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How Might Biofuels Impact the Chemical Industry?

Posted on: Wednesday, 26 March 2008, 03:00 CDT

By Banholzer, William F Watson, Keith J; Jones, Mark E

Considering the range of possibilities and constraints, a major transformation of the chemical industry's current capital structure is unlikely for at least a few decades. The chemical industry is a critically important contributor to modern society, providing the raw materials for a staggering 70,000 products ranging from the chlorine used to purify water to the lightweight materials that comprise sporting goods (1). As a whole, the industry uses a significant amount of fossil fuel as energy to carry out the desired transformations and separations, and as the source of basic carbon building blocks. Thus, the energy sector and the chemical industry are intimately linked.

As energy demand steadily increases worldwide and the price of oil hovers around the psychologically important level of $100/bbl, the search for economically viable and environmentally benign alternatives - long the domain of the chemical engineering profession - has intensified. Hydrogen, nuclear, wind, solar and biofuels such as ethanol and biodiesel are being pursued as potential alternatives to conventional fossil fuels (2, 3). Although each has positive and negative attributes, the biofuels sector has garnered the most attention and has witnessed incredible growth in recent years.

The net benefit to society of a robust and large biofuels sector is still a matter of debate, however. The United Nations recently issued a policy statement calling for a five-year moratorium on the use of food crops for the production of fuels (4). At the same time, the U.S. Congress passed and President Bush signed into law an energy bill that calls for an increase in the use of biofuels (5). That these respected institutions hold such diverging opinions is evidence that this issue is both critically important and poorly understood.

What would be the potential impact of rising production and use of biofuels on the chemical industry? This question has received scant attention in the literature. Ultimately, the production of chemicals from biologically derived feedstocks must be driven by sound economics and the ability to meet desired technology/ performance objectives.

This article provides insight into the potential of alternative feedstocks - with an emphasis on biofuels to serve as the key raw materials for chemical production. It focuses on the production of ethylene from bioderived ethanol, because compared to some alternatives that are being pursued, this is the most viable and straightforward potential feedstock replacement, and constraints discovered for this process will most likely be more severe for other alternatives. The discussion that follows also outlines the nature of the relationship between fuels and chemicals, and details recent changes in biofuels output. It then considers some environmental considerations and basic thermodynamic issues. Finally, this article showcases the key issues around scaleup, capital costs, variable costs, project decision-making, and the prospects for technological innovations that could materially change the analysis. We conclude that - given the prevailing technical, environmental and financial opportunities and constraints - a dramatic realignment of the chemical industry away from traditional feedstocks toward biofuels is highly unlikely to be realized over the next few decades.

Chemicals and fuels

Ethylene and propylene serve as the basic building blocks from which most polymers and chemical intermediates are made today (6). Both of these intermediates are produced by the high-temperature, gas-phase cracking of alkane feedstocks steam is used as a diluent in the steam cracking process, and external heat obtained from the burning of natural gas and process off-gas is applied to furnace tubes.

Typical feedstocks for steam cracking include ethane, propane and naphtha. These are obtained as purified products from natural gas processing and petroleum refining. When not used as chemical feedstocks, these materials find use as fuels.

The proportion of petroleumderived fuels that end up being used as chemical feedstocks accounts for roughly 1% of the total global energy market, or about 3% of the global oil and gas market. The chemical industry is quite efficient with the raw materials it utilizes during production, retaining a large fraction of the purchased feedstock in the end products it produces - typically about half of the energy and three-quarters of the mass.

Conversion enthalpy and separations - which are still dominated by distillation - account for the majority of the energy losses during petrochemical processing. These also represent a significant portion of the investment needed to build a plant. In fact, it is commonly estimated that 40-70% of both the capital and operating costs required during typical petrochemical processing are for separations (7).

The challenging separations required during steam cracking are accomplished by cryogenic distillation. Hydrogen, methane, olefins and other components typically exit the cracking furnaces at temperatures above 700[degrees]C, only to be compressed and cooled to cryogenic temperatures to allow the desired fractions to be separated by distillation. Despite this energy inefficiency, one redeeming quality of the cracker/separation train is that it scales exceedingly well. It is this characteristic that has allowed cracker complexes to increase in size in recent years, with the largest now being over 2,000 gigagrams per year (Gg/yr) (8).

Polyethylene production currently accounts for approximately 60% of the global ethylene consumption. It is followed by ethylene oxide, vinyl chloride and styrene. Most ethylene oxide is converted to ethylene glycol and is ultimately used to produce polyethylene terephthalate for bottles and polyester fiber. The vast majority of vinyl chloride ends up in polyvinyl chloride for use in construction. Ethylene glycol and vinyl chloride are easily shipped, and there is a vibrant global trade in both commodities. This allows the polymers derived from them to be manufactured globally.

Ethylene, in contrast, is difficult to ship, and the ethylene derivatives, including polyethylene, are most commonly produced at the cracker fenceline or at a facility next to a pipeline. As a result, the trend toward larger-scale production and the need for access to massive quantities of alkane feedstock have driven most new investment in ethylene production to the Middle East (8).

Chemicals and biofuels

Today, bio-derived polymers are commercially available, but only on a small scale (9). To date, there are no large-scale biologically derived aromatic materials used by the chemical industry.

Polymers derived from renewable plant-based feedstocks are garnering attention throughout the chemical engineering community due to concerns over climate change, increases in fossil energy prices, and the desire to increase the geographic flexibility of feedstock sources. Biopolymers produce between 0.8 and 3.8 fewer kg of CO2 per kg of polymer compared to conventional fossil-derived polymers (9). Although biopolymers can be an attractive option for serving local markets and bolstering local economies, their material properties and characteristics (in terms of strength, heat and chemical resistance, and so forth) are usually inferior to those of their traditional, ethylene-derived counterparts, so they have not been readily accepted in the market, and their use tends to be limited to a relatively small range of end-use applications.

Recent announcements have illuminated another possibility: production of polymers using bio-derived ethylene as the starting material. Separately. Braskem (10), and a joint venture between Dow Chemical and Crystalev (11), have announced plans to make polyethylene products using ethylene obtained from the dehydration of ethanol at world scale. Of course, the polymers made by this approach will be exactly the same as those derived from fossil sources, with the advantageous exception that they are made from a renewable feedstock. While these facilities make sense in Brazil - where ethanol production costs are reasonable and the market is well developed - it will be difficult to implement this approach globally on a large-scale basis.

Ethanol is currently the most abundant biofuel and is well- suited for use as a chemical feedstock due to the ease and selectivity with which it can be converted to ethylene. Ethanol dehydration to ethylene over acidic catalysts is a well-known commercial process. Brazil and the U.S. currently produce the vast majority of the world's fuel ethanol. In Brazil, plentiful, indigenous sugarcane provides the raw material for the thriving ethanol industry, whereas in the U.S., corn is the feedstock of choice for today's growing ethanol production infrastructure.

Both routes have seen robust commercial-scale growth over the last decade. Despite this growth, however, ethanol still meets only 12.6% of the demand for gasoline in Brazil and just 3.5% of current U.S. gasoline demand (12) - representing less than 1 % of the world's total transportation fuel use.

In Brazil, ethanol is truly considered a primary transportation fuel (with a widely available infrastructure in place to support consumer automotive use), and in terms of cost, it trades at parity with fossil fuels on an energy basis. By contrast, in the U.S., ethanol is still used largely as a fuel additive, blended into certain gasoline pools to meet a federal mandate related to the phaseout of methyl tert-butyether (MTBE) as a fuel oxygenate. Over the last several years, ethanol has had a premium price tag associated with it - having been priced at between one and three times the cost of gasoline blend stock. Ethanol will only become a competitive feedstock for conversion to ethylene when it consistently trades at energy parity with fossil feedstocks. In recent years, other bio-derived feedstocks have been attracting investment dollars as well, with several companies having announced seed-oil-based polyol replacements. For instance, soy-based polyols are being used to replace propylenebased polyether polyols in urethane foams. Similarly, the rapid growth in biodiesel production has spawned several projects based on glycerin (13), a side-product of seed-oil processing for biodiesel and other applications. Solvay and Dow Chemical have also announced plans to convert glycerin to propylene chlorohydrin, followed by saponification to epichlorohydrin. Archer Daniels Midland (ADM). Dow, Cargill, and others are pursuing commercial-scale facilities to produce propylene glycol from glycerin, which is the primary byproduct of biodiesel production (CEP, Aug. 2007. pp. 6-9).

Figure 1 shows the current worldwide industrial volume of carbonbased fuels and feedstocks (14-17). seed oils and olefins (ethylene and propylene) are produced in higher volumes than biofuels (ethanol and biodiesel), yet all three still pale in comparison to the production of traditional fuels, shown here as petroleum derived distillate.

Environmental impacts

Biofuels receive considerable attention as a means to mitigate anthropogenic carbon emissions associated with transportation. The use of fuel for transportation returns carbon to the atmosphere in the form of CO2. In fact, recent studies have questioned whether biofuels are worse for global warming than traditional fossil fuels (15). Chemical production, on the other hand, seeks to preserve the carbon atoms contained in the fuel by converting them into products that are, for the most part, durable goods - in effect, sequestering the carbon and resulting in a net reduction of atmospheric CO2.

Thus, the use of biofuel as chemical feedstock may someday help to offset carbon emissions and could incur a benefit, should carbon emissions be taxed. However, arable land is a finite resource, and transforming the chemical industry toward biofuels would further strain this valuable asset.

Basic thermodynamics

Since carbon exists in a rich variety of forms, fundamental thermodynamics principles should guide the search for alternative feedstocks. Figure 2 plots the enthalpy of combustion versus the oxidation state of carbon for a variety of compounds (19, 20). Methane, in the upper left. is the most energetic carbon molecule - i.e., per unit mass, it will release the most heat when burned. At the other extreme (lower right) is CO2, which is totally oxidized.

Modern chemical processes are based on oxidation because they have lower costs and conserve more of the carbon in the feedstock. Reducing carbon (moving up the chart) requires energy (cost) from an external source (other molecules, light, electricity, heat) or a reapportionment of the internal energy, as in fermentation.

Biological systems reduce oxidized, lower-enthalpy carbon atoms in carbohydrates to ethanol by further oxidizing 33% of the carbon atoms to CO2. The simultaneous oxidation and reduction inherent in fermentation results in an overall poor carbon efficiency.

Starting with higher-energy feedstocks (such as oil and gas) that are structurally closer to the desired end products requires botfi less energy input and fewer steps to conduct the desired transformations. These two factors translate into lower cost. Thus, it was simple cost optimization based on thermodynamics that motivated the chemical industry to migrate almost exclusively to oil and natural gas as their carbon feedstocks.

Cropland requirements

In general, photosynthesis does a relatively poor job of converting solar energy into chemical energy during plant metabolism (as measured by the heat of combustion of dry biomass), and under no circumstances can the energy content of the biomass exceed the input solar energy. In fact, the conversion efficiency of plants is only a small fraction - typically 0.1 to 1 % - of the input solar flux (21, 22).

Net primary productivity (NPP) is a measure of actual biomass production in a given ecosystem. NPP values illustrate the stark contrast between tropical and temperate climates: tropical NPP values are in the range of 900-1,200 g-[degrees]C/m^sup 2^-yr, while values in temperate regions vary from 300 to 500 g-[degrees]C/m^sup 2^-yr (23). Maximum chemical production capacity using biomassbased feedstocks is thus bounded by these NPPs.

Unfortunately, not all of the NPP can be harvested, and that which is harvested is only partially converted. The relative inefficiency of photosynthesis is evident in Figure 3, which examines a grain-producing plant in a temperate climate (24).

Consider replacing today's global ethylene production with ethanol dehydration. Ethanol yield from Brazilian cane is estimated to be approximately 6,080 L per hectare (L/ha), whereas ethanol yield from U.S. corn is approximately 4,070 L/ha. Synthesizing 116,200 Gg of ethylene - the estimated 2007 worldwide consumption (25) - would require 242 billion L of ethanol, or nearly 40 million ha in Brazil or 60 million ha in the U.S. Brazil currently uses about 66.6 million ha of cultivated land for all crops (26), whereas the U.S. uses approximately 178.8 million ha (27). Hence, replacing the global ethylene chain alone would require approximately 60% of Brazilian, or 34% of U.S., cropland. Using dedicated energy crops such as switchgrass would do little to ease the land requirements, as estimated yields are on the order of 5,600 L/ha, less than current ethanol yields in Brazil.

While there is sufficient cropland to transition much of me global chemical feedstock base to agriculturally derived starting materials, is such a conversion likely? Today's cropland is primarily used to support the global need for nutrition. As the world population continues to increase, more food production will be needed from existing land assets. Global mandates for renewable fuel usage might also garner priority over chemicals, assuming they are enforced. Absent new mandates for chemical production from renewables, it seems unlikely that the required cropland will become available. Further, using land other than preexisting cropland for these purposes could potentially have a net negative effect on global warming (15).

Thus, despite optimization over several millennia, photosynthesis is still a poor energy conversion process. This leads to excessive land mass requirements that are unreasonable given the competition for food and fuel. This will likely not be changed by technological breakthroughs unless the fundamental photosynthesis process is reinvented or augmented.

The need for capital

Few enterprises have the financial, technical and marketing expertise to build and profitably run complex chemical plants - regardless of what feedstock is used. These companies have limited capital budgets and spend them with great care.

The top 50 chemical companies spent an estimated combined $39.7 billion on capital in 2006 (28). This budget was earmarked to support an entire portfolio of projects, including the following (in order of increasing risk):

* support and/or augmentation of existing facilities

* investment in new facilities that serve an existing market using mature technology

* investment in new facilities that serve an existing market using new technology

* investment in new facilities that serve a new market using new technology.

The use of ethanol for the production of ethylene would most likely fall between the second and third categories - even though each process step is known, a fully integrated combination has yet to be constructed.

An interesting analysis involves making a series of optimistic assumptions about capital expenditures and then predicting the resulting market penetration of bioderived chemicals. For example, we developed a scenario analysis out to the year 2020 using a combination of published data (29), internal estimates of ethylene market growth, and the following assumptions:

* the capital budget of the top 50 chemical companies grows at 5%/ yr

* the proportion of that budget spent on bio-derived ethylene grows linearly from near zero in 2007 to a full 10% in 2020

* the cost of these new integrated facilities is $2 million per Gg of capacity

* advances in biotechnology enable the capital costs to remain flat over the 2007-2020 timeframe.

As shown in Figure 4, under this scenario, the predicted market penetration for bio-derived ethylene is still only slightly more than 12%. The scenario can be perturbed, but finding realistic situations in which larger market share is achieved is a challenge. Furthermore, by 2020, investment in bioderived ethylene would surpass that needed to supply the predicted annual incremental growth, which triggers a new set of economic analyses (discussed later).

Figure 5 summarizes the land and capital required to replace the chemical ethylene base using a variety of methods. Since no integrated ethanol-to-ethylene plants currently exist, capital requirements are estimates and are listed on the figure. Error bars of +-20% for capital and +-10% for land are included to account for uncertainties, and U.S. cropland equivalent is shown for comparison. As expected, combined cane/bagasse or corn/cob cellulosic ethanol- to-ethylene plants require more capital investment but less cropland. Standalone cellulosic ethanol-to-ethylene would require significantly more capital than the other methods analyzed. Variable costs

When choosing among feedstocks, variable cost is an important consideration. As a first-order approximation, the cost of key raw materials as a function of their energy content can be used. A complicating factor is that prices for different products are based on different units.

Figure 6 plots the market price of several important chemicals corrected for energy content (higher heating value). This visual representation allows for quick comparison of products using their traditional units but calibrated to $/GJ.

Keep in mind that prices vary over time. The prices shown here are snapshot estimates based on quotes from various public sources in late 2007.

Biomass at $50/m.t. is cheaper than corn at $3.76/bu and ethanol at $1.76/gal. This increase in price per unit energy progressing down the value chain is consistent - otherwise, it would be impossible for converters to turn a profit.

A similar pattern of rising prices down the value chain can be seen withethane-to-ethylene-to-polyethylene in the U.S. Also evident from Figure 6 are the significant regional price differentials that are driving current investment decisions. Ethane in the Middle East is much cheaper than in the U.S. In fact, for corn ethanol to compete with Middle East ethane on an energy basis, it would have to sell for amere $0.15/gal.

Ultimately, there exists a fundamental trade-off between variable and capital costs. Figure 7 plots capital costs versus variable costs for several olefin production technologies (all at the 1,000 Gg/yr scale). The diagonal lines represent approximate economic- cost-of-production equivalency curves.

Coal-to-olefins production via gasification has a high capital intensity but very low variable costs. By comparison, integrated ethanol-toethylene plants cost less to build but more to run. If minimization of cost variability over the lifecycle of the facility is a primary objective, then the coal-to-olefins route may be a more appropriate choice - once the plant is built, the material cost becomes low relative to depreciation, which is known and constant. However, the scale of the required investment invariably means that other projects will not get funded due to capital budget limitations. Alternatively, low-capital/high-variable-cost plants can be risky enterprises, since even small changes in variable costs can have a large impact on overall plant profitability in the long run.

The imposition of a carbon tax seems inevitable - although the key unresolved issues include which governments will impose this tax, and to what extent. Implementation will be complicated given the diverse nature of production facilities that currently exist. Figure 7 includes estimates of the potential impacts of a CO2 tax on the various technologies.

Consider that coal-to-olefins using synthesis gas technology could produce upwards of 5-7 Gg of CO2 per Gg of prime olefin (30, 31), while traditional cracking of naphtha and ethane produce significantly less (0.5-3 Gg of CO2 per Gg of olefin, depending on source and method) (32). Viewed in isolation, fermentation ethanol facilities are significant CO2 emitters, although such facilities are likely to be exempt from regulation.

The arrows extending to the right of each technology estimate the impact, respectively of a CO-, tax of $25, $50, $75. $100, and $125 per m.t. OfCO2. The analysis assumes 5 Gg of CO2 per Gg of olefin for coal-based processes, 2:1 for natural gas fractionation and cracking, 2:1 for naphtha cracking, and 1:1 for ethane cracking. Clearly, as shown in the figure, the coal-gasification-toolefins approach would be impacted most dramatically by a carbon tax of any magnitude.

The replacement decision

In order to move beyond incremental growth, the production of bio- derived chemicals would have to offer significant advantages over existing chemical facilities to justify the double decision of "build new and shutdown old." A simple time value of money (net present value. NPV) analysis can give insight into the magnitude of the savings that would be needed. Many companies use a specific internal discount factor that varies depending on the nature of the project and the capital structure of the firm. This analysis uses 13%, which is in the range for projects of this type.

Assume that a 1,000-Gg (per year) bio-derived-ethanol-to- ethylene plant costs $2 billion to construct. To justify this expenditure, the new plant would have to save roughly $370,000 of cash cost per Gg of ethylene to achieve a breakeven return on the capital investment in 10 yr (based on a 13% discount factor). This is the minimum cash saving required, since companies typically will not undertake many zero-NPV capital projects.

According to a recent analysis, the global average cash cost for all ethylene facilities is less than $700,000/Gg. and most facilities in the Middle East have a total cash cost of less than $400,000/Gg (33). Thus, it is extremely unlikely that bioethanol-to- ethylene plants can produce sufficient savings to justify shutdown economics - even as hydrocarbon costs continue to rise.

The imposition of a carbon tax could materially alter these replacement economics. For example, assume that a 1,000-Gg traditional natural gas fractionation and cracking plant emits 2 Gg of CO2 per Gg of prime olefin. The similarly sized integrated ethanol-to-ethylene plant would become a viable candidate for replacing the cracker at a carbon tax of approximately $ 185,000 per Gg of CO2 ($185 per m.t., assuming the ethanol-to-ethylene plant is exempt from taxation).

There exists a critically important but subtle difference between projects that are viable and those that are likely to get funded. For example, many studies point to the viability of coal-to-fuels plants in the U.S. A recent study by Nexant and the National Energy Technology Laboratory concluded that such a facility could profitably operate at oil prices above $37/bbl (34). Despite this, no such facility has yet been constructed in the U.S. Once again, the key issue is that few companies have the expertise to build and operate these plants, and absent significant government intervention, they have a plethora of more-profitable, less-risky projects to fund. The situation for biofuel-tochemicals is similar.

The competitive bar is always the best available alternative. At the present time, significant regional price differentials for fossil feedstocks have driven investment to low-cost regions such as the Middle East, where very profitable plants can be run using mature technology. Only when these price differentials dissipate will the playing field become level.

Technology advancements

Technical innovations will continue to impact biofuels production and. with it, the impact that biofuels can have on the chemical industry. Today's generation of biofuels will undoubtedly be joined or replaced by second- and third-generation technologies. For example, yield can be improved in conventional processing by increasing the relative amount of fermentable sugar or starch as a percentage of the total biomass. Crop yields have improved by moderating metabolic pathways, forcing the plant to devote more of its energy to creating sugars or seed (35).

What remains largely unchanged is the net primary productivity of the plants that make up today's most viable biomass sources. There is considerable evidence that plants have not dramatically improved their net primary productivity in millions of years, in spite of the advantages that such an improvement is likely to impart (36). The total energy stored in a plant is still governed by the overall inefficiency of photosynthesis.

Processing of lignocellulosic biomass, generally considered a secondgeneration fuel, could lead to further ethanol yield improvements. Cellulosic ethanol likely will be implemented in addition to current ethanol production, thereby increasing yield per unit area. However, this will also require more expensive facilities, raising the bar on the cost savings required to justify building the new plants.

In general, the capital efficiency of fermentation is highly optimized. Capital efficiency can be gained by reducing capital costs or improving throughput. Modification of organisms to increase fermentation productivity, improve separation efficiency, and achieve higher alcohol titers would likely improve capital efficiency. For chemical use, drying is not required. Scale is something that is difficult to expand. Cane has a critical cut-to- crash time that limits the range over which it can be efficiently transported. Corn-based ethanol plants are limited due to transportation costs. The scales of both types of facilities are commonly around 380 million L (300 Gg).

Thermochemical biomass conversion technology that does not produce ethanol does not necessarily have many advantages for chemical production. Pyrolysis-based methods produce aromatic materials that are not particularly useful for olefin production. Gasification offers the option of producing mixed alcohols, Fischer- Tropsch liquids or gasoline. Of these, the mixed-alcohols process appears most viable as a source of feedstocks for chemicals.

Concluding thoughts

The chemical industry evolved to its current state for sound economic and thermodynamic reasons. Despite rapid and unprecedented increases in the price of fossil fuels, major change to the existing capital base (to support a widespread change from fossil-fuel-based to bio-based approaches) does not appear imminent. Although theoretically possible, the utilization of biofuels as a primary feedstock for production of commodity chemicals will most likely be constrained by a shortage of cropland, limited capital, and the availability of lower-cost alternatives. Absent unforeseen technological innovations or significant government mandates, this situation is unlikely to change on a wholesale basis in the coming decades. Literature Cited

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WILLIAM F. BANHOLZER, KEITH J. WATSON AND MARK E. JONES

THE DOW CHEMICAL CO.

WILLIAM F. BANHOLZER, PhD, is corporate vice president and chief technology officer for The Dow Chemical Co. (2030 Dow Center, Midland, Ml 48674; Phone: (989) 636-1000; E-mail: cto@dow.com). He is a member of Dow's Management Committee, chairs the company's Innovation Committee, and leads Dow's research and development activities around the world. Before joining Dow, he had a 22-year career with General Electric Co., where his last position was vice president of global technology at GE Advanced Materials, responsible for worldwide technology and engineering. In 2002, Banholzer was elected to the U.S. National Academy of Engineering, one of only 105 active chemical engineers elected to the prestigious organization, and in 2006 was elected to serve on the Academy's governing body. He holds a BS in chemistry from Marquette Univ. and MS and PhD degrees in chemical engineering from the Univ. of Illinois. He is a certified six sigma master black belt, holds 15 U.S. patents, and has over 80 publications in the fields of engineering and chemistry. He is a member of AIChE and the American Chemical Society.

KEITH J. WATSON is the technology strategy development leader for Global R&D at The Dow Chemical Co. (Building 1776, Midland, Ml 48674; Phone: (989) 6361000). His research areas of interest include catalysis, energy, and alternative feedstocks. He has held several other research positions at Dow since joining in 2001. Watson received a BSc degree in chemistry from Canada's Mount Allison Univ. and a PhD in chemistry from Northwestern Univ. He holds three U.S. patents and has co-authored 13 publications.

MARK E. JONES is the technology strategy development scientist for Basic Plastics and Chemical/Hydrocarbons and Energy R&D at The Dow Chemical Co. (2020 Dow Center, Midland, Ml 48674; Phone: (989) 636-1000). Much of his career has been spent in the company's Core R&D Chemical Sciences group, where his work has been primarily in the area of oxidation catalysis. His projects have included production of dimethyl carbonate via oxidative carbonylation, selective hydrogenation of chlorocarbons, hydrogen production for portable fuel cell applications, and vinyl chloride production from ethane. More recently, he has participated in developing alternative feedstock options based on both fossil and renewable feedstocks, (ones holds a BS in chemistry from Randolph-Macon College, and a PhD from the Univ. of Colorado - Boulder. He is the author of over 16 issued U.S. and European patents.

Source: Chemical Engineering Progress

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