Welcome Back!. Topics for Today Gasoline additives (MTBE, ethanol, and oxygenates) Part II!

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Welcome Back! Slide 2 Topics for Today Gasoline additives (MTBE, ethanol, and oxygenates) Part II! Slide 3 Readings for Today 4.10 Newer fuels and other sources Slide 4 Topics for Today The other part of crude oil Uses of polyethylene Slide 5 Readings for Today 9.1 Polymers: The long, long chain 9.2 The Big Six 9.3 Addition polymerization 9.4 Polyethylene Slide 6 Topics for Wednesday Where Do We Find Other Addition Polymers? PETE (A Polyester)! Slide 7 Readings for Today 9.2 The Big Six 9.3 Addition polymerization 9.5 Condensation Polymers Slide 8 Topics for Today Gasoline additives (MTBE, ethanol, and oxygenates) Part II! Slide 9 Whats good about using ethanol? 1) Reduced CO emissions * 2) Less direct impact if spilled Slide 10 Problems with ethanol? Slide 11 Slide 12 Air Pollution Implications CO (tons / day) NO x (tons / day) VOCs (tons / day) Emissions compared to today -237.5+ 10+ 25 - means decreased emission + means increased emission Slide 13 Problems with ethanol? 1) Air pollution compromise Slide 14 Problems with ethanol? 1) Air pollution compromise 2) We eat corn! Slide 15 What is ethanol currently made from? Slide 16 Reducing supply of sweet corn! Increased prices of corn Over the past year, corn prices have doubled! Slide 17 Problems with ethanol? 1) Air pollution compromise 3) Energy requirement 2) We eat corn! Slide 18 For gasoline, we use 6 gallons. Compared to the energy we get out of the fuel We would have to use 75 gallons of ethanol to make 100 gallons Slide 19 For equal volumes of ethanol and gasoline Which contains more energy? This leads to reduced gas mileage Slide 20 Problems with ethanol? 1) Air pollution compromise 3) Energy requirement 4) More corrosive than gasoline 2) We eat corn! Slide 21 Cannot use the same pipelines used to transport gasoline Slide 22 Why do we use fuel additives? 1) To increase the octane number 2) To make a cleaner fuel Slide 23 Oxygenate #2 CH 3 | CH 3 O C CH 3 | CH 3 An ether MTBE Slide 24 Alcohol R O H Ether R O R R = some hydrocarbon group (methyl, ethyl, etc) Slide 25 Oxygenate #2 CH 3 | CH 3 O C CH 3 | CH 3 An ether MTBE Octane rating = 116 Slide 26 Oxygenate #2 CH 3 | CH 3 O C CH 3 | CH 3 An ether MTBE Slide 27 Oxygenates M = methyl T = tert or tertiary B = butyl E = ether CH 3 | CH 3 O C CH 3 | CH 3 KNOW Slide 28 Review: Where have we seen an ether before? CH 3 O CH 3 Dimethyl ether Slide 29 CH 3 O CH 2 CH 3 Name? ethyl methyl ether Isomers? Slide 30 Why can MTBE be added at the refinery? Slide 31 CH 3 | CH 3 O C CH 3 | CH 3 H H | | H C C OH | | H H Which is more polar? Which will better dissolve in gasoline? Slide 32 MTBE Replaced TEL in 1979 ~11% by volume Not used much anymore Why not? Slide 33 Leaks into the ground water Health effects uncertain Distinct odor at very low levels How does it leak into the groundwater? Slide 34 Underground Storage Tanks Slide 35 Slide 36 Prior to MTBE Remove leaking tank, Spill some gasoline. (insoluble in groundwater) Gasoline degrades quickly. Slide 37 After MTBE Remove leaking tank, Spill some gasoline. (insoluble in groundwater) Gasoline degrades quickly. But MTBE persists in the water. Slide 38 So far, we have only been focusing on making fuel from crude oil Slide 39 Slide 40 What else can we do with crude oil? Slide 41 Slide 42 A closer look Slide 43 Slide 44 Slide 45 Where do we find plastics? Slide 46 Everywhere! ! Slide 47 Just the beginning! Assignment #4 due Wed the 18 th ! Slide 48 Chemically speaking, what are plastics? Slide 49 Polymers!! Really, really big molecules made up of smaller ones Slide 50 Polymers!! The smaller molecules are called monomers. Slide 51 Where have we seen a polymer in Chem 108? Slide 52 Cellulose A chain (polymer) of glucose molecules. Glucose: C 6 H 12 O 6 Slide 53 Cellulose The monomer is glucose! Other natural polymers? Slide 54 Spider Webs and Silk Slide 55 Other natural polymers? Wool Slide 56 Other natural polymers? Fur and Hair Slide 57 Beaks Feathers Claws Fingernails Other natural polymers? Slide 58 Proteins! Other natural polymers? Starch! Slide 59 Some synthetic (manmade) polymers? Slide 60 Teflon Kevlar Nylon Gore-Tex Polyester Rayon And many, many more! Other synthetic polymers Slide 61 Polyethylene Polypropylene Polyvinyl Chloride Polystyrene Other synthetic polymers Slide 62 Fig.09.01a Table 9.1 (p. 401) Slide 63 Fig.09.01b Table 9.1 (p. 401) Slide 64 Polyethylene Table 9.1 (p. 401) Slide 65 How do we make PE? Slide 66 Polyethylene Ethylene = double bond Whered the double bond go? Slide 67 Monomer for PE CC HH H H Name? Ethene (or ethylene) C 2 H 4 How do we get PE from ethene? Slide 68 Free Radical Polymerization! 1. Initiation Reaction CC H H H H R.R. + Slide 69 CC H H H H R.R. +.. CC.C. HH HH R Free Radical EthyleneNew Radical Slide 70 Free Radical Polymerization! 1. Initiation Reaction CC H H H H R.R. +.. CC.C. HH HH R Free Radical EthyleneNew Radical What happens to a nearby ethylene molecule? Slide 71 CC.C. HH HH.. R New Radical CC H H H H +.. Ethylene CC HH HH.. R C HH HH C.C. Newer Radical Then what happens? Slide 72 Figure 9.5, page 407 Slide 73 Polyethylene This will go on for 1000s of units How else can we write this? Slide 74 Polyethylene Repeating Unit Slide 75 Polyethylene CC HH HH n Easier way to write PE! n can be in the 1000s and higher OR CH 2 n Slide 76 Polyethylene formation [ ]n]n CH 2 CH 2 n C = C H HH H RR Slide 77 Addition Polymerization!! Initiated by a free radical. No by-products! http://chemincontext.eppg.com/chapter9/cic_interface9.swf Animation ! Slide 78 PE comes in more than 1 form! Slide 79 Types of Polyethylene Figure 9.7 (p. 409) Slide 80 Why does HDPE have a slightly higher density? Different chemical structures = different chemical properties Linear ~0.96 g / mL Branched ~0.93 g / mL