AAS analysis, indicate that the catalytic reaction is mainly heterogeneous in nature. The reusability of this catalyst was tested for 5 x without a significant decrease in its catalytic... 

Hot filtration test. It gives the total amount of sediment in the oil, but does not give information about the stability of an oil. 

Maitlis filtration test. To investigate whether the Pd-doped perovskite is the actual catalyst, or a reservoir of soluble Pd, a Maitlis filtration test (10) was performed. The reaction of 4-bromoanisole with 4-phenylboronic acid, catalyzed by BaCeo 95Pdo os02 95, was intemipted at 20 s and 1 min, corresponding to conversions of 16 and 45%, respectively, by filtering the hot reaction mixture to remove the solid perovskite. The filtrates were allowed to cool to room temperature without stirring. After 3 h, the biatyl yields in both samples were estimated to be 100% by H NMR. 

Copper Sulphate Pentahydrate. Calculate what amount of copper sulphate crystallohydrate (blue vitriol) has to be taken for 10 ml of water to prepare a solution saturated at60°C (see Appendix 1, Table 1). Bring the solution obtained at the indicated temperature almost up to boiling and rapidly filter it through a fluted filter on a funnel for hot filtration (the funnel must be hot). Close the test tube with the filtrate with a piece of cotton wool. If crystals have formed in the filtrate, dissolve them by careful heating. Cool the solution and introduce a minute crystal of the initial salt into it. What is observed Does the temperature of the solution change ... 

Measurement of the Viscosity.—This can be carried out either on the solution prepared in the cold or on that prepared in the hot. In the former case, 100 grams of the dextrin are shaken with 500 c.c. of distilled water at 17-5° until the whole of the soluble part has dissolved, the liquid being filtered through a dry filter and the filtrate tested in the Engler viscometer (see Vo I, p. 352). In the second case, the solution is prepared in the hot and the viscosity measured when cold. The value obtained is compared with that given by a standard dextrin under the same conditions. 

It is convenient to test the residue R for oxalate here. Dissolve it by pouring hot dilute sulphuric acid into the filter. Treat the hot filtrate with a few drops of 0 004m potassium permanganate solution. If the permanganate solution is reduced, oxalate is present. If no reduction occurs, the presence of fluoride is indicated. 

The oxime is freely soluble in water and in most organic liquids. Recrystallise the crude dry product from a minimum of 60-80 petrol or (less suitably) cyclohexane for this purpose first determine approximately, by means of a small-scale test-tube experiment, the minimum proportion of the hot solvent required to dissolve the oxime from about 0-5 g. of the crude material. Then place the bulk of the crude product in a small (100 ml.) round-bottomed or conical flask fitted with a reflux water-condenser, add the required amount of the solvent and boil the mixture on a water-bath. Then turn out the gas, and quickly filter the hot mixture through a fluted filter-paper into a conical flask the sodium chloride remains on the filter, whilst the filtrate on cooling in ice-water deposits the acetoxime as colourless crystals. These, when filtered anddried (either by pressing between drying-paper or by placing in an atmospheric desiccator) have m.p. 60 . Acetoxime sublimes rather readily when exposed to the air, and rapidly when warmed or when placed in a vacuum. Hence the necessity for an atmospheric desiccator for drying purposes. 

Hydrolysis of benzanilide. Place 5 g. of benzanilide and 50 ml. of 70 per cent, sulphuric acid in a small flask fitted with a reflux condenser, and boU gently for 30 minutes. Some of the benzoio acid will vapourise in the steam and solidify in the condenser. Pour 60 ml. of hot water down the condenser this will dislodge and partially dissolve the benzoic acid. Cool the flask in ice water filter off the benzoic acid (anifine sulphate does not separate at this dilution), wash well with water, drain, dry upon filter paper, and identify by m.p. (121°) and other tests. Render the filtrate alkaline by cautiously adding 10 per cent, sodium hydroxide solution, cool and isolate the aniline by ether extraction. Recover the ether and test the residue for anifine (Section IV,100). 

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