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Narayan
September 17, 2010
Ramani Narayan
University Distinguished Professor
Biotechnology for preventing environmental
contamination (current and future trends and issues)
If you use any of the slide materials, please reference authorship and affiliation (Ramani Narayan, Michigan State University) – thank you
Copyright Ramani Narayan
Presentation at OECD Workshop on
Environmental Biotechnology, Rimini, Italy
Narayan
Biotechnology for preventing environmental
contamination (current and future trends and issues)
• Using bio renewable carbon feedstock to manufacture chemicals, plastics (& fuels)
• Reducing carbon footprint (Global warming/climate change issues)
• End-of-life
• Organics Recovery Strategy
• Biodegradability in industrial composting disposal systems
• Biodegradability in anaerobic digestors (for energy recovery)
• Environmental Safety
• Release into soil environment – soil biodegradability
• Waste water treatment system – anaerobic biodegradability
• Release into oceans – marine biodegradability
Narayan
Switching the “petro/fossil” CARBON to “bio-renewable”
Carbon reduces the carbon footprint:
• Reducing heat trapping CO2 emissions -- Minimizing global
warming/climate change problems
• Global warming potential (GWP – LCA terminology)
• Using (renewable) biomass feedstock as opposed to
petro/fossil feedstock – energy/environmental security
• Economic development – empowering rural farm, forestry and
allied manufacturing industry
Carbon footprint reduction strategy using bio content
Value Proposition for Biobased (Biomass/Renewable) Products (chemicals, & plastics)
3
Narayan
Carbon footprint reduction strategy using bio content Value Proposition for bio carbon vs petro/fossil carbon
4
CO2 + H2O (CH2O)X + O2photosynthesis
sunlight energy
Biomass, Ag & Forestry crops &
residues
NEW CARBON
Fossil Resources (Oil, Coal, Natural gas) -- OLD CARBON
> 106 YEARS USE – for materials,
chemicals and fuels
Rate and time scales of CO2 utilization is in balance using bio/renewable feedstocks
(1-10 years) as opposed to using fossil feedstocks
1-10 years
1-10 years
MATERIAL CARBON FOOTPRINT
Short (in balance) sustainable carbon cycle using bio renewable carbon feedstock
Ramani Narayan, Michigan State University
CARBON FOOTPRINT BASICS – Value Proposition
C
O
O CH2 CH2 OC
On
PET
Bio/renewable
feedstock
Crops & residues
(e.g. Corn, soybean
sugarcane)
Tree plantations
Lignocellulosics
Algal biomass
Oil, Coal,
Natural gas
H2C CH2
nPE
Naptha Ethylene
POLYETHYLENE
Ethylene oxide Ethylene
Glycol
POLYESTERS
MATERIAL CARBON FOOTPRINT PROCESS CARBON FOOTPRINT
EtOH
BIO monomers
Sugars, Oils
CH
CH3
C
O
O
PLAn
PLA, PHA’s
polyurethanes;
polyamides (Nylons);
polyesters
Ramani Narayan, Michigan State University
What is the impact of the material/product’s carbon footprint on the
environment ? –
100 Kg of polyethylene will result in net ?? Kg of CO2 released into
the atmosphere
Based on “petro carbon” vs “bio carbon”
100 Kg of polyester (PET )acid will results in net ?? Kg CO2 release
into the atmosphere
based on how many “petro carbons” vs “bio carbons”
Carbon footprint reduction strategy using bio content Material Carbon Footprint
6
C
O
O CH2 CH2 OC
On
PET
H2C CH2
nPE
Ramani Narayan, Michigan State University
314 kg of CO2 emissions reduction for every 100 kg of PE
resin in which the petro carbon is replaced with bio carbon
Material Carbon Footprint
0
50
100
150
200
250
300
350
PE/PP PET Bio-PE/PET/PLA
Kg of CO2 per 100 Kg resin
ZERO CARBON
FOOTPRINT
314 kg of CO2 emissions reduction for every 100 kg of PE
resin in which the petro carbon is replaced with bio carbon
Ramani Narayan, Michigan State University
PLASTICS LANDFILLED NO CO2 RELEASE -- SCENARIO
Material Carbon Footprint
Kg of CO2 per 100 kg of resin
-320
-270
-220
-170
-120
-70
-20
30
80
1 2
Zero footprint -- product
recycled, no release of
gas to the environment
PE/PP BIO-PE
Narayan
Carbon footprint reduction strategy using bio content
Measurement of bio (carbon) content – the Principle
9
C-14 signature forms the basis of
Standard test method to quantify
biobased content (ASTM D6866)
12CO2
Biomass/Bio-organics
Fossil Resources
(petroleum, natural gas, coal)
> 106 years
14CO2 – Solar radiation
(12CH2O)x (14CH2O)x
(12CH2)n (12CHO)x
NEW CARBON
OLD CARBON
Narayan, ACS (an American Chemical Society publication) Symposium Ser.939,
Chapter 18, pg 282, 2006
14N 14C 14CO2
Cosmic
radiation
12CO2
Narayan
Carbon footprint reduction strategy using bio content Measurement of biobased (carbon) content – ASTM D6866
10
C-product combusted to CO2
14C/12C ratio is compared directly with a oxalic acid radiocarbon
standard reference material (SRM 4990c) that is 100% new (bio)
carbon.
13.56 dpm/g is the absolute value of the primary oxalic acid standard
(SRM 4990b) corresponding to 100% biobased carbon content.
To correct for the post 1950 14C injection into the atmosphere, all
pMC values (after correction for isotopic fractionation) must be
multiplied by 0.93 to better reflect the true biobased carbon content
of the sample.
Contains concentration of 1.2 x 10-12 % of C-14 isotope equivalent to
100% bio carbon content
Narayan
Calculations -- Example
C
O
O CH2 CH2 OC
On
PET
1. Given the PET structure above, what would the percent biobased (renewable)
carbon content (EG component – O-CH2-CH2-O- is from biomass feedstock) [20%]
2. How much Kg of biomass carbon is present in 100 Kg of bio-PET (EG component –
O-CH2-CH2-O- is from biomass feedstock) [12.5 Kg]
3. How much CO2 reductions achieved by incorporating biomass derived EG in to
37.5 million metric tons of PET [17.19 million metric tons]
4. The above CO2 emissions reduction eliminates consuming how many million
barrels of oil each year [40 million barrels of oil]
5. If the above sample was subject to ASTM D6866 analysis, what biobased
(renewable) carbon content would be obtained [20% biboased content]
ASSIGNMENT PLANTBOTTLE
BIO
Narayan
Carbon footprint reduction strategy using bio content Terminology:
12
BIOBASED (BIOMASS OR RENEWABLE BASED)
Biobased (Biomass or Renewable) based Materials – Organic material/s
containing in whole or part biogenic carbon (carbon from biological sources)
Organic Material/s -- material(s) containing carbon based compound(s) in which the
carbon is attached to other carbon atom(s), hydrogen, oxygen, or other elements in a
chain, ring, or three dimensional structures (IUPAC nomenclature)
Biobased (carbon) Content -- The bio content is based on the amount of
biogenic carbon present, and defined as the amount of bio carbon in the plastic
as fraction weight (mass) or percent weight (mass) of the total organic carbon in
the plastic. (ASTM D6866)
% bio or biobased content = Bio (organic) carbon/total (organic carbon) * 100
ASTM D6866 – Standard Test Methods for Determining the Biobased Content of
Solid, Liquid, and Gaseous Samples Using Radiocarbon Analysis
Narayan
Take Home Message
– Use bio (carbon) content analysis (ASTM D6866) to
document verifiable CO2 reductions
– Intrinsic “material carbon footprint” reductions provides
the rationale for switching from a petro/fossil carbon
feedstock to a bio-renewable carbon feedstock
– Remember – LCA methodology provides the process carbon and
environmental footprint not material carbon replacement
footprint
– Process carbon footprint – impact of GHG emissions from the
various process step to convert the feedstock to final product
and ultimate disposal (cradle to grave)
Narayan
Carbon footprint reduction strategy using bio content Process Carbon Footprint – the LCA trap
14
Carbon Footprint Including Conversion
0
100
200
300
400
500
600
700
Starch/PLA PET PP (85.71%c)
CO2 released during coversion feedstock CO2 release
Narayan
Carbon footprint reduction strategy using bio content Biodegradability – A misused and abused term
15
Using biodegradability as an end-of-life strategy to completely remove
single use short life disposable products or chemicals from the
environmental compartment in a safe and efficacious manner via
microbial assimilation (microbial food chain)
Must provide information (using ASTM. EN, ISO Standards)
• Disposal environment (like composting, anaerobic digestor,
marine, soil or landfill??
• Time to complete biodegradation
• Degradable, partial biodegradable not acceptable – serious
health and environmental consequences
• Phil. Trans. Royal. Soc. (Biology) July 27, 2009; 364
Narayan
Carbon footprint reduction strategy using bio content Measuring biodegradability
16
Microorganisms extract chemical energy for use in their life processes
by the aerobic oxidation of glucose and other utilizable substrates –
BIODEGRADBLE PLASTICS, food waste, paper, forest residues
biological matter
Glucose/C-bioplastic + 6 O2 6 CO2 + 6 H2O; DG0’ = -686 kcal/mol
AEROBIC
ANAEROBIC
Glucose/C-bioplastic 2 lactate; DG0’ = -47 kcal/mol
CO2 + CH4
CO2 is the quantitative measure of the ability of the microrganisms present in
the disposal environment to utilize/assimilate the test C-bioplastic, which is
the sole C-source available for the microorganisms --
biodegradation/bioassimilation
Narayan
Carbon footprint reduction strategy using bio content Measuring biodegradability
17
0
10
20
30
40
50
60
70
80
90
100
0 20 40 60 80 100 120 140 160 180 200
Time (days)
% C
c
on
ve
rsio
n to
C
O2 (%
b
io
deg
ra
da
tio
n)
lag
phase
biodegradation phase
plateau phase
biodegradation degree
O2
Compost
& Test
Materials
CO2
Narayan
Carbon footprint reduction strategy using bio content
18
Biodegradability under composting conditions
• Specification Standards ASTM D6400, D6868, D7021
• Specification Standards EN 13432 (European Norm)
• Specification Standards ISO 17088 (International Standard)
Biodegradability under marine conditions
• Specification Standard D 7021
Biodegradability Test Methods – ASTM Standards
• Soil D5988
• Anaerobic digestors D 5511, ISO 15985
• Biogas energy plant
• Accelerated landfill D 5526
• Guide to testing plastics that degrade in the environment by a
combination of oxidation and biodegradation ASTM D 6954
Must provide results from the test methods – could be zero or 50 or 100 percent ---
generally not provided but claim of complete biodegradability made
Narayan
OECD BIODEGRADABILITY TESTS FOR CHEMICALS
Ready biodegradability
– “if a chemical meets the “ready biodegradability” standard (OECD 301-B) then it is
assumed that the chemical will undergo rapid and ultimate biodegradation in most
environments including biological STP’s and that in such cases, no further
investigation of (bio) degradability of the chemical, or of the possible environmental
effects of transformation products is normally required”.
Pass criteria 60% theoretical carbondioxide (ThCO2) (TG 301 B) to be reached in
a 10-day window within the 28-day period of the test - US EPA
Inherent biodegradability
– tests of inherent biodegradability have been designed to assess whether the
chemical has any potential for biodegradation under aerobic conditions.
– Biodegradation above 20% of theoretical (measured as BOD, DOC removal or COD)
may be regarded as evidence of inherent, primary biodegradability
Ultimate biodegradability
– test compound is totally utilized, 100% biodegraded by microorganisms resulting in
the production of carbon dioxide, water, mineral salts, and new microbial cellular
constituents (biomass).
Inherent biodegradability term usage is problematic and misused
especially as it applies to products
Includes:
Definition, content verification, ASTM D6866
Biodegradability using ASTM D6400 and D6868 (paper coatings)
D7021 (marine)
performance requirements; and
assurance that products are available
U.S. Farm Security and Rural Investment Act of 2002 (P. L. 107-
171), Title IX Energy, Section 9002
FARM BILL
Federal Procurement of Biobased Products – the “biopreferred program” (www.biopreferred.gov)
• develop guidelines for designating biobased products
• publish a list & issue criteria for a designated biobased products list (DBL)
for federal purchase;
• “USDA Certified Biobased Product” labeling program
Ramani Narayan, Michigan State University, www.msu.edu/~narayan
Ramani Narayan, Michigan State University, www.msu.edu/~narayan
BIO PRODUCT TECHNOLOGY EXEMPLARS
DuPont’s 1,3-PDO ---- polyesters (Sorona) & renewably sourced products like Hytrel thermoplastic elastomers, Cerenol polymers
NatureWorks –40,000 t (300 MM lbs) PLA
PURAC – Lactic, lactide, Thailand (100,000 t)
BASF – 14, 000 t biodegradable polyesters – biobased polyesters incorporating PLA; 60,000 t plant 2010)
Novamont -- Bioresins
Natur-Tec -- Bioresins
Braskem (150 MM lbs), DOW (250 MM lbs)
Solvay – 60, 000 tons ethylene, 110, 000 t EtOH PVC
ADM-Metabolix – Polyhydroxyalkanoates (PHA’s)
Arkema – Polyamide 11 – high performance polymers
Biopolyurethanes – Ford, Toyota
Biofiber composites – auto components
BioPET --- Coca Cola’s plant bottle
Several others
Ramani Narayan, Michigan State University
DISCUSSION SLIDES
Narayan
Carbon footprint reduction strategy using bio content Problems with incomplete and partial biodegradation
23
plastic pieces can attract and hold hydrophobic elements like PCB and DDT up to one million times background levels. As a result, floating plastic is like a poison pill
• From Algalita Marine Research Foundation – www.algalita.org/pelagic_plastic.html
PCBs, DDE, and nonylphenols (NP) were detected in high concentrations in degraded polypropylene (PP) resin pellets collected from four Japanese coasts.
Plastic residues function as a transport medium for toxic chemicals in the marine environment.
• Takada et al Environ. Sci. Technol. 2001, 35, 318-324
• Blight, L.K. & A.E. Burger. 1997. Occurrence of plastic particles in seabirds from the Eastern North Pacific. Mar. Poll. Bull. 34:323-325
• Phil. Trans. Royal. Soc. (Biology) July 27, 2009; 364
Thompson, R.C. et al. 2004. Lost at sea: Where is all the plastic? Science 304,
838, 2004
Narayan
Sorting through facts, hypes, claims (misleading)
GREEN WASHING
Narayan
Green Washing Claims -- Additive Technology
“Plastic products with our additives at 1% levels will fully biodegrade in 9 months to 5 years wherever they are disposed like composting, or landfills under both aerobic and anaerobic conditions”
The 50% Bio-Batch film did not degrade as completely or as quickly as the cellulose.
At the end of the test, 19% of the film had degraded.
The results of the aerobic degradation tests indicate that, in time, plastics produced
using Bio-Batch pellets will biodegrade in aerobic conditions.
DATA DOES NOT SUPPORT THE CONCLUSIONS!
Narayan
MISLEADING BIODEGRADABILITY CLAIMS
Narayan
MISLEADING CLAIMS – UNSUPPORTED BY DATA
Oxo-biodegradable polyethylene (PE) film claims – “The technology is based on a very
small amount of prodegradant additive being introduced into the manufacturing process,
thereby changing the behavior of the plastic and the rate at which it degrades. The plastic
does not just fragment, but is then consumed by bacteria and fungi and therefore
continues to degrade to nothing more than carbon dioxide, water and biomass with no
toxic or harmful residues to soil, plants or macro-organisms”
“Designed to interact with the microorganisms present in landfills, composters, and almost
everywhere in nature including oceans, lakes, and forests. These microorganism
metabolize the molecular structure of the plastic breaking it down into soil”
“Combined with an oxo-biodegradable proprietary application method to produce films for
bags. This product, when discarded in soil in the presence of microorganisms, moisture, and
oxygen, biodegrades, decomposing into simple materials found in nature. Completely
breakdown in a landfill environment in 12-24 months leaving no residue or harmful toxins
and have a shelf life of 2 years”
In each of the above cases scientific substantiation showing carbon conversion to CO2
using established standard test methods NOT PROVIDED
Narayan
BIODEGRADABILITY CLAIMS
Chem. Commun., 2002, (23), 2884 - 2885 – A hypothesis was developed, and successfully tested, to greatly increase the rates of
biodegradation of polyolefins, by anchoring minute quantities of glucose, sucrose or lactose,
onto functionalized polystyrene (polystyrene-co-maleic anhydride copolymer) and measuring
their rates of biodegradation, which were found to be significantly improved
PRESS Sugar turns plastics biodegradable. Bacteria make a meal of sweetened polythene
and polystyrene.
weight loss of only 2-12%,
Only sugar is being assimilated, PE
chain intact – Is this a genuine
example of biodegradable plastic?