Liquid filtration bulk water filters

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. 

To 26 gms. (2 mols.) of benzoyl chloride are added gradually 10 gms. of o-toluidine (1 mol.) and the mixture is heated for 15 hours in an oil bath at 230°. A brown viscid liquid is formed which solidifies on cooling. In order easily to separate the 4-amino-3-methylbenzophenone, the mass is hydrolysed by boiling for 14 hours with excess of alcohol containing half its bulk of cone, hydrochloric acid. The product thus obtained is steam distilled when alcohol and then ethyl benzoate pass over. The acid residue which contains the hydrochloride of the base is boiled for some time with water and filtered from tarry matter. The filtrate is then made slightly alkaline, and o-toluidine derived from untransformed dibenzoyl-... 

Test for Nitrobenzene.—About 25 grams of the substance are digested for some hours with 30 c.c. of cold alcohol, the mass being then filtered, and the filtrate diluted with an equal volume of water and heated on a water-bath with a little zinc dust and about 3 grams of caustic potash until the bulk of the alcohol is expelled. The residual aqueous liquid is decanted off and extracted with an equal volume of ether, the ethereal layer being separated and evaporated and the residue dissolved in 3 c.c. of water. This solution is heated with a few drops of chloroform and alcoholic potassium hydroxide solution in presence of aniline, derived from nitrobenzene in the marzipan, the characteristic odour of phenyl-carbylamine is emitted. 

The feedstock was mixed with 3% (w/w) sulfuric acid solution in 500-mL closed universal flasks with a liquid-to-solid ratio of 8 (w/w). The moisture content of the samples was included as water in the material balances. The mixtures were allowed to stand for 10 min at room temperature in order to equilibrate the acid concentrations between the bulk phase and biomass. Hydrolysis was performed in an autoclave at 130°C for pre-established isothermal periods ranging from 2 to 240 min. The flasks were placed inside the autoclave at 100°C, and the heating time to reach 130°C was recorded. After the reaction time had elapsed, the autoclave was rapidly cooled down and the hydrolysate and solid phase were recovered by filtration (Whatman no. 1 filter paper). All experiments were done at least in duplicate. 

Particulate matter, obtained from the filtration process, can be analyzed with the same analytical methods normally used for sediment samples. Solvents used in the filter extraction are generally the same as those previously described for liquid-liquid extraction (i.e., -hexane [152], toluene [31], and pentane/mefhylene chloride (2 1) [85]). However, water-miscible solvents can also be used such as acetone, ethyl acetate and methanol (n-heptane/acetone (1 1) [67], hexane/acetone (3 2) [10], dichloromethane/methanol (2 1) [46], and dichloromethane/methanol (2 1) [135]). The extraction process is carried out in a Soxhlet extractor or, more simply, in an ultrasonic bath— this improves the exchange process between the particle surface and the bulk of the organic solution. Pressurized liquid extractions (accelerate solvent extraction) can be used for a more efficient extraction, above all in terms of extraction times [10,67]. 

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