History and economics of cellulosic ethanol

Thomas Jeffries

Specialized Library AssociationChicago, Illinois

July 17, 2012

If we are to survive as a society we must find a way to convert

our fossil energy capital into the means for renewable energy

income.

R. Buckminster Fuller

Biofuels have been under development for 200 years

Ethanol production from wood is much older than many think.The chemistry has not changed.Biotechnology has provided new impetus.Emphasis increased during wars and times of fuel shortage.

Earliest attempts - 1819

Henri Braconnot (1819) treated wood with cold 91.5% sulfuric acid, and fermented the sugar

French chemist elected member of the Paris Académie des Sciences in 1823 Braconnot, H. 1819. Gilbert's

Annalen der Physik, 63:348-371

Commercialization in Europe - 1855

Arnould (1854) used 110 parts of concentrated sulfuric acid per 100 parts of wood and obtained 80 to 90% of wood in solution

Melsens (1855) used 3 to 5% sulfuric acid under pressure at 180°C

Pelouze (1855) erected a factory for the recovery of ethanol from wood in Paris

Von Demuth, R. 1913. Zeitschr. F. angew Chemie Aufsatzteil 1913, 26:786-792

The Simonsen process (1894-1898)

First comprehensive examination of engineering parametersUsed dilute acid under high pressure 15 minute hydrolysis, 0.5% sulfuric acid, 9 atm steam (≈180°C). Yielded 26.5% sugar on a dry wood basisProduced 7.6 L ethanol/100 kg wood

Kressmann studied dilute acid hydrolysis at FPL from 1910 to 1922

Need for ethanol in synthetic rubber synthesisExcess wood residues accumulated at sawmills ($0.50 per ton)Raw material cost was ≈ 2 cents per gallon of ethanol.Sugars from softwoods were about 70 percent fermentable while those from hardwoods were 30 percent fermentable by yeast.

First US commercialization in 1910 by the Standard Alcohol Company

Built a cellulosic ethanol plant in Georgetown, South Carolina to process waste wood from a lumber mill Later built a second plant in Fullteron, LouisianaEach produced 5,000 to 7,000 gal ethanol per day from wood wasteBoth were in production for several years

Robert Rapier Sep 10, 2009Sherrad EC & Kressman FW (1945) Review of Processes in the United States Prior to World War II. Industrial and Engineering Chemistry 37(1):5-8

Problems with pentoses and sugar degradation

Foth noted in 1913 that the unfermentable sugars in hydrolysates mainly come from pentosansThe pentosans are completely converted to pentoses in the first cookGlucose was degraded by acid at high temperatures

Foth, G. 1913. The recovery of alcohol from wood. Chemiker Zeitung 37(120), p. 1221

From 1916 to 1922, FPL took acid hydrolysis to the pilot scale

Settling tank, Single effect evaporator,

Hydroextractor

Hydrolyzer

Evaporator, Condenser

These findings led to the percolation process

Hemicellulosic sugars (xylose , arabinose) are hydrolyzed rapidly – but then break down in the acidCellulosic sugars (glucose) are hydrolyzed more slowly and are more stableUse a percolation process with rising acidity and temperature to extract

Madison Wood Sugar process - 1943

Developed in response to need for ethanol for the synthesis of synthetic rubber.

Based on the Scholler process in which dilute acid is percolated over a bed of wood chips.

Differs in that dilute acid is percolated initially at a lower temperature then at progressively higher temperatures until only lignin remains.

Sugars are collected in a series of tanks, neutralized with CaO and fermented.

Development of the Scholler process

Following World War II, scientists modified the German Sholler process for use in the United StatesJ.A. Hall directed pilot plant studies at the Dow Chemical Company plant in Marquette, Michigan and Vulcan Copper and Supply Co. at Cincinnati Ohio.Designed a pilot plant to produce 11,500 gal of ethanol/day (4 million gallons/year)

Based on Douglas fir (lowest xylan)0.4 to 0.85% sulfuric acid6 hour hydrolysis; 8:1 L:S ratio50 to 150 psig; 298-366°FYield of 52 gallons per ton (2% beer)

Vulcan Wood to ethanol plant, Springfield Oregon, 1945Designed by Ray Katzen Operated by Jerry Saeman“The plant did run and made ethanol but had lots of problems.”… “Low concentration of sugar; lots of organic matter ran down the river; no alternative to that…”

Jerome Saeman, May 1, 2003

Tars, calcium sulfate made a hard scale and lining in pumps and valves requiring cleaning and maintenance

Ray Katzen, May 6, 2003

Constructed in 1944 operated until 1946: met target of 15,000 gal/day, 50 gal per ton

Wood to ethanol plant, Springfield Oregon, 1945

Arial view

Interior

History doesn’t repeat itself…

“To render automotive transportation independent of fuel imports and to produce domestically this fuel in the desired quantities, are the questions to be faced from the national point of view” -- Meunier 1922

1 bushel of corn yielded 2.4 gal EtOH in 1922Cost about $0.27/gal prior to WWI

Today one bushel of corn yields 2.75 gal EtOHCosts about

But it rhymes…

One ton of sawdust yielded about 12 to 20 gal EtOH/ton in 1922

“If the manufacturing cost of producing ethyl alcohol from wood can be reduced to the same figure or nearly the same figure as that for making it from grain or molasses, there will be a large margin in favor of producing the alcohol from wood waste.” -- F.W. Kressman, USDA Bulletin No. 983, 1922, p. 2.

Today, one ton of sawdust could yield ≈70-90 gal of ethanol

The maximum theoretical yield is 110-140 gal

We have made much progress with cellulosics

Two paths to cellulose saccharificationJerry Saeman 80th birthday1996

Elwin Reese at age 62 1973

Enzymatic saccharification of celluloseReese, Siu and Levinson - 1950

Cellulase is not a single enzyme but a complexC1, Cx hypothesis (later replaced with endo/exo)

Reese organized and chaired an ACS symposium in Washington, DC on cellulase in 1962Katz and Reese produced 30% glucose from 50% cellulose in 1968Second ACS symposium on cellulase in Atlantic City 1969Natick symposium on “Enzymatic Conversion of cellulose 1975

Early contributors to cellulose enzymatic saccharificationKendall King

Virginia Polytechnic

Geoffery HalliwellRowett Res. Institute

Kazutosi NisizawaTokyo University

Karl Erick ErickssonSwedish Forest Products Laboratory

Keith SelbyShirley Institute

Ellis CowlingYale School of Forestry

Nobuo ToyamaMiyazaki University

Tarun K. GhoseIndian Institute, New Delhi

Mary MandelsNatick Lab

Development of Trichoderma reesei

QM6a first isolated from deteriorated shelter from Bougaineville Island at the end of WW2Originally identified as T. viride; in 1977 recognized as T. longibrachiatum named T. reesei by Simmons in 1977Produces a complete extracellular cellulase complexScheduled for complete genome sequencing by DOE in 2003

QM6A

QM9123 1969

QM9414 1971

TK041 1977

MCG77 1977

Linear accelerator

Linear accelerator

UV -Kabicidin

UV

M7

NG14

C-30

MCG80

1976

1977

1978

1980

UV

nitrosoguanidine

UV

UV -Kabicidin

Development of hyper secreting strains

Bland Montenecourt and Doug Eveleigh developed RutC30Looking for carbon catabolite resistance - discovered hyper-secreting strainUsed oxgall extract and phosphon D as colony restriction agentsBlocked phospholipid production

Discovery of pentose fermenting yeasts

Wang and Schneider - NRC, Canada

Fermentation of D-xylulose (1980)Clete Kurtzman - USDA, NRRL

Fermentation by P. tannophilus (1981)C.S. Gong - Purdue University

Candida sp. Mutant (1981)Tom Jeffries - FPL

Aerobic conversion by C. tropicalis (1981)

The virtual community -1981-1982

First international computer conference on biotechnology for fuels and chemicals; Organized through IEA

One of the very first computer conferences.

Initiated by Swedish innovator; coordinated by John Black, University of Western Ontario

Brought together researchers from around the world to exchange information on bioconversion for renewable fuels and chemicals

Sweden, Canada, Japan, United States, Soviet Union, India, France, Mexico, Brazil (et al.)

Metabolic engineering - 1984

Lonnie IngramMetabolic engineering of Escherichia coliPET operon -- from Zymomonas mobilis

Min Zhang, Steve PicataggioMetabolic engineering of Z. mobilis Pentose metabolic genes from E. coli

Accelerating forces

Enzymes from uncultured organismsIn-vitro recombinationDirected evolutionPathway optimizationGenome-wide expression analysisMetabolic modelingPetroleum prices

Source: U.S. Energy Information Administration Annual Energy Review, Table 5.21.¹ Composite of domestic and imported crude oil.² In chained (2005) dollars, calculated by using gross domestic product implicit price deflators. See "Chained Dollars" in Glossary.

19681970

19721974

19761978

19801982

19841986

19881990

19921994

19961998

20002002

20042006

20082010

0

10

20

30

40

50

60

70

80

90

100

U.S. Refiner Acquisition Cost¹ of Crude Oil, 1968-2010

Nominal Real²

Dollars

per

Barr

el

Average in 2011 - $111

Arab-IsraeliConflict 1973

Iranian hostageCrisis 11/79-1/81

Peak oil 2005?

Collapse of oilcartel 1980-86

US Production has passed its peak

Ethanol production has tracked with petroleum price

1984 1990 1996 2002 2008 20140

2000400060008000

10000120001400016000

Grain ethanol (10^9) gal

11/14/84 1/31/93 4/19/01 7/6/090

20

40

60

80

100

120

140

U.S. Crude Oil ($/bbl)

Global warmingWhat are the drivers?

The greenhouse effect has been recognized for 185 years

Joseph Fourier discovered greenhouse effect in 1827John Tyndall discovered in 1861 that H2O and CO2 were largely responsible

Svante Arrhenius showed the role of CO2 in 1896 and he and Chamberlin recognized the feedback effect with water by 1905

Projected surface temperature of the globe in 150 years

Nine of the world's 10 warmest years since records began were in the 1990s, including.Temperatures in the 1990s were 0.33 C higher than in 1961-90 and 0.7 C higher than those at the turn of the century

We are already seeing the effects of global change

Each decadeSpring comes 5 days earlier Animal and plant ranges move 6 km further north

Ice thinning in arctic and alpine glaciersVegetation changes in arctic

Temperature correlates closely with CO2 levels395 ppm

Regional emissions

commitment from existing energy

and transportation infrastructure

Regional emissions

normalized by regional population

Regional emissions

normalized by regional GDP

Future CO2 Emissions and Climate Change from Existing Energy Infrastructure Steven J. Davis, et al. Science 329, 1330 (2010)

Global emissions of CO2 have an intergenerational effect

The last and the current generation contributed approximately two thirds of the present day CO2-induced warming.

Global mean temperatures would increase by several tenths of a degree for at least the next 20 years even if CO2 emissions were immediately cut to zero.

Friedlingstein and Solomon, 2005 PNAS 102(31):10832–10836

Solid line shows contribution to CO2 by each “generation” continuing at same rateDotted line shows contribution if CO2 emissions were immediately stopped

CO2 is rising at a faster rate than seen in 400,000 years

Domestication Of first plants

Biofuels can reduce CO2 production

Ethanol, methane and biodiesel are the most immediate bioenergy sourcesEthanol and biodiesel recovered in processingMethane recovered from feedlot operationsGreatly reduces CO2 emissions

Summary of energy efficienciesFuel Energy yield

Net Energy (loss) or gain

Gasoline 0.805 (19.5 %)

Diesel 0.843 (15.7 %)

Ethanol 1.34 34 %

Biodiesel 3.20 220 %

Source: Minnesota Department of Agriculture

Biofuels account for ≈7% of the US automotive and light truck fuel supply

>14 billion gallons of ethanol/yrVirtually all derived from grainEthanol can be blended at up to 10% by vol.Has only 2/3 the energy content of gasoline

Production of ethanol from corn is reaching unsustainable levels

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

20

06

20

07

20

08

20

09

20

10

0

3,000

6,000

9,000

12,000

15,000

U.S. Production, Consumption, and Trade* of Fuel Ethanol

Production Net Imports Consumption

Mill

ion

Ga

llon

s E

tha

no

l

1986

1989

1992

1995

1998

2001

2004

2007

2010

0

3,000

6,000

9,000

12,000

15,000

-

9

18

27

36

45

U.S. Corn Production and Use for Fuel Ethanol

Production Used for Ethanol PercentYear

Mill

ion

Bu

sh

els

Co

rn

Pe

rce

nt

co

rn u

se

d f

or

eth

an

ol

CTL = coal to liquids; GE = grain ethanol; CE = cellulosic ethanol; BTL = biomass to liquids; Gas = gasoline

Cellulose to ethanol reduces CO2 emissions

Isobutanol could provide 12% of US automotive and light truck fuels

> 14 billion gallons of ethanol annuallyVirtually all derived from grain (corn)Ethanol can be blended at up to 10% by vol.

Has only 2/3 the energy content of gasoline

Equivalent to 7%

Isobutanol can be blended at 16% by vol

Has ¾ the energy content of gasoline

Production from cellulosics is essential for market expansionDomestic biomass resource is sufficient

Wheat straw and forest residues are potentially the most economical feedstocks

Feedstock WTA WTPPrice gap

($/dry ton)Price gap

($/gal)Corn stover 92 25 67 0.96Alfalfa 118 26 92 1.31Switchgrass 117 26 90 1.29Miscanthus 110 27 84 1.20Wheat straw 75 27 49 0.70SR woody crops 89 24 65 0.93Forest Residues 78 24 54 0.77

Source: National Research Council, 2011 Renewable Fuel Standard (prepublication)

WTA = willing to accept; WTP willing to pay

Implicit subsidy required for cellulosic ethanol at $111/bbl oil

The US produces large amounts of biomass annually

Basic advances are needed in cellulase saccharification and biocatalyst researchMore funding for basic energy research is desperately needed“Competitive funding for basic research in plant biology by all federal agencies totals only about 1% of the National Institutes of Health’s budget”

Chris Somerville Science 312:1277 (2 JUNE 2006)

Barriers to commercialization

Cellulose is recalcitrant and requires large amounts of enzymes to produce sugarLignin occludes polysaccharides and inhibits enzymatic hydrolysis of carbohydratesEnergetically expensive and corrosive chemical pretreatments are required. Yeast currently used in large-scale ethanol production cannot efficiently ferment sugars other than glucose.

Why are we doing this work?

Ethanol fuels can help alleviate global warming

Wood and agricultural residues are available

Metabolic engineering can increase ethanol production