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Reactors agitated

The reaction is initiated with nickel carbonyl. The feeds are adjusted to give the bulk of the carbonyl from carbon monoxide. The reaction takes place continuously in an agitated reactor with a Hquid recirculation loop. The reaction is mn at about atmospheric pressure and at about 40°C with an acetylene carbon monoxide mole ratio of 1.1 1 in the presence of 20% excess alcohol. The reactor effluent is washed with nickel chloride brine to remove excess alcohol and nickel salts and the brine—alcohol mixture is stripped to recover alcohol for recycle. The stripped brine is again used as extractant, but with a bleed stream returned to the nickel carbonyl conversion unit. The neutralized cmde monomer is purified by a series of continuous, low pressure distillations. [Pg.155]

The alcoholysis reaction may be carried out either batchwise or continuously by treating the triglyceride with an excess of methanol for 30—60 min in a well-agitated reactor. The reactants are then allowed to settle and the glycerol [56-81-5] is recovered in methanol solution in the lower layer. The sodium methoxide and excess methanol are removed from the methyl ester, which then maybe fed directiy to the hydrogenolysis process. Alternatively, the ester may be distilled to remove unreacted material and other impurities, or fractionated into different cuts. Practionation of either the methyl ester or of the product following hydrogenolysis provides alcohols that have narrow carbon-chain distributions. [Pg.446]

The synthesis of the high molecular weight polymer from chlorotrifluoroethylene [79-38-9] has been carried out in bulk (2 >—21 solution (28—30), suspension (31—36), and emulsion (37—41) polymerisation systems using free-radical initiators, uv, and gamma radiation. Emulsion and suspension polymers are more thermally stable than bulk-produced polymers. Polymerisations can be carried out in glass or stainless steel agitated reactors under conditions (pressure 0.34—1.03 MPa (50—150 psi) and temperature 21—53°C) that require no unique equipment. [Pg.394]

Manufacture is either by reaction of molten sodium with methyl alcohol or by the reaction of methyl alcohol with sodium amalgam obtained from the electrolysis of brine in a Castner mercury cell (78). Both these methods produce a solution of sodium methylate in methanol and the product is offered in two forms a 30% solution in methanol, and a soHd, which is a dry, free-flowing white powder obtained by evaporating the methanol. The direct production of dry sodium methylate has been carried out by the introduction of methanol vapors to molten sodium in a heavy duty agitating reactor. The sohd is supphed in polyethylene bags contained in airtight dmms filled in a nitrogen atmosphere. [Pg.26]

Process. A typical indirect hydration process is presented in Eigure 1. In the process, propylene reacts with sulfuric acid (>60 wt%) in agitated reactors or absorbers at moderate (0.7—2.8 MPa (100—400 psig)) pressure. The isopropyl sulfate esters form and are maintained in the Hquid state at 20—80°C. Low propylene concentrations, ie, 50 wt %, can be tolerated, but concentrations of 65 wt % or higher are preferred to achieve high alcohol yields. Because the reaction is exothermic, internal cooling coils or external heat exchangers are used to control the temperature. [Pg.107]

Table 5. Representative Dimensionless Groups for Agitated Reactors... Table 5. Representative Dimensionless Groups for Agitated Reactors...
Chromium Removal System. Chlorate manufacturers must remove chromium from the chlorate solution as a result of environmental regulations. During crystallization of sodium chlorate, essentially all of the sodium dichromate is recycled back to the electrolyzer. Alternatively, hexavalent chromium, Cr, can be reduced and coprecipitated in an agitated reactor using a choice of reducing agents, eg, sodium sulfide, sulfite, thiosulfate, hydrosulfite, hydrazine, etc. The product is chromium(III) oxide [1333-82-0] (98—106). Ion exchange and solvent extraction techniques have also... [Pg.499]

A VCM (vinyl chloride monomer) production unit uses three vertically mounted agitated reactors for the polymerization of vinyl chloride. Crude material balances infer about 8 to 10% monomer losses. Describe how you would go about assessing whether these losses are due to leaks such as fugitive air emissions. Be specific in recommending procedures and instruments. [Pg.147]

In contrast, composting processes utilize a mixture of solids and yard waste under controlled environmental conditions to produce a disinfected, humus-like product. Three common composting systems are a horizontal agitated reactor, a horizontal nonagitated reactor, and an aerated static pile system (nonproprietary). Compost can be marketed as a soil conditioner in competition with such products as peat, soil, and mulch. Although a large potential market exists, significant effort is required to penetrate this market. Yard waste revenue of 6.50/m (S5/yd ) and product revenue of 2.00/m ( 1.50/yd ) appear to be reasonable market values based on various studies reported on the Web. [Pg.572]

Samant and Ng [28] compared various scale-up rules for agitated reactors. They suggested that a scale-up rule of power per unit volume and constant average residence time (where the power per unit volume and average residence time cannot be increased) is the most suited in many operations. However, this still may not improve or preserve the performance of the systems. Therefore, adequate consideration must be given to a tradeoff between performance and operating constraints. [Pg.597]

Figure 8.19 Transient pH, ( -potential and calcium ion concentration in an agitated reactor Jones etal., 1992a)... Figure 8.19 Transient pH, ( -potential and calcium ion concentration in an agitated reactor Jones etal., 1992a)...
Although studied for agitated reactors, the phenomena of thermal ignition are probably of more interest in the non agitated high conversion reactors such as the polymerize-... [Pg.76]

Mixing Models. The assumption of perfect or micro-mixing is frequently made for continuous stirred tank reactors and the ensuing reactor model used for design and optimization studies. For well-agitated reactors with moderate reaction rates and for reaction media which are not too viscous, this model is often justified. Micro-mixed reactors are characterized by uniform concentrations throughout the reactor and an exponential residence time distribution function. [Pg.297]

MASS TRANSFER AND CHEMICAL REACTION ASPECTS CONCERNING ACETALDEHYDE OXIDATION IN AGITATED REACTOR... [Pg.221]

Y. T, Shah, Design Parameters for Mechanically Agitated Reactors Mooson Kwauk, Particulate Fluidization An Overview... [Pg.345]

Agitated reactor (possibly with catalyst particles) Catalytic and noncatalytic Reactions, polymerizations (special agitator required) High transport rates, convenient to operate, easy variation of parameters, most versatile Catalyst erosion... [Pg.307]

Reviews on mechanically agitated reactors have been presented recently by Shah (1991) and Carpenter (1997). The latter discussed the construction of such reactors and the influence of design and operational parameters on the behaviour of the phases and possible interaction between them in detail. [Pg.352]

Stirred tank (agitated) reactors consist of a tank fitted with a mechanical agitator and a cooling jacket or coils. They are operated as batch reactors or continuously. Several reactors may be used in series. [Pg.484]

A jacketed, agitated reactor consists of a vertical cylinder 1.5 m diameter, with a hemispherical base and a flat, flanged, top. The jacket is fitted to the cylindrical section only and extends to a height of 1 m. The spacing between the jacket and vessel walls is 75 mm. The jacket is fitted with a spiral baffle. The pitch between the spirals is 200 mm. [Pg.780]

Studies in Table 1 refer to different types of reactors stirred tank (mechanically agitated reactors and rotary reactors), fixed bed and fluidized bed. Figure 2 reports an outline of the most common reactor typologies. The reactors may be operated... [Pg.109]

Equation (3-14) is similar to Equation (3-12) for the well-agitated reactor, where the ATmax is given as RT /Ea in which T is the temperature of the stirred reaction mass. A version of Equation (3-14) which applies to unstirred liquids without convection is ... [Pg.114]

Continuous stirred tank reactor (CSTR) an agitated tank reactor with a continuous flow of reactants into and products from the agitated reactor system ideally, composition and temperature of the reaction mass is at all times identical to the composition and temperature of the product stream. [Pg.228]

Another way of running this reaction is to feed the agitated reactor continuously at such a rate that we get 90% conversion of butynediol. How do these two processing rates compare in the long term Give your answer B0,continuous/ B0, batch Assume that the liquid feed composition, gas composition and pressure, mass transfer and chemical rates are the same in both batch and continuous operations. [Pg.519]

Lime Reactor The efflnent from the EDV system is pumped to an agitated reactor vessel where the EDV efflnent is reacted with lime to form calcium sulfite and active sodium species via the following reactions ... [Pg.309]

Agitated tank reactors Batch agitated reactor This is a batch stirred tank reactor. For liquid-solid systems, the liquid is agitated by a mechanical apparatus (impeller) and the reactor is of tank shape. For gas-solid systems, the gas is agitated and rapidly circulated through a fixed-bed of solids. This reactor is basically an experimental one used for adsorption, ion exchange, and catalysis studies. [Pg.74]


See other pages where Reactors agitated is mentioned: [Pg.34]    [Pg.34]    [Pg.517]    [Pg.44]    [Pg.828]    [Pg.135]    [Pg.221]    [Pg.301]    [Pg.340]    [Pg.387]    [Pg.387]    [Pg.944]    [Pg.18]    [Pg.32]    [Pg.438]    [Pg.660]    [Pg.296]    [Pg.131]    [Pg.143]    [Pg.80]    [Pg.211]    [Pg.124]   
See also in sourсe #XX -- [ Pg.37 ]




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Agitated cell reactor

Agitated polymerization reactors

Agitated reactors calculation

Agitated reactors hydrodynamics

Agitated reactors impeller power

Agitated reactors interfacial area

Agitated reactors mass transfer coefficient

Agitated reactors mixing

Agitated reactors power dissipation

Agitated reactors solid-liquid, mixing

Agitated slurry reactor

Agitated slurry reactor modeling

Agitated tank reactor

Agitation

Agitators

Batch reactor agitation

Bubble reactors, mechanically agitated

Continuous stirred tank reactors agitators/impellers

Equipment Agitated cell reactor

Gas-liquid mixing, in agitated reactors

Liquid Mixing in Agitated Reactors Richard V. Calabrese, ouglas E. Leng, and Piero M. Armenante

Multistage mechanically agitated reactors

Reactor 1 Agitated Mini-autoclaves

Reactor agitation

Reactor agitation

Reactor agitator failure

Reactor with Agitators

Reactor with multiple-impeller agitator

Reactors batch agitated

Reactors, agitated tank backmix

Reactors, agitated tank backmixing

Reactors, agitated tank batch

Slurry reactor mechanically agitated

Slurry reactor multiple-agitator

Three-phase slurry reactors agitated tanks

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