B determination

In a particular analysis the selectivity coefficient, Xa.i, is 0.816. When a standard sample known to contain an analyte-to-interferent ratio of 5 1 is carried through the analysis, the error in determining the analyte is +6.3%. (a) Determine the apparent recovery for the analyte if Rj = 0. (b) Determine the apparent recovery for the interferent if Ra = 1 ... 

Mifflin, T. E. Andriano, K. M. Robbins, W. B. Determination of Penicillin Using an Immobilized Enzyme Electrode, /. Chem. Educ. 1984, 61, 638-639. 

Figure 5.7(b) Determining the number of steps and accelerating torque between each step... 

We wish to separate titanium dioxide particles from a water suspension. The method chosen is centrifugation. The unit is a continuous solid-bowl type with a bowl diamter of 400 mm, a length to width ratio of 3.0, and the unit operates at 2,000 rpm. The feed contains 18 % (weight basis) solids and is fed to the unit at 2,500 Liters/hr at a temperature of 95° F. The average particle size is 65 /tm. (a) Determine the amount of solids recovered per hour (b) Determine the solids concentration in the centrate (c) Determine the horsepower requirments for the centrifuge (d) Size a graviy settler to remove an additional 15 % of the solids. 

When dealing with water treatment applications you carmot avoid pipe flow calculations. We have a pipeline in which the throughput capacity of 500 Liter/sec. The flow is split into two pipelines and the inside diamter of the pipe is 350 mm. The length of the pipeline is 55 m. The entry loss is 0.70 and the exit loss is 1.00. There are two 45° bends and two 90° bends in the lines, (a) Determine the flow per pipe (b) determine the line velocity (c) determine the resulting hydraulic loss in meters. 

Mydlarz and Jones (1990a,b) determined agglomeration of potash alum in eontinuous MSMPR erystallization from aqueous solution and its effeet on slurry filterability (see Chapter 9). 

Pressure drop through line systems containing more than one pipe size can be determined by (a) calculating the pressure drop separately for each section at assumed flows, or (b) determining the R totals iox each pipe size sep>-arately, and then converting to one selected. size and using that for pressure drop calculations. For example, using... 

B. Determination of tellurium Procedure. The solution should contain not more than 0.2 g tellurium in 50 mL of 3M hydrochloric acid (ca 25 per cent by volume of hydrochloric acid). Heat to boiling, add 15 mL of a freshly prepared, saturated solution of sulphur dioxide, then 10 mL of a 15 per cent aqueous solution of hydrazinium chloride, and finally 25 mL more of the saturated solution of sulphur dioxide. Boil until the precipitate settles in an easily filterable form this should require not more than 5 minutes. Allow to settle, filter through a weighed filtering crucible (sintered-glass, or porcelain), and immediately wash with hot water until free from chloride. Finally wash with ethanol (to remove all water and prevent oxidation), and dry to constant weight at 105 °C. Weigh as Te. 

Determined by H-NMR and HPLC analyses. b Determined by H-NMR shift experiments using Eu(tfc),or Eu(hfc)3. c Determined by optical rotation. 

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