CHEM F337: Green Chemistry Lecture 08
28 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the starting material used in the green route to styrene production?

  • Benzene
  • Xylene (correct)
  • Toluene
  • Ethylene
  • What is the primary concern associated with polyacrylates?

  • Degradability (correct)
  • Chemical stability
  • Toxicity of materials
  • Cost of production
  • Which catalyst is used in the traditional route for styrene production?

  • Alumina catalyst
  • Fe-oxide catalyst (correct)
  • Nickel catalyst
  • Zeolite based catalyst
  • Which of the following is a key characteristic of polyaspartates compared to polyacrylates?

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

    What is one of the by-products generated in the traditional route for allyl alcohol production?

    <p>Hydrochloric acid</p> Signup and view all the answers

    What is the source material for synthesizing polyaspartates?

    <p>L-aspartic acid</p> Signup and view all the answers

    What is the overall selectivity to styrene in the green route using toluene and methanol?

    <p>60%</p> Signup and view all the answers

    Which application is NOT mentioned for polyacrylates?

    <p>Electrical insulators</p> Signup and view all the answers

    In the green route to allyl alcohol, which reactants are used in the first step?

    <p>Propylene, acetic acid, and oxygen</p> Signup and view all the answers

    Which property of polyaspartates makes them a suitable alternative to polyacrylates?

    <p>Similar performance characteristics</p> Signup and view all the answers

    What is a notable property of polyaspartate?

    <p>It is biodegradable.</p> Signup and view all the answers

    What are the components used to synthesize polyaspartate?

    <p>Aspartic acid and NaOH.</p> Signup and view all the answers

    Which organization awarded the Donlar Corporation for its green chemistry innovations?

    <p>Presidential Green Chemistry Challenge.</p> Signup and view all the answers

    What type of award did the Donlar Corporation receive in 1996?

    <p>Presidential Green Chemistry Challenge Award.</p> Signup and view all the answers

    What chemical reaction occurs during the synthesis of polyaspartate?

    <p>Condensation of aspartic acid.</p> Signup and view all the answers

    In which category did the Donlar Corporation win the Presidential Green Chemistry Challenge Award?

    <p>Small business category.</p> Signup and view all the answers

    What role does NaOH play in the synthesis of polyaspartate?

    <p>It serves as a catalyst.</p> Signup and view all the answers

    What is the relationship between polyaspartate and aspartic acid?

    <p>Polyaspartate is a polymer derived from aspartic acid.</p> Signup and view all the answers

    What was the main disadvantage of the Boots process for ibuprofen in the 1960s?

    <p>It generated unwanted chemical waste.</p> Signup and view all the answers

    How many steps did the Hoechst-Celanese process use for ibuprofen synthesis?

    <p>3 steps</p> Signup and view all the answers

    What type of linkage was primarily utilized in Donlar's polyaspartates manufacturing facility?

    <p>70% α-linkage</p> Signup and view all the answers

    In what year did Boots win the Queens Award for Technical Achievement?

    <p>1987</p> Signup and view all the answers

    Which award did the Hoechst-Celanese process win in 1991?

    <p>Kirkpatrick Award</p> Signup and view all the answers

    What temperature range is optimal for microwave processing in high-temperature water reactions?

    <p>100–200 °C</p> Signup and view all the answers

    What is a limitation of pure water in microwave heating as temperatures increase?

    <p>It is difficult to heat above 130 °C.</p> Signup and view all the answers

    What percentage of atom efficiency does the Hoechst-Celanese process claim for its steps?

    <p>100% Atom efficient</p> Signup and view all the answers

    What was a major characteristic of the Boots process compared to the Hoechst-Celanese process?

    <p>More eco-friendly</p> Signup and view all the answers

    What is a common feature of the processes for synthesizing ibuprofen mentioned in the content?

    <p>Both reduced chemical waste.</p> Signup and view all the answers

    Study Notes

    Case Studies - Green Chemical Products

    • Styrene Production

      • Traditional two-step method starts with benzene and ethylene for ethylbenzene, followed by dehydrogenation.
      • Step II uses Fe-oxide catalyst and K2CO3 promoter, achieving 65% conversion and 95-97% selectivity to styrene.
      • Green route utilizes xylene as a less toxic starting material, converting to styrene via toluene and methanol at >400 °C using a proprietary zeolite catalyst.
      • Overall selectivity to styrene in the green process is approximately 60% at 1 atm pressure, making it the cheapest route.
    • Allyl Alcohol Production

      • Traditional method involves alkaline hydrolysis of allyl chloride, producing hydrochloric acid as a by-product.
      • The Shell process uses NaOH, resulting in significant NaCl generation.
      • Green synthesis avoids chlorine by processing propylene, acetic acid, and oxygen in two steps: acetoxylation followed by hydrolysis.
      • Acetic acid from hydrolysis can be reclaimed for reuse, providing a sustainable cycle.
      • An alternative method uses glycerol reacting with formic or oxalic acids.
    • Thermal Polyaspartate as an Alternative to Polyacrylates

      • Polyacrylates are widely used in products like paints, fibers, resins, and cosmetics but raise concerns about degradability.
      • Polyaspartates, developed by Donlar Inc., are biodegradable biopolymers derived from L-aspartic acid with no waste by-products.
      • Exhibit similar properties to polyacrylates, making them suitable for applications as dispersants and superabsorbers.
      • Donlar Corporation won the 1st Presidential Green Chemistry Challenge Award in 1996 and opened the largest polyaspartates facility in 1997.

    Green Reaction Conditions

    • Ibuprofen Production
      • The Boots process from the 1960s involved 6 steps with stoichiometric reactions, leading to chemical waste and high costs.
      • Boots was recognized with the Queens Award for Technical Achievement in 1987 for their contributions.
      • Hoechst-Celanese developed a more efficient green chemistry method with only 3 catalytic steps, achieving 100% atom efficiency.
      • The HC process received the Kirkpatrick Award in 1991 for its innovative use of catalytic processes over traditional stoichiometric methods.

    Green Modes of Activation

    • High-temperature water reactions (100–200 °C) are optimal for microwave processing in sealed vessels.
    • Challenges arise as pure water's absorbance of microwave energy decreases above 130 °C, complicating heating efforts.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Description

    Dive into the case studies of green chemical products, focusing on styrene production. This lecture explores traditional and innovative methods, including the use of Fe-oxide catalysts. Learn about the efficiency and environmental impact of these processes.

    More Like This

    Green Chemistry
    10 questions

    Green Chemistry

    EffortlessIsland avatar
    EffortlessIsland
    Green Chemistry Quiz
    10 questions

    Green Chemistry Quiz

    CompliantPelican avatar
    CompliantPelican
    Green Chemistry Principles
    12 questions
    Green Chemistry Principles
    45 questions
    Use Quizgecko on...
    Browser
    Browser