Polymerization Process and Catalysts Quiz
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Questions and Answers

What is the recommended pH for the reactor before adding vazo?

  • 500
  • 900
  • 1000
  • 700 (correct)

    • Which reducer is primarily used to initiate the polymerization reaction?

  • Sodium Metabisulfate
  • Monr's Salt (correct)
  • Sodium Sulfite
  • Sodium Persulfate

    • What is the minimum reaction time for the TBHP thermal catalyst?

  • 1 minute
  • 30 seconds (correct)
  • 5 minutes
  • 10 seconds

    • What is one of the byproducts formed from the thermal degradation of vazo 64?

    <p>TMSN</p> Signup and view all the answers

    How does increasing the amount of redox catalyst affect the reaction kinetics?

    <p>Results in faster kinetics</p> Signup and view all the answers

    What is the impact of copper on the polymerization process?

    <p>Inhibits polymerization</p> Signup and view all the answers

    What is the purpose of the cyclone in the process?

    <p>To capture good products for further processing</p> Signup and view all the answers

    What must be done to preserve the stability of thermal catalysts?

    <p>Store in cold storage</p> Signup and view all the answers

    What is the specific gravity of the solution to be weighed in the salt concentration procedure?

    <p>500</p> Signup and view all the answers

    Which component is used as a neutral charge in the charges section?

    <p>Acrylamide</p> Signup and view all the answers

    What is the boiling point condition mentioned in the R9 Tenportive section?

    <p>95° Before Boiling Point</p> Signup and view all the answers

    What is the purpose of using purified water mentioned in the REDOX section?

    <p>To ensure no minerals interfere with the catalyst</p> Signup and view all the answers

    How long should the line be flushed during the salt concentration procedure?

    <p>5 seconds</p> Signup and view all the answers

    What effect does chelated iron have on reactions compared to unchelated iron?

    <p>Acts as a catalyst and accelerates the reaction</p> Signup and view all the answers

    Which method is typically used for hydrolysis in reactions?

    <p>Caustic substances</p> Signup and view all the answers

    What is the primary reason for poor solubility in polymers?

    <p>Excessive temperatures during drying and polymerization</p> Signup and view all the answers

    What happens to a polymer chain during hydrolysis?

    <p>It converts to an anionic acrylic acid tail</p> Signup and view all the answers

    What is the concern if the reaction temperature exceeds 100°C?

    <p>Water converts to steam and expands the gel</p> Signup and view all the answers

    What is the consequence of high crosslinking in polymers?

    <p>Decreased solubility</p> Signup and view all the answers

    What effect does running reactions too quickly have on the viscosity level?

    <p>It causes a low UL viscosity.</p> Signup and view all the answers

    At what temperature do most reactions start?

    <p>O°C</p> Signup and view all the answers

    What characterizes 'branching' in polymer chemistry?

    <p>Increases viscosity without raising molecular weight</p> Signup and view all the answers

    What is defined as the unreacted or un-polymerized monomer molecules in polyacrylamide gel?

    <p>Free monomer</p> Signup and view all the answers

    Which ingredient is NOT mentioned as part of the initial mix for polymerization in the reactor?

    <p>Acetone</p> Signup and view all the answers

    What happens if the temperature in the reactor peaks above the boiling point of water?

    <p>The gel can be forced violently out of the reactor.</p> Signup and view all the answers

    What causes the primary characteristics of the polymer product, charge, and molecular weight?

    <p>The polymerization process.</p> Signup and view all the answers

    What is the result of adding too much monomer and not enough water in the reactor?

    <p>The reactor peaks at too high of temperature.</p> Signup and view all the answers

    What might be indicated by differences in temperature readings from reactor temperature probes?

    <p>Malfunctioning equipment or probes.</p> Signup and view all the answers

    What is a consequence of longer polymer chains in the product?

    <p>They make drying the polymer harder without causing solubility problems.</p> Signup and view all the answers

    What triggers the initiation step in polymerization?

    <p>The addition of the reducer from redox</p> Signup and view all the answers

    What is a consequence of having poor sparge pressure or flow-rate?

    <p>Inadequate mixing of catalyst</p> Signup and view all the answers

    Which of the following is NOT a cause of termination in polymerization?

    <p>Excessive heat in the reactor</p> Signup and view all the answers

    What is the primary role of sparging in polymerization?

    <p>To displace oxygen in the reactor</p> Signup and view all the answers

    What is the impact of excess Versenex 80 in a reaction?

    <p>It chelates copper and iron completely</p> Signup and view all the answers

    What problem can arise if a leak occurs in the nitrogen line during sparging?

    <p>Oxygen entry causing initiation issues</p> Signup and view all the answers

    What happens if a solution of acrylamide is supplied with copper metal in it?

    <p>Premature initiation is inhibited</p> Signup and view all the answers

    What occurs during the propagation phase of polymerization?

    <p>Thermal catalysts drive the chain reaction</p> Signup and view all the answers

    What is the primary purpose of the gel hopper?

    <p>To maintain a consistent flow of product to the granulator</p> Signup and view all the answers

    What happens when the gel hopper dips below the set point?

    <p>The automatic sequences will refill the gel hopper</p> Signup and view all the answers

    What could indicate a problem if a normally easy-to-pre-grind product is hard to grind?

    <p>The gel is too cold or the UL is too high</p> Signup and view all the answers

    How does the pre-grinder facilitate the grinding process?

    <p>By tearing the gel into smaller pieces using screws</p> Signup and view all the answers

    What is a safety concern to keep in mind when working with the gel hopper?

    <p>Entering the gel hopper without following confined space procedures</p> Signup and view all the answers

    What could happen if the feed to the granulator is inconsistent?

    <p>Non-uniform drying</p> Signup and view all the answers

    What is the role of the grinding aid, Lubchopnos PK 455?

    <p>To make gel easier to grind</p> Signup and view all the answers

    What is a sign of malfunctioning load cells on the gel hopper?

    <p>Incorrect weight reading in the DCS</p> Signup and view all the answers

    Study Notes

    Process Overview

    • Raw materials are prepped before entering the reactor.
    • Reactor operation involves mixing, reactions, and temperature control.
    • Reaction times vary, depending on molecular weight.
    • Gel exiting the reactor is processed and cooled.

    Catalyst Mix Times

    • Vazo is prepared via a 30-minute spin.
    • AZDN (catalyst) mix times: 5 minutes
    • VerSenex (co-reactant) mix times: 3 minutes

    Reduction Reactions

    • Oxidizer: Sodium Persulfate
    • Reducers: Mohr's Salt, Tert-Butyl Peroxide (CTBHP), Potassium Bromate, Sodium Metabisulfate (MBS), Sodium Sulfite, Sodium Formaldehyde Sulfoxylate (CNAFS)

    PH and Neutralization

    • PH is 700
    • Neutralization occurs in the reaction process.

    Viscosity Control and Molecular Weight

    • Hypo is used to control molecular weight.
    • Different polymers have different molecular weights.

    Tank Sizes and Weights

    • DTANK - 26,000 kg
    • 3,000 L reactor used.
    • 3,500 mL reaction volume.

    Thermal Degradation

    • Thermal catalyst degradation produces toxic byproducts, like TMSN.
    • Different catalysts have different degradation rates at various temperatures

    Polymerization Steps & Inhibitor

    • Polymerization begins when the reducer is added.
    • Oxygen inhibits reaction hence, nitrogen sparging is crucial.
    • Reaction time depends on molecular weight.

    Auto Initiation

    • Issues can arise with improper dissolution tank reaction control.
    • Left-over catalyst can trigger auto-initiation.
    • Catalyst mixing and inconsistent rates lead to erratic reaction curves.

    ###Chelating Agents

    • Versenex 80 is used as a chelating agent.
    • Versenex 80 is used to control reactions by binding transition metals
    • Excessive Versenex 80 can also be used as a catalyst

    Product Solubility

    • Solubility is a product feature affected by temperature & pressure.
    • High temperatures lead to poor solubility.
    • Excessive branching decreases solubility.

    Hydrolysis

    • Involves water reacting with a substance.
    • Hydrolysis can result in higher charges on polymer.
    • Temperature is a crucial factor to control during hydrolysis reaction

    Kinetics

    • Reaction rate depends on temperature, measured over time using X-Y graphs.
    • Reaction time scales with molecular weight of polymer.

    Free Monomer

    • Free monomers are unreacted monomers.
    • Free monomer levels affect polymer quality.

    Reactor Operation

    • Reactor operation involves charging, stirring, reacting, and dumping gel.
    • Specific temperature and time parameters optimize the reaction

    Reactor Trouble Shooting

    • Reactor liners can wear out, resulting in poor reaction control; electro-polishing or Teflon lining helps.
    • High temperatures could indicate problems.
    • Difference in temperatures between probe or tank could signal poor probe calibration.

    Gel Hopper

    • Consistent feed to granulator via weight control mechanism.
    • Automatic filling process regulated by weight measurements in the tank.
    • Safety procedures for hopper entry are crucial.

    Pre-Grinder

    • Pre-grinding breaks down the gel into smaller pieces for even drying.
    • Product consistency depends on gel hardness and consistency.
    • Grinding is difficult for products with high cationic content

    Post-Treatment

    • Post-treatment (e.g., sodium sulfate) reacts the monomer.
    • Prevents issues with post-reaction.
    • Helps achieve even mixing in the gel.

    Other notes

    • Specific chemicals (e.g. span 80, Vazo, TBHP, etc.) are used in different stages of the process.
    • Various pieces of equipment and materials are used for the process, such as pumps, tanks, and measuring instruments.
    • Multiple steps include mixing, reacting, and measuring or adjusting parameters.
    • Different process parameters or process problems are outlined throughout the notes.
    • Specific values for PH, temperature, molecular weights, time values, etc., are included in the notes along with specific chemical or equipment names.

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    Polymerization Reactions PDF

    Description

    Test your knowledge on the polymerization process, including pH levels, reducers, and thermal catalysts. Understand the role of various components like vazo, copper, and the cyclone in reaction kinetics. This quiz covers essential concepts that are crucial for mastering polymer engineering.

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