Decanting fluid

Method 1. From ammonium chloroplatinate. Place 3 0 g. of ammonium chloroplatinate and 30 g. of A.R. sodium nitrate (1) in Pyrex beaker or porcelain casserole and heat gently at first until the rapid evolution of gas slackens, and then more strongly until a temperature of about 300° is reached. This operation occupies about 15 minutes, and there is no spattering. Maintain the fluid mass at 500-530° for 30 minutes, and allow the mixture to cool. Treat the sohd mass with 50 ml. of water. The brown precipitate of platinum oxide (PtOj.HjO) settles to the bottom. Wash it once or twice by decantation, filter througha hardened filter paper on a Gooch crucible, and wash on the filter until practically free from nitrates. Stop the washing process immediately the precipitate tends to become colloidal (2) traces of sodium nitrate do not affect the efficiency of the catalyst. Dry the oxide in a desiccator, and weigh out portions of the dried material as required. 

Steps. Thermal-swing cycles have at least two steps, adsorption and heating. A cooling step is also normally used after the heating step. A portion of the feed or product stream can be utilized for heating, or an independent fluid can be used. Easily condensable contaminants may be regenerated with noncondensable gases and recovered by condensation. Water-iminiscible solvents are stripped with steam, which may be condensed and separated from the solvent by decantation. Fuel and/or air may be used when the impurities are to be burned or incinerated. 

Power for each Hquid and the soHd phase must be added to get Pp. P, the soHds process power, = T -AN for scroU decanters, where = conveyor torque and AN = differential speed between bowl and conveyor. Pp is the friction power, ie, loss in bearings, seals, gears, belts, and fluid couplings. P, the windage power, = K and fi = viscosity of surrounding gas p = density of gas D = rotor outside diameter N = rpm and K = shape... 

Factor for establishing ty pe of flow for decanters, Reference [321, U = Viscosity of surrounding fluid, cp, except where it is lb/(ft-sec)... 

A liquid-liquid mixture containing 6 kg s-1 of water with 0.5 kg s-1 of entrained oil is to be separated in a decanter. The properties of the fluids are given in Table 8.4 below. 

Samples were collected in 4-kg amber glass jars fitted with Teflon-lined caps and were frozen at —20 °C until processing. At the time of workup, the samples were thawed and allowed to settle overnight at 4 °C, and the supernatant fluids, about 75 of the volume of the parent samples, were decanted. For each sample, the remaining slurry was centrifuged for 20 min at 8000 X g at 6 °C. This supernatant fluid was decanted and combined with the previous supernatant fluid and then stored for processing as an aqueous sample (14, 15). The... 

When the evaporation lias been carried sufficiently far, three or four ounces of water should he added after which the contents of the flask must be allowod to remain in perfect rest until the undissolved matter has Completely subsided, and the supernatant fluid fa quite dear. The latter is then to he carefully decanted or filtered off, and to the residue about an ounce of fresh water must be added, left to stand till clear, again decanted or filtered and this operation repeated five or bix times, always adding the later washings to the first portion of fluid. The solution of gold now obtained will be very dilute. Add to it, therefore, a few drops of hydrochloric acid, and then introduce the protosulphate of iron, which, when the liquid is well stirred, will speedily precipitate the whole of the gold in the form of a brown powder. If oxalic acid be used for the same purpose, the liquid onght to be boiled. When the whole of tire precipitate appears to have settled to the bottom, a few drops of the clear supernatant liquid should be taken out on the end of a rod, placed upon a surface of clean whits porcelain, and... 

Selenium Sulphoxide or Sulphur - Selenium Sesquioxide, SeS03.—This has already been mentioned in connection with the solubility of selenium in sulphuric acid (pp. 291, 300) as the probable cause of the green colour produced. It is also obtainable, similarly to sulphur sesquioxide, from fluid sulphur trioxide by the addition of powdered amorphous selenium, the sulphoxide being insoluble in the sulphur trioxide, so that the latter can be decanted off ... 

An alternative carrier-gas system uses a condensable gas, such as steam, as the carrier sweep fluid. One variant of this system is illustrated in Figure 9.7(d). Low-grade steam is often available at low cost, and, if the permeate is immiscible with the condensed carrier, water, it can be recovered by decantation. The condensed water will contain some dissolved organic and can be recycled to the evaporator and then to the permeate side of the module. This operating mode is limited to water-immiscible permeates and to feed streams for which contamination of the feed liquid by water vapor permeating from the sweep gas is not a problem. This idea has been discovered, rediscovered, and patented a number of times, but never used commercially [37,38], If the permeate is soluble in the condensable... 

Al203, are dissolved in 2,300 ml of water, to which a solution comprising 272 g of caustic soda with 800 ml of water, is slowly added with stirring. Thereafter, a solution comprising 414 g of sodium silicate (Na20, 9%, Si02, 29%) with 100 ml of water is added, the mixture is heated and is stirred for five hours, while keeping the temperature at 60°C. When the reaction mixture becomes neutral it is allowed to cool and to stand, the supernatant fluid is withdrawn and the white gel-like precipitate is washed by decantation to remove the impurities and dried at 105°-110°C and 350 g of white powder of fine particle size is obtained as the final product (almasilate). 

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