Citrus-Based Biorefinery - Opportunities and Challenges - Patrick L. Mills Dept of Chemical &...
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Transcript of Citrus-Based Biorefinery - Opportunities and Challenges - Patrick L. Mills Dept of Chemical &...
Citrus-Based BiorefineryCitrus-Based Biorefinery- Opportunities and Challenges -- Opportunities and Challenges -
Patrick L. MillsPatrick L. Mills Dept of Chemical & Natural Gas Engineering Dept of Chemical & Natural Gas Engineering
Texas A&M University-KingsvilleTexas A&M University-Kingsville Kingsville, TX 78363 Kingsville, TX 78363
[email protected]@tamuk.edu
OH
CREL Annual Meeting – Washington University in St. LouisCREL Annual Meeting – Washington University in St. LouisEnergy: From Molecular Transformations to SystemsEnergy: From Molecular Transformations to Systems
October 25, 2006October 25, 2006
www.praj.netwww.ars.usda.gov
GRADUATED
FI RST, WE’LL REDUCEOUR DEPARTMENTEXPENSES BY LOWER-I NG OUR GRADUATI ON
REQUI REMENTS
THEN WE’LL REWRI TEOUR DEPARTMENTMI SSI ON STATEMENTTO MAKE I T FI T BETTER
GRADUATED
FI RST, WE’LL REDUCEOUR DEPARTMENTEXPENSES BY LOWER-I NG OUR GRADUATI ON
REQUI REMENTS
THEN WE’LL REWRI TEOUR DEPARTMENTMI SSI ON STATEMENTTO MAKE I T FI T BETTER
GRADUATED
FI RST, WE’LL REDUCEOUR DEPARTMENTEXPENSES BY LOWER-I NG OUR GRADUATI ON
REQUI REMENTS
THEN WE’LL REWRI TEOUR DEPARTMENTMI SSI ON STATEMENTTO MAKE I T FI T BETTER
GRADUATED
FI RST, WE’LL REDUCEOUR DEPARTMENTEXPENSES BY LOWER-I NG OUR GRADUATI ON
REQUI REMENTS
THEN WE’LL REWRI TEOUR DEPARTMENTMI SSI ON STATEMENTTO MAKE I T FI T BETTER
GRADUATED
FI RST, WE’LL REDUCEOUR DEPARTMENTEXPENSES BY LOWER-I NG OUR GRADUATI ON
REQUI REMENTS
THEN WE’LL REWRI TEOUR DEPARTMENTMI SSI ON STATEMENTTO MAKE I T FI T BETTER
GRADUATED
FI RST, WE’LL REDUCEOUR DEPARTMENTEXPENSES BY LOWER-I NG OUR GRADUATI ON
REQUI REMENTS
THEN WE’LL REWRI TEOUR DEPARTMENTMI SSI ON STATEMENTTO MAKE I T FI T BETTER
The New Departmental PlanThe New Departmental Plan
Starting ReferencesStarting References
2. R. J. Braddock, Handbook of Citrus By-Products & Processing Technology,Wiley-Interscience: New York, ISBN 0471190241, 247 pp, 1999.
4. Dan A. Kimball, Citrus Processing: A Complete Guide, 2nd Edition,Chapman & Hall Food Science Series, Aspen Publishers, Gaithersburg, MDISBN 0834212587, 450 pp, 1999.
5. T. R. Graumlich, “Potential fermentation products from citrus processingwastes,” Food Technology, 94-97, Dec 1983.
6. W. Q. Hull, C. W. Lindsay, & W. E. Baier, “Chemicals from oranges,”Ind. Engng. Chem., Vol. 45, No. 5, 876-890, May 1953.
3. R. J. Braddock, “Importance of by-products to citrus juice processing,”Fruit Processing, 5, pp 310-313 (2004).
1. B. Kamm, P. R. Gruber, & M. Kamm (editors), Biorefineries – IndustrialProcesses & Products: Status Quo & Future Directions,John Wiley: New York, ISBN 3527310274, 964 pp, April 2006.
Morphology of Citrus FruitMorphology of Citrus Fruit
zest
Pericarpor rind
Orange Citrussegment
wall
Mesocarp orpulp
www.infovisual.info
• 40 to 65 wt % juice• 35 to 60 wt % waste
• Lipids - oleic, linoleic, linolenic, palmitic, stearic acids; glycerol & physterol
• Sugars - glucose, fructose, sucrose, galactose, xylose, rabinose, ….)
• Acids - citric, malic, tartaric, benzoic, oxalic, succinic
• Insoluble carbohydrates – cellulose, pectin
• Flavonoids, peel oil, pigments, vitamins, minerals, …
Nutrient Composition of Citrus By-ProductsNutrient Composition of Citrus By-Products
Total World Annual Citrus Production*Total World Annual Citrus Production*
70 to 105 million tons/yr 70 to 105 million tons/yr 2000–2003 (avg’d) 2000–2003 (avg’d)
*USDA/FAS, 2003 Horticultural & Tropical Products Div.,Wash.,DC
Sweet Orange
68%
Minor genuses
3%
Tangerine18%
Lemon6%
Grapefruit5%
- Sour orange- Shaddock- Citron- Lime
USA21%
Brazil24%Med
24%
ROW31%
C. Reticulata
C. Sinensis
C. LimonC. Paradisi
C. QuanantiumC. GrandisC. MedicaC. Aurantifolia
Example: Florida Citrus Production*Example: Florida Citrus Production*
*USDOE, Office of Energy Efficiency & Renewable Energy
MM = 1 x 106
Property AmountCitrus Trees, MM 103Acreage 800,000USA Production 80%Citrus Boxes, MM 287On-Tree Value $1 MMMTotal Industry Value $ 9 MMMWet Waste, MM tons 5Dry Waste, MM tons 1.25EtOH Potential, MM gals 120
Added ValueFrom JuiceBy-Products
90 lbs/box
Citrus Juice Process & Material BalanceCitrus Juice Process & Material BalanceFresh Citrus Fruit
3000 b/hr 123,000 kg/hr
Juice extractors
Wet Peel54,600 kg/hr 82% H2O
Dryer Feed25,600 kg/hr 61% H2O
Press Cake19,000 kg/hr 65% H2O
Hammermill
Reaction Time
Presses
Dryer 14,500 kg/hr
Press Liquid35,600 kg/hr 9o Brix
Citrus Juice
Waste Heat Evap30,000 kg/hr
Oil Mill / Plant Waste
Molasses6400 kg/hr 9o Brix
33.4 %
Pellets11,000 kg/h 10% H2O
d-Limonene140 kg/hr
Molasses4400 kg/hr 72o Brix
66.6 %
(Soluble Fraction)(Soluble Fraction)
(Insoluble Fraction)(Insoluble Fraction)
Process Flow for Citrus By-ProductsProcess Flow for Citrus By-Products
Fresh Citrus Fruit Residue(Ground or Chopped)
Citrus SeedsDried Citrus Pulp
with Liquor
Press LiquorPressed Fresh
Pulp
Citrus Molasses
Citrus SeedMeal
Citrus OilsDried Citrus Pulp(w/o Molasses)
Dried CitrusMeal
Pressure withAdded Ca(OH)2
Sold as Molasses
Dried Citrus Pulp(with Molasses)
Pelleted & AddedBack to Pulp
Pressure Sieved
Dehydration Dehydration
Dehydrated without pressing
Ca(OH)2 added
Addition
Bampidis & Robinson, Animal Feed Sci. Tech. 128 (2006)
Distribution of Citrus By-ProductsDistribution of Citrus By-Products
9.80
4.90
3.43 3.19
0.74 0.74 0.49
0
2
4
6
8
10
Wt % ofBy-Product
(Orange Basis)
Basis: Basis: OrangesOranges = 40.8 kg/box; = 40.8 kg/box; Juice Yield Juice Yield ca.ca. 55%55%
Distribution of Orange Juice By-ProductsDistribution of Orange Juice By-Products
Basis: 2005 – 2006 USA Production of 695,275 MTBasis: 2005 – 2006 USA Production of 695,275 MT
Source: www.fas.usda.gov
Flavonoids2%
Pulpwash soluble solids
3%
Pectin (150 grade)
14%
Molasses (72 °Brix)15%
Peel dry pellets (10% H2O)
42%
Essential oil and d-limonene
3%
Frozen pulp21%
Pectin & Pectic AcidPectin & Pectic Acid
Pectic Acid (D-Polygalacturonic acid)
Pectin Molecule
Recovery of Pectin from Citrus PeelRecovery of Pectin from Citrus Peel
• Pectin (a polysaccharide) - white, spongy inner part of the peelPectin (a polysaccharide) - white, spongy inner part of the peel
• Significant yield loss & waste generation with conventional hydrolysis Significant yield loss & waste generation with conventional hydrolysis
BackgroundBackground
OpportunityOpportunity• Significant growth in use of low-methodoxylSignificant growth in use of low-methodoxyl (LM) pectin as a pectin as a
- Thickening or gelling agent- Thickening or gelling agent
- In formulated food applications (yogurt, milk, desserts, etc...)- In formulated food applications (yogurt, milk, desserts, etc...)
• Method for extraction & conversion of high-methodoxyl (HM) pectinMethod for extraction & conversion of high-methodoxyl (HM) pectinfrom citrus peels with high efficeincyfrom citrus peels with high efficeincy
• New enzyme or catalysts for rapid conversion of HM to LM pectinNew enzyme or catalysts for rapid conversion of HM to LM pectin
• Efficient methods for purification and formulationEfficient methods for purification and formulation
NeedsNeeds
Citrus Peel Waste as a Bio FeedstockCitrus Peel Waste as a Bio Feedstock
• Represents ca. 40 to 50 % of citrus fruitRepresents ca. 40 to 50 % of citrus fruit
• Dried pellets used as cattle feed supplementDried pellets used as cattle feed supplement
• Second to corn as a source of feed nutrientsSecond to corn as a source of feed nutrients
• CaO added - neutralize & de-esterify pectinCaO added - neutralize & de-esterify pectin
• Diffusion controlled process w/molassesDiffusion controlled process w/molasses
• COM can exceed cattle feed selling priceCOM can exceed cattle feed selling price
• Contains Contains solublesoluble & & insolubleinsoluble carbohydrates carbohydrates ((glucose, fructose, sucroseglucose, fructose, sucrose, , pectin, cellulose,pectin, cellulose, hemicelluloseshemicelluloses w/ galacturonic acid, glucose, w/ galacturonic acid, glucose, arabinose, xylose, … as monomeric units)arabinose, xylose, … as monomeric units)
Composition of Citrus JuiceComposition of Citrus JuiceProcessing Wastes (Wet Processing Wastes (Wet vsvs Dry Material) Dry Material)
0
10
20
30
40
50
60
70
80
90
Water TotalSolids
Solublesugar
AlcoholInsoluble
Solids(AIS)
CrudeFiber
Pectin CrudeProtein
Fat (Ether
extract)
Ash
Wt%
Composition at Minimum Water (W%)
Composition at Maximum Water (W%)
Dry Material
• Higher polysaccharide concentration
• Greater potential yield of sugars
• Higher energy consumption vs wet
• Higher pectin vs wet material0
10
20
30
40
50
60
70
80
90
Solublesugar
AlcoholInsoluble
Solids(AIS)
CrudeFiber
Pectin CrudeProtein
Fat (Etherextract)
Ash
Wt%
Composition at minimum AIS%
Composition at maximum AIS%
Wet Material
• Lower sugar content vs dry material
• Lower yield of sugars
• Lower energy consumption
• Hydrolysis of polysaccharides req’d
Composition of Alcohol Insoluble SolidsComposition of Alcohol Insoluble Solids (Cell Wall Fraction of Orange Peel)*(Cell Wall Fraction of Orange Peel)*
0
5
10
15
20
25
30
Wt %
Not Useful forEtOH Production
Grohmann & Bothast, ACS Symp Ser. 566 (1994)
Raw Materials forEtOH Production
• Fructose & glucose present in nearly equimolar amountsFructose & glucose present in nearly equimolar amounts• No starch is present, unlike other Ag residsNo starch is present, unlike other Ag resids• Some organic acids, Some organic acids, e.ge.g., galacturonic acid., galacturonic acid
D-Galacturonic Acid D-Galacturonic Acid StructureStructure
- Formed by the hydrolysis of - Formed by the hydrolysis of
pectinpectin
- Can be converted to d-glucose- Can be converted to d-glucose
Conversion of Orange Total Peel Solidsto Monomeric Sugars
- Comparison of Various Treatments-
Conversion of total peel solids to monomeric sugars by enzymatic and combined acid and enzymatic treatments. Left bar (Unt) of each pair represents a mean of results obtained by enzymatic treatment alone, without acid treatment. The right bar (Tr) of each pair represents the mean of results obtained by sequential acid and enzymatic treatment. The symbols above each pair of bars represent the enzymes (or combination of enzymes) used in the enzymatic part of the treatment (C=cellulase; P=pectinase; -glucosidase). The last pair of bars, labeled I"PCG, represents results of a treatment with a mixture of pectinase, cellulase and ~-glucosidase in excess. The individual sugars released are marked on the right side of the graph (Ara=arabinose; Fru=fructose; Gal=galactose; Glc=glucose; G.A=galacturonic acid; Xyl=xylose). Grohmann, K.; Cameron, R.G;. Buslig, B.S Bioresource Technology 54 (1995) 129-141
C CG P PC PCG PCG
Su
cro
se
Glu
cos
eF
ruc
tos
eG
alac
tose
Ara
bin
ose
Xyl
ose
Rh
am
ose
Gal
act.
aci
dT
ota
l S
ug
ars
Inso
l. R
esid
.U
nk
no
wn
Aqueous Extract
Insol. Solids (Acid Hydrolyzed)
Insol. Solids (Enzy. Hydrolyzed)
Enzy. Hydrolysate of Peel
0
20
40
60
80
wt %
Products from Various Solubilization MethodsProducts from Various Solubilization Methods
Enzymatic Hydrolysis of Orange Enzymatic Hydrolysis of Orange PeelPeel
Conversion of total peel solids to reducing sugars during enzymatic hydrolysis of untreated orange peel ( ...... ) and peel pretreated with 0-06% sulfuric acid at pH=2.0 at 100, 120 and 140°C for 10 min, respectively. Treatments: a No acid pretreatment;---<> . pH=2-0, 100°C, 10 min; ---o . . . . pH=2.0, 120°C, 10 min; - - - + . . . . pH=2.0, 140°C, 10 min.. Grohmann, K.; Cameron, R.G;. Buslig, B.S Bioresource Technology 54 (1995) 129-141
Enzymatic w/o acid pretreatment
Enzymatic w/diluteacid pretreatment
Effect of Particle Size onEffect of Particle Size onEnzymatic Hydrolysis of CelluloseEnzymatic Hydrolysis of Cellulose
Comparison of shake-flask and attrition methods for enzymatic hydrolysis of Whatman CF-11 cellulose. ( ) Unmilled control, () ball milled, () 60 g of glass beads, ( ) 136 g of stainless-steel beads, all with a shaker speed of 200 opm. () Attrition at 200 rpm. Cellulase complex PP 158: 1 IU/mL and 2% substrate. Neilson M. J., Kelsey, R. G ., and Shafizadhe F (1982). Biotechnology and Bioengineering, Vol. XXIV, pp. 293-304
w/o milling
conv. ball milling
Glass beads
SS beads
Attrition mill
Novel Hydrolysis Schemes of Citrus PeelNovel Hydrolysis Schemes of Citrus Peel
• Peel celluose & hemi-cellulose contain value-added glucose, sucrose,..Peel celluose & hemi-cellulose contain value-added glucose, sucrose,..
• Existing hydrolysis methods are slow (on the order of days)Existing hydrolysis methods are slow (on the order of days)
• Lack of basic understanding of hydrolysis kinetic-transport effects Lack of basic understanding of hydrolysis kinetic-transport effects
BackgroundBackground
OpportunityOpportunity
• Develop methods and process with significantly higher Develop methods and process with significantly higher conversion rates and selectivities to monomeric sugarsconversion rates and selectivities to monomeric sugars
• Novel enzymes, catalysts, and reactor systemsNovel enzymes, catalysts, and reactor systems
• Basic data on the reaction mechanism & kinetic-transport effects Basic data on the reaction mechanism & kinetic-transport effects
• Mathematical models for kinetics, transport, & reactor systems Mathematical models for kinetics, transport, & reactor systems
NeedsNeeds
Production of Orange Juice By-ProductsProduction of Orange Juice By-Products
Basis: 2005 – 2006 USA Production of 695,275 MTBasis: 2005 – 2006 USA Production of 695,275 MT
Source: www.fas.usda.gov
123.9
43.4
9.3 9.3
40.3
62.0
6.2
294.3
0
50
100
150
200
250
300
Dry pellets(10% H2O)
Molasses(72 °Brix)
Essentialoil and d-limonene
Pulpwashsolublesolids
Pectin (150grade)
Frozenpulp
Flavonoids Total
1 X
103 M
etr
ic T
on
s
Catalytic Oxidation of LimoneneCatalytic Oxidation of Limonene
trans-carveol
OAc
-terpinyl acetateR-Limonene
OH
+ O2
PdCl2 / CuCl2
HOAc
15 hr, pH = 6
or
R-Limonene
+ O2
PdCl2 / CuCl2
tert - BuOH
tert – BuOOH (aq.)
OOt-Bu
OOt-Bu
tert-butyl peroxide derivatives
+
w/o LiCl with LiCl
Oxdn of Limonene - Product DistributionOxdn of Limonene - Product Distribution
OAc OAc
1 2 3
O OH
4 5 6
OH
OAc
a. Conventional Wacker
OH OH O OH
OH
CHO
OOt-Bu
OOt-Bu
OOt-Bu
5 7 4 8 9
10 11 12 13 14
OH
b. Wacker with t-BuOH & t-BuOOH
Functionalized Derivatives of D-LimoneneFunctionalized Derivatives of D-Limonene
• Limonene & other mono-terpenes are recovered from citrus peel oilLimonene & other mono-terpenes are recovered from citrus peel oil• Derivatives (alcohols, aldehydes, ketones, allylic ethers, carboxylicDerivatives (alcohols, aldehydes, ketones, allylic ethers, carboxylic
acid esters, epoxides…) are useful in pharma, perfumery, flavors acid esters, epoxides…) are useful in pharma, perfumery, flavors
BackgroundBackground
OpportunityOpportunity
• Limited literature exists on application to natural products Limited literature exists on application to natural products
• Synthesis of new molecules, specialty polymers, & materialsSynthesis of new molecules, specialty polymers, & materials
• New organometallic catalysts for mono-terpene functionalizationNew organometallic catalysts for mono-terpene functionalization
• Fundamental studies on kinetics, mechanisms, multifunctional reactors Fundamental studies on kinetics, mechanisms, multifunctional reactors
• Novel multiphase microreactor system designs & mini-plants Novel multiphase microreactor system designs & mini-plants
NeedsNeeds
Example of a Flavonoid - DiosmetinExample of a Flavonoid - Diosmetin
• A human CYP1A enzyme activity-inhibiting natural flavonoid.A human CYP1A enzyme activity-inhibiting natural flavonoid. • Diosmetin has antimutagenic and anti-allergic behavior.Diosmetin has antimutagenic and anti-allergic behavior.
Flavones & FlavonoidsFlavones & Flavonoids• Naturally occurring aromatic secondary
plant metabolites
• > 4000 have been identified in plants
• Positive health benefits- antioxidants - cardioprotective- antiviral - anticarcinogenic- antiallergenic
• Amount & type depends on citrus genusand agricultural growth factors
Novel Sepn & Conversion Methods for By-ProductsNovel Sepn & Conversion Methods for By-Products
• By-products (lignin, protein, limonene..) are produced in variousBy-products (lignin, protein, limonene..) are produced in various
parts of the existing citrus process (hydrolysis, milling, etc.)parts of the existing citrus process (hydrolysis, milling, etc.)
• Some behave as enzyme inhibitors, microbiocides, contaminants,… Some behave as enzyme inhibitors, microbiocides, contaminants,…
BackgroundBackground
OpportunityOpportunity
• Develop rxn-sepn methods or processes that convert theseDevelop rxn-sepn methods or processes that convert theseto value-added products (flavors, perfumes, nutraceuticals,..)to value-added products (flavors, perfumes, nutraceuticals,..)
• New enzymes, catalysts, and/or reaction-sepn processes New enzymes, catalysts, and/or reaction-sepn processes
• Insight and new data on mechanisms & kinetic-transport effects Insight and new data on mechanisms & kinetic-transport effects
• Mathematical models for the kinetic-transport processesMathematical models for the kinetic-transport processes
NeedsNeeds
ConclusionsConclusions
• Citrus waste has potential as a biorefinery platform.Citrus waste has potential as a biorefinery platform.
• Notable differences vs corn & grain-based processes.Notable differences vs corn & grain-based processes.
• Conversion to EtOH represents one useful application.Conversion to EtOH represents one useful application.
• Specialty products would enhance economic potential.Specialty products would enhance economic potential.
• Various opportunities for novel enzymes, catalysts,Various opportunities for novel enzymes, catalysts,reactors, separations, & derivatives.reactors, separations, & derivatives.