Acid temperature control calculation

The terms in Eq. (6) include the gravitational constant, g, the tube radius, R, the fluid viscosity, p, the solute concentration in the donor phase, C0, and the penetration depth, The density difference between the solution and solvent (ps - p0) is critical to the calculation of a. Thus, this method is dependent upon accurate measurement of density values and close temperature control, particularly when C0 represents a dilute solution. This method has been shown to be sensitive to different diffusion coefficients for various ionic species of citrate and phosphate [5], The variability of this method in terms of the coefficient of variation ranged from 19% for glycine to 2.9% for ortho-aminobenzoic acid. 

As a result of the experimental studies, the simulations, and the calculations, the following safety precautions were taken. The only foreseeable process upset resulting in a temperature excursion in the nitrators is a deviation in the feed ratios. Control features and interlocks were installed to reduce this possibility. The sulfuric acid flow control station was designed in such a way that flow of this process heat sink is not halted upon complete failure of the flow controller. Low sulfuric acid flow results in automatic shutdown of the nitric acid and benzene feeds. 

Kinetic Studies. Peracetic Ac id Decomposition. Studies with manganese catalyst were conducted by the capacity-flow method described by Caldin (9). The reactor consisted of a glass tube (5 inches long X 2 inches o.d.), a small centrifugal pump (for stirring by circulation), and a coil for temperature control (usually 1°C.) total liquid volume was 550 ml. Standardized peracetic acid solutions in acetic acid (0.1-0.4M) and catalyst solutions also in acetic acid were metered into the reactor with separate positive displacement pumps. Samples were quenched with aqueous potassium iodide. The liberated iodine was titrated with thiosulfate. Peracetic acid decomposition rates were calculated from the feed rate and the difference between peracetic acid concentration in the feed and exit streams. 

A stream of hydrofluoric acid (1) in water (2) at 120°C and 200 kPa contains 12% mole hydrofluoric acid (HF). It is proposed to concentrate the HF in solution by partial vaporization in a single stage, by means of temperature and pressure control. Calculate the resulting liquid composition and the fraction vaporized at 120°C and 135 kPa. Can this process be used to concentrate the liquid for any starting composition Use the van Laar equation for liquid activity coefficients and assume ideal gas behavior in the vapor phase. The vapor pressures of HF and water at 120°C are 1693 and 207 kPa, respectively, and the van Laar constants are Ajj = -6.0983, A2] = -6.9658 (see Problems 1.8 and 1.9). 

The derign of a continuous esterification column, at one time accomplished by empirical methods, can be carried out by Calculation, provided that sufficient data are available. Commonly, the apparatus used is a bubble-cap column. In the case ot high-boiling esters, such as the phtha-lates, the water produced in the reaction is removed overhead and the product is withdrawn from the bottom plate. A mixture of the alcohol, acid, and acid catalyst is fed to the top plate of the column, and the esterification is carried out as the mixture flows through the column. The probr lem of calculating the number of plates necessary is complicated by the laws of hiass action, kinetics, and distillation, which all operate simultaneously. The variables, mole ratio of reactants, catalyst concentration, and temperature, control the kinetics of the reaction. The distillation laws must take into account the fact that moles of reactants are replaced by moles of products on each plate. 

Early estimates of the first association constant were made in the 1930 s by Bray and Hershey (F2) and MoUer (F8) using potentiometric measurements. In 1942, Rabinowitch and Stockmayer (F9) presented the results of their spectroscopic study under controlled acidity, temperature and ionic strengths. From their results they calculated estimates of the first three association constants ... 

The amounts oi adsorption of the polymer on latex and silica particles were measured as follows. Three milliliters of the polymer solution containing a known concentration was introduced into an adsorption tube(lO ml volume) which contained 2 ml of latex (C = l+.O wt %) and silica(C = 2.0 wt %) suspensions. After being rotated(l0 rpm) end-over-end for 1 hr in a water bath at a constant temperature, the colloid particles were separated from the solution by centrifugation(25000 G, 30 min.) under a controlled temperature. The polymer concentration that remained in the supernatant was measured colorimetrically, using sulfuric acid and phenol for the cellulose derivatives(12), and potassium iodide, iodine and boric acid for PVA(13). From these measurements, the number of milligrams of adsorbed polymer per square meter of the adsorbent surface was calculated using a calibration curve. 

To a distillation flask is added 29.0 gm (0.244 mole) of 3-bromopropyne and 2.5 gm (0.0174 mole) of dry cuprous bromide. The flask is attached to a concentric-tube column (25-30 theoretical plates), and the temperature of the flask is controlled so that the takeoff temperature at the head remains at 72.8°-73.5°C. In 24 hr, 24.4 gm (84 %) of bromopropadiene of 75-85 % purity is obtained. The remaining 3-bromopropyne (propargyl bromide) is removed by washing the product with a 40 % aqueous solution of diethylamine. Three to four moles of diethylamine is used for each mole of propargyl bromide in the product as calculated from VPC or refractive index data. After swirling the mixture (acidified with 15 % hydrochloric acid) for hr, the organic layer is separated, washed with water, dried over potassium carbonate, and distilled quickly under reduced pressure into a Dry Ice-cooled receiver to afford pure bromopropadiene, b.p. 72.8°C (9760 mm), w ° 1.5212, 1.5508. 

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