Stage liquids

After a single-stage liquid-liquid contact the phase remaining from the feed sohition (raffinate) can be contacted with another quantity of fresh extraction solvent. This crosscurrent extraction scVieme (Fig. 15-4) is an excellent laboratoiy procedure because the extrac t and raffinate phases can be analyzed after each stage to generate equihbrium data. Also, the feasibility of solute removal to lowTevels can be demonstrated. 

The same chemical mechanisms and driving forces presented for phenol-formaldehyde resins apply to resorcinol resins. Resorcinol reacts readily with formaldehyde to produce resins (Fig. 2) which harden at ambient temperatures if formaldehyde is added. The initial condensation reaction, in which A-stage liquid resins are formed, leads to the formation of linear condensates only when the resorcinol/formaldehyde molar ratio is approximately 1 1 [119]. This reflects the reactivity of the two main reactive sites (positions 4 and 6) of resorcinol [120]. However, reaction with the remaining reactive but sterically hindered site (2-positiori) between the hydroxyl functions also occurs [119]. In relation to the weights of resorcinol-formaldehyde condensates which are isolated and on a molar basis, the proportion of 4- plus 6-linkages relative to 2-linkages is 10.5 1. However, it must be noted that the first-mentioned pair represents two condensa-... 

Steady State Equilibrium Stage. Liquid-liquid extractions are used in many different... 

Figure 9-8I. Multipan MTS-109 two-stage liquid distributor. Used by permission of Nutter Engineering, Harsco Corp., Bull. CN-4.

Figure 9-8J. MTS-109 Multipan two-stage liquid distributor for optimum liquid distribution for uniform flow for random and structured packings for low to moderate liquid rates, less than 5 gpm/ft. Also used for redistributor. Used by permission of Nutter Engineering, Harsco Corp., Bull. TI-1, under license from The Dow Chemical Co., protected by U.S. Patents No. 4,472,325 4,808,350 5,013,491.

Fig. 119. Diagram of one- stage liquid-liquid extraction (1 - equilibrium curve, 2 - one-stage process)...

Figure 10A depicts a stacked Andersen eight-stage impactor with calibrated cut-off diameters of 9.0, 5.8, 4.7, 3.3, 2.1, 1.1, 0.7, and 0.4 pm and a lower absolute filter (0.22 pm) when operated at 28.3 L/min. Figure 10B depicts a four-stage liquid impinger with... 

Fig. 10 (A) Andersen eight-stage nonviable inertial sampler. (B) Four-stage liquid impinger.

Rectiflow A multi-stage, liquid-liquid extraction process for removing non-paraffinic components from lubricating oils. Furfural has been used as the solvent. Developed and used by the Shell Petroleum Company in the 1940s, subsequently abandoned. 

Final stage Liquid separated from solid... 

An improved procedure called "two-stage liquid-phase is described in Ref 4... 

Left Five-stage gas compressor Right Single-stage liquid pump Vh, Stroke volume Vr dead space Apa pressure amplitude per stage... 

In contrast, the single-stage liquid pumps exhibit a very large pressure-amplitude (A pa) which must be considered with regards to problems of failure if the components are loaded by pulsating internal pressure (see Section 4.1.4). 

Figure 1.4. NCE/NME progression scheme showing the various discovery stage liquid chromatography-mass spectrometry (LC-MS) and LC-tandem MS (LC-MS/MS) assays used for selecting NME/NCE to advance into development. (Reprinted with permission from Korfmacher, 2005.) (CARRS, Cassette accelerated rapid rat screening IV, Intravenous administration PO, Oral administration NCE, New chemical entity)...

This subsection describes the design of a contactor stage and how that design affects contactor operation. It will be shown when to add or avoid a particular feature. The discussion follows the flow of the two immiscible liquids through a contactor stage liquid entry, mixing, separation, and liquid exit. Finally, criteria for motor selection are reviewed. 

Leonard, R. A., A. A. Ziegler, R. A. Wigeland, et al. 1983. Operation with Three Liquid Phases in a Staged Liquid-liquid Contactor. Sep. Sci. Technol. 18, 1563-1579. 

In contrast to the description of distillation given earlier, which dealt with multistage distillation, flash distillation (Fig. 15) is carried out in a single stage. Liquid flows continuously through a heater, across a valve, and into a flash vessel. By heating the liquid and reducing its pressure across the valve, partial vaporization occurs in the flash... 

Stripping stages (Fig. 2.3a) concentrate the lees-volatile components in a liquid stream. A vapor recycle vaporizes ("strips ) the more-volatile components from the liquid. To generate the vapor recycle, heat is supplied to vaporize a portion of the bottom-stage liquid. This vapor recycle is termed boUup. 

The key ratio in the feed stage liquid should be as close as possible to the key ratio in the liquid portion of the feed flashed to tower pressure). 

Figure 3-33 Four Stage Liquid Crystal Tunable Filter.

A single-stage liquid/vapor separationfor tiie benzene(l)/etiiylbeiizene(2) system must produce phases of tiie following equilibrium compositions. For one of these sets, determine the T and P m tiie separator. What additional iiifomiation is needed to compute the relative amounts of liquid and vapor leaving tiie separator Assume that Raonlt s law applies. 

A process stream contains light species 1 and heavy species 2. A relatively pure liquid stream containing mostly 2 is desired, obtained by a single-stage liquid/vapor separation. Specifications on die equilibrium composition are X = 0.002 and yi = 0.950. Use data given below to determine T(K) and P(bar) for die separator. Assiune diat Eq. (10.5) applies die calculated P should validate diis assmnption. Data ... 

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