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AgendaAgenda
• What is Chemistry?• Chemistry in process industry• Organic and Inorganic• Chemical and Physical Properties• Terminology• Reactions• Chemical Formulas, Calculating Mass• Acid, Base, pH• Hydrocarbons• Review
Chemistry in the Process Chemistry in the Process IndustryIndustry
• Chemistry – the science that describes matter, its chemical and physical properties, the chemical changes it undergoes, and the energy changes that accompany those processes.
Chemistry in the Process Chemistry in the Process IndustryIndustry
• Through chemistry, scientists and process technicians are able to understand various elements and compounds, their properties, and how they interact with one another in the presence of heat, cold, catalyst, and other variables.
• By understanding these principles, the process industries are able to produce better products and safer processes.
Chemistry in Process Chemistry in Process IndustryIndustry
• How Chemistry Applies to Process Tech– Turning raw materials into products– Proper management of waste– Understand chemistry concepts that
occur during manufacturing process– Understand terminology– Understand concepts to troubleshoot
problems and improve quality, efficiency
• Atoms – smallest particle of an element that retains the properties of that element– Protons – positively charged subatomic particle found in
the nucleus of an atom– Neutrons – subatomic particle found in the nucleus of
an atom that has no charge– Electrons – negatively charged subatomic particle found in
orbiting the nucleus of an atom-- Valence Electrons – outermost electrons which
provide links for bonding
• Molecule – neutral chemically bonded groups of atoms that act as a unit
Structure of MatterStructure of Matter
• Atomic Number – the number of protons in the nucleus of an atom of an element
• Atomic Mass (Molecular Weight) – weighted average of the masses of the isotopes of an element predominantly from masses of protons & neutrons
• Determining Molecular Weight – – Add all masses of each element. Remember
to multiply if more than 1 present.
Structure of Matter Structure of Matter (Continued)(Continued)
Organic and InorganicOrganic and Inorganic
• Chemistry – science that deals with the composition, behavior, and transformation of matter
• Organic – carbon based
– Hydrocarbon – contains only hydrogen and carbon
• Inorganic – no carbons
– Such as salts, acids, bases, metals– Many agricultural products
Physical PropertiesPhysical Properties
• Density – mass (weight) per unit volume
• Specific Gravity – comparison of density to that of water for solids and liquids and to air for gases
• Hardness – ability of one substance to scratch/mark another
• Odor – smell of substance
• Color – optical sensation produced by effect of light waves stiking surface
Chemical PropertiesChemical Properties
• The ability of a substance to form new substances under given conditions.
• A listing of all chemical reactions of a substance and the conditions under which the reactions can occur.
Reactivity of a Reactivity of a ChemicalChemical
• The ability of a substance to form new substances under given conditions
• A listing of all chemical reactions of a substance and the conditions under which the reactions can occur
Types of BondsTypes of Bonds
• Ionic – metal and non-metal. Electrons are transferred
• Covalent – non-metals. Electrons are shared
• Metallic – metal to metal. Electrons free flow
Terminology Terminology
• Matter – anything occupying space that has mass
• Element – simplest form of matter
• Compound – pure substance made up of elements that are chemically combined
• Mixture - mixed together, but no chemical reaction
• Solution - a homogenous mixture of 2 or more substances in a single phase (usually liquid). Solute and solvent.
Terminology (Continued)Terminology (Continued)
• Solvent – substance that dissolves• Solute – substance that is dissolved
– Solubility : how well solvent dissolves the solute
• Freezing Point• Melting Point
Terminology (Continued)Terminology (Continued)
• Boiling Point– When vapor pressure of liquid
equals system pressure– As vapor pressure increases, boiling
point decreases– As pressure increases, so does
boiling point– The higher the vapor pressure the
more easily a material evaporates
Terminology (Continued)Terminology (Continued)
• Homogenous– Same throughout– Can’t tell one part of mixture from another
• Heterogeneous– Different
• Equilibrium– Rate of reactants forming products = rate
of products forming reactants• Anion – atom or group of atoms with negative
charge• Cation - atom or group of atoms with positive
charge
Chemical ReactionsChemical Reactions
• Chemical Reactions– Endothermic – needs/absorbs heat– Exothermic – gives off heat– Neutralization – acid + base
salt + water– Combustion –
• fuel + oxygen combustion products + heat + light
– Replacement – removes minerals from water
Chemical Reactions are Chemical Reactions are Affected ByAffected By
• Heat --- increases molecular activity and reaction rate (rates double with each 10°)
• Pressure – slows molecular movement and changes boiling point
• Surface Area – solids• Concentration of liquid and gas
components• Flow Rates of reactants and products
Chemical ReactionsChemical Reactions
• Catalyst– Helps a reaction go at a lower
temp or increases rate of reaction
– Is not consumed in the reaction
Types of CatalystsTypes of Catalysts
• Adsorption – solid that attracts and holds reactant molecules so more collisions can occur. Also stretches bonds of reactants making them easier to break, which requires less energy.
Types of CatalystsTypes of Catalysts
• Intermediate – attaches to reactant molecules and slows it down so collisions can occur
• Inhibitor – decreases reaction rate• Poisoned / Spent – no longer
functions due to contamination or has been used up– Some can be regenerated
Chemical EquationsChemical Equations
• Like a recipe
• Must be balanced (same number of atoms of each element in reactants as products
2H2 + O2 2H2O
reactants products
Mass RelationshipsMass Relationships
• Allows us to take a balanced equation and use it to determine the actual mass/weight needed for reactants and how much product can be produced
Mass Relationships - StepsMass Relationships - Steps
• Find molecular weight of each element on periodic table (AMUs, but represent grams, pounds, etc.)– Example H = 1.008 O = 16.00
• Multiply by number of atoms (if > 1)– Example H x 2 = 2.016
• Total these up to determine actual weight of entire molecule
– Example H2O = 2.016 + 16.00 = 18.016
• Note how reactant mass = product mass
Mass Relationships - StepsMass Relationships - Steps
• Determine how many moles (amounts) of a reactant are needed to produce a set amount of product– Example N2 + 2O2 2NO2
– So you need 1 mole of N2 and 2 moles of O2 to make 2 moles of NO2
Mass Relationships - StepsMass Relationships - Steps
• Determine the relative volume of reactant or product you have– Example if you only have 16 pounds of
O, you only have 0.25 volume (16/64)
• Multiply the relative volume by the amount of product you can make– Example – 0.25 x 2NO2 = 0.5 volume
of NO2
Mass Relationships - StepsMass Relationships - Steps
• Multiple the volume you can make by the molecular weight of material– Example – 0.5 volume x 46 * = 23 kg,
lbs, tons
N = 14.00 kg, lbs, tonsO = 16.00 x 2 = 32.00 kg, lbs, tons
* 46.00 kg, lbs, tons
Material BalancesMaterial Balances
• Method used to determine the exact amount of reactants needed to produce the specified products in the quantity desired
• Steps– Determine the weight of each molecule– Ensure reactant total weight equals product
total weight– Determine relative number of reactant atoms
or ions
Percent by Weight Percent by Weight SolutionsSolutions
• Weight of solute (material that is dissolved) is taken in relationship to entire solution
• 650 pound barrel has 10% catalyst solution
– 650 lb x 0.10 (percent as decimal) = 65 lbs
Acid, Base and pHAcid, Base and pH
• pH – measurement of hydrogen ions in solution
• Acid (pH > 0 and < 7)– Sour taste– Vinegar, Hydrocholoric Acid, Hydrofluoric Acid
• Base (pH > 7 and < 14)– Bitter taste, slippery
• Alkaline• Caustic –pungent odors
– Lye, sodium hydroxide, caustic soda• Neutral – pH = 7• The stronger the acid or base the more
hazardous to body tissue and metal
HydrocarbonsHydrocarbons
• Compound that contains both hydrogen and carbon
• Fossil fuels – oil & natural gas, and their refined products (gasoline, ethylene)
HydrocarbonsHydrocarbons
• Major groups– Alkanes – single covalent bond (methane,
propane, ethane, etc)– Olefins – not naturally occurring. Produced by
cracking oil. At least one double bond (hence the high energy when used)
• Alkenes – double bonds (ethylene, propylene)• Alkyne – triple bonds (acetylene – only one used
widely)• Cycloalkane – contains a ring or cycle of carbons• Aromatic – contains at least one highly unsaturated
six-carbon ring
Aromatic HydrocarbonsAromatic Hydrocarbons
• Include both hydrocarbons and compounds that cannot be classified as hydrocarbons
• Most common - benzene
AlcoholsAlcohols
• Compounds that contain OH goups connected to an alkyl carbon.– Ethanol – commonly referred to as
grain alcohol since often produced from corn, rye, wheat, molasses (from sugar cane), grapes and potatoes. • Becoming popular as gasoline additive or
main fuel.
AlcoholsAlcohols
• Methanol – referred to as wood alcohol, because it was originally derived from wood. – Now produced by subjecting H to
CO3 at high temp. in presence of catalyst.
– Used as solvent in paints, varnishes, production of formaldehyde, cleaners.
AlcoholsAlcohols
• Isopropyl Alcohol – most common is rubbing alcohol used externally for cooling skin, disinfect cuts, cosmetic solvent
PhenolsPhenols
• Similar to alcohols, but have an OH group connected directly to an aromatic ring.
• Used in antiseptics, dyes, aspirin, and at one time throat lozenges
Ethylene GlycolEthylene Glycol
• Highly reactive ethylene oxide is reacted with water
• Commonly used as antifreeze in vehicle radiators because of unique abiltiy to lower freezing point of water.
• Also has higher boiling point than water so better suited to high and low temp. variations due weather extremes.
• Because of toxicity when ingested there is a move to switch to less toxic propylene glycol – which many countries in Europe have already done
Applied ConceptsApplied Concepts
• Distillation – separation of various fractions in a mixture by individual boiling points
• Reactors – designed to break or make chemical bonds which changes reactants into products
Applied ConceptsApplied Concepts
• Catalytic Cracking – splits side stream of fractionating column into smaller, more useful molecules – for example, kerosene into hexane and hexene
• Hydrocracking – process used to boost gasoline yield
• Alkylation – uses a reactor to make one large molecule out of smaller ones. For example isobutane and olefins into high octane alkylates
Review
• List importance of applied chemistry to process technicians
• Re-write all vocabulary words and their definitions
• Understand difference between the following:– Organic and inorganic– Endothermic and exothermic– Acids and bases
• Define the 4 basic chemical reactions most common to process industry
Work
• Read CAPT Chapter 11 (pages 158 – 169)– Do questions 1 – 13 on pages 170 & 171)
• Read Thomas Chapter 13 (pages 281 – 302– Do questions 1 – 21 on page 303
• Module 5, Exercise 1 – Chemistry Supplement
• Major Grade• In class example worked by group