Leecture 3 - Test 1 stuff

Question 1

What are the In situ methods

Answer 1

• In Situ Spectroscopy
• In Situ X-ray and Neutron Scattering
• In Situ Microscopy
• In Situ Electrochemical Analysis
• In Situ Environmental Monitoring

Question 2

Explain In Situ Spectroscopy

Answer 2

• Techniques such as in situ UV-Vis spectroscopy, infrared ( IR ) spectroscopy, and nuclear magnetic resonance ( NMR ) spectroscopy are used to monitor chemical reactions, adsorption processes, and molecular changes in real-time
• For example, in situ NMR can be employed to observe chemical reactions as they occur inside an NMR tube

Question 3

Explain In Situ X-ray and Neutron Scattering

Answer 3

• X-ray and neutron scattering methods, such as X-ray diffraction (XRD) and small-angle neutron scattering (SANS), are used to study
  the structure and dynamics of materials and biomolecules in their native state
• In situ X - ray diffraction can track phase transitions in crystals, while SANS can monitor changes in macromolecular structures

Question 4

Explain In Situ Microscopy

Answer 4

• In situ microscopy techniques, including optical microscopy, electron microscopy (e.g., transmission electron microscopy or TEM), and atomic force microscopy (AFM), allow researchers to observe dynamic processes at the micro- and nanoscale
• For example, in situ TEM can capture real-time observations of nanomaterial growth

Question 5

Explain In Situ Electrochemical Analysis

Answer 5

• In situ electrochemical methods are used to study electrochemical reactions and processes
• Techniques like cyclic voltammetry and
  chronoamperometry provide insights into electrode kinetics, corrosion, and battery
  performance
• These methods are essential for battery research and development

Question 6

Explain In Situ Environmental Monitoring

Answer 6

• In environmental science, in situ sensors and
  monitoring devices are deployed in natural ecosystems or industrial settings to collect
  real-time data on parameters like temperature, pH, dissolved oxygen, and pollutant concentrations

Question 7

What are in situ methods

Answer 7

• Offer a dynamic and context-rich perspective in scientific research and engineering applications
• They provide insights that would be challenging or impossible to obtain through traditional ex situ (laboratory-based) methods, making them essential tools for understanding complex natural phenomena and optimizing various processes and
  technologies

Question 8

Hybrid processes

Answer 8

• Refers to the integration of multiple unit operations or process steps into a single, synergistic system
• Examples - membrane-assisted reactive distillation, membrane distillation for wastewater treatment, and combined heat and power (CHP) systems in the energy
  secto

Question 9

Multifunctional reactors

Answer 9

• Are innovative chemical reactors that combine multiple functions or unit operations within a single vessel
• Examples include mixing, reaction,
  separation, and heat exchange etc

Question 10

What makes up Multifunctional reactors

Answer 10

• Distillation
• In‐situ precipit
• Absorption
• Stripping
• Extraction
• Crystallization
• Pervaporation
• Per traction
• Supercrit extract
• Electrolysis
• Scorption
• Chromatography
• Partial condensation
• Zeolite membranes

Question 11

Explain New Reactor Concepts

Answer 11

1. Applications

• chemical manufacturing, petrochemicals, pharmaceuticals, and environmental
  engineering
• In the chemical industry
• In the pharmaceutical industry
• In environmental engineering

** Ultimate aim - improve efficiency, reduce costs, and enhance sustainability

Question 12

Microstructure reactors

Answer 12

• They offer enhanced heat and mass transfer, precise control of reaction conditions, and improved safety

2. Applications :

• Fine Chemicals
• Fuel Processing
• Biodiesel Production
• Polymerization
• Catalysis
• Wastewater Treatment
• Nanoparticle Synthesis
• Flow Chemistry

Question 13

What is desorption

Answer 13

The process by which a substance that was adsorbed (stuck/held) on a surface is released back into the surrounding phase (gas or liquid). It is essentially the reverse of adsorption

Question 14

Chemisorption

Answer 14

Is a chemical process where a molecule (adsorbate) forms a strong, often irreversible, chemical bond with a surface (adsorbent), typically involving electron sharing or transfer

Question 15

Alkene hydrogenation and mechanism

Answer 15

1. Adsorption: Hydrogen molecules are adsorbed onto the surface of the catalyst.
2. Activation : The hydrogen molecules on the catalyst surface are activated, often by breaking the H-H bond
3. Chemisorption : The alkene molecules chemisorb (bond) onto the catalyst surface
4. Hydrogenation : Hydrogen atoms from the activated hydrogen molecules add to the alkene’s carbon atoms, breaking the double bond and forming a single bond between the carbon atoms
5. Desorption : The hydrogenated alkane product desorbs from the catalyst surface
6. Regeneration : The catalyst may require regeneration by removing any adsorbed reactants or products before it can be used for further hydrogenations

Question 16

Explain Adsorption fully

Answer 16

• Is the surface phenomenon where molecules, ions, or atoms from a gas or liquid phase (the adsorbate) accumulate and adhere to the surface of a solid or liquid material (the adsorbent) rather than being absorbed throughout its bulk

Question 17

Explain desorption fully

Answer 17

• Is the process by which a substance that has previously been adsorbed (stuck) to a surface is released back into the bulk or gas phase
• It is the reverse of adsorption and occurs when the binding energy holding the substance to the surface is overcome
• Desorption can be triggered by increasing temperature, decreasing pressure, or the use of a solvent, and it is a key step in processes like thermal desorption and the regeneration of adsorbents

Question 18

Explain scorption

Answer 18

Is a broad term describing the process where a substance is taken up by another material, either by adhering to its surface (adsorption) or by being absorbed into its bulk (absorption)

Question 19

Name applications other than the ones below for nanostructured catalysts

Answer 19

1. Catalytic Converters

• In automotive catalytic converters to reduce emissions of harmful gases, such as nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbons, from vehicle exhaust

2. Photocatalysis

• Especially semiconductor nanoparticles like titanium dioxide (TiO2), are used in photocatalytic reactions for water splitting, pollutant degradation, and solar energy conversion

Question 20

Explain Nanostructured catalysts

Answer 20

• These catalysts with nano scale structure composed of nanoparticles or nanomaterials
• Important properties – high surface area, size, unique electronic properties
• Used in catalytic reactions, energy conversion, and environmental remediation