Catalytic Partial Oxidation of Isobutanol for the Production 

of Hydrogen

by Jeffrey G. St. Clair, Ivan C. Lee, and Adam S. Gamson

ARL-TR-5732 November 2011

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Army Research Laboratory 

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ARL-TR-5732 November 2011 

Catalytic Partial Oxidation of Isobutanol for the Production 

of Hydrogen 

Jeffrey G. St. Clair, Ivan C. Lee, and Adam S. Gamson 

Sensors and Electron Devices Directorate, ARL 

Approved for public release; distribution unlimited. 
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Catalytic Partial Oxidation of Isobutanol for the Production of Hydrogen

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Jeffrey G. St. Clair, Ivan C. Lee, and Adam S. Gamson

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14. ABSTRACT

Catalytic partial oxidation of isobutanol was investigated at various contact times, as were equivalence ratios, for the purpose of 

H2 production. The reactor was tested using a γ-Al2O3-coated foam as a catalyst, as well as a similar foam with rhodium (Rh) 

added. Both catalysts achieved isobutanol conversion greater than 99% at an operating temperature of 500 °C for a contact 

time of 25 ms. The results show little H2 is produced when the Rh is absent, whereas selectivities as high as 62.92% were 

achieved with the noble metal present. The alumina catalyst also displays no complete combustion regime for fuel lean 

combustion; instead, olefins, carbon dioxide (CO2), and water are the dominant products at all equivalence ratios. With 

approximately 8.25 W of isobutanol, 3.61 W of H2 can be attained with the Rh catalyst for use in small power devices, such as a 

proton exchange membrane fuel cell.

15. SUBJECT TERMS

Isobutanol, combustion, partial oxidation, hydrogen

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Ivan C. Lee

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iii

Contents 

List of Figures iv

1. Introduction 1

2. Experimental 2

3. Results 5

4. Discussion 9

4.1 Reaction Pathway ............................................................................................................9

4.2 Hydrogen Production ....................................................................................................11

4.3 Temperature Profile .......................................................................................................11

5. Conclusions 12

6. References 13

Distribution List 14
iv

List of Figures 

Figure 1. Schematic of adiabatic reactor (not to scale). ..................................................................3

Figure 2. Hydrogen selectivity of the reactor products for a contact time of (a) 70, ( b) 135, 

and (c) 270 ms using the alumina catalyst (i.e., without rhodium). ..........................................6

Figure 3. Hydrogen selectivity of the reactor products for a contact time of (a) 70, (b) 135, 

and (c) 270 ms using the rhodium catalyst. ..............................................................................7

Figure 4. A H2 produced per amount of isobutanol at various contact times and equivalence 

ratios. ..........................................................................................................................................8

Figure 5. Temperatures recorded at the backface of the catalyst are given with solid lines. 

Dashed lines represent isobutanol conversion to other species. Contact time: 70 ms. .............8
1

1. Introduction 

As technology improves, power requirements increase with a decreasing size envelope. 

Although batteries can provide power for small applications, such as personal electronics or 

small unmanned aerial vehicles (UAVs), they generally cannot provide it for an extended amount 

of time. To this end, much research has been invested into alternative sources of power with a 

longer endurance. One alternative is a fuel cell. Fuel cells employ the high gravimetric energy 

density of H2, but this fuel needs to be stored in a manner that does not dampen the effective 

energy density of the power system. Storing enough gaseous hydrogen (H) for long-duration 

operation requires a high-pressure, heavy storage tank, increasing system mass to unacceptable 

levels for small scale applications. Instead, liquid, energy-dense fuels can be reformed to 

produce H2, which can then be fed directly to the fuel cell. Therefore, an improvement in H 

production will lead to the advancement of smaller and smarter technology. 

Several fuels are being investigated for fuel processing applications, including alcohols like 

methanol and ethanol. Salge et al. investigated the catalytic partial oxidation of ethanol and 

ethanol-water mixtures; high H selectivities (above 80%) were achieved using a rhodium (Rh)-

ceria (CeO2) catalyst at short contact times (~10 ms) (7). This catalyst has also been used to 

reform methanol, 1-propanol, and 2-propanol with similarly promising high H2 selectivities (8). 

It was found, however, that without the Ceria coating, the reactor operated at higher temperatures 

with less successful results. This could mean that the Rh requires certain catalytic reactions to 

take place before it can produce the desired H2, and that these reactions occur on the surface of 

the support coating. 

Little work has been done in the catalytic reforming of heavier alcohols, such as butanol. 

Butanol isomers are an attractive renewable fuel source; the alcohol can be synthesized using 

yeasts or bacteria, such as E. coli (1–4). Butanol has a higher energy density than both methanol 

and ethanol, and a lower hygroscopicity, easing the issues of storage and transport associated 

with ethanol. Previous work by Behrens et al., however, reports that ethanol has a higher H2

selectivity than 1-butanol when using Rh/alumina as a catalyst (5). 2-butanol has been 

decomposed using a Pt/ZrO2 catalyst for H production (12). It was found that at temperatures 

below 275 °C, dehydrogenation is the dominant decomposition pathway; but above this 

temperature, dehydration occurs to produce water instead of H2. This change was attributed to 

carbon build-up on the catalyst surface and the alkenes blocking interfacial sites. Isobutanol has 

been the preferred fuel to synthesize recently, due to its high yield production (1). Branchedchain alcohols also are known to have higher octane numbers than the straight-chain isomers. 

Taylor et al. formed linear and branched butenes from isobutanol by dehydrating it over gammaalumina catalysts (6). These butenes could be further used to create other fuels like gasoline and 

butyl rubber. 
2

In catalytic conversion, the time the reactant has to react with the surface has been shown to play 

a prominent role in product composition (7–9). The contact time, when considering a monolithic 

foam, is determined by the volume of the foam, the volume flow rate of the reactants, and the 

operating temperature of the catalyst foam. With a large enough contact time, the chemistry 

within the reactor will reach its equilibrium condition. When operating at shorter times, 

however, intermediate molecules will still be present in the exhaust. The kinetic pathways at 

these contact times then play a greater role in what is produced. 

The equivalence ratio (), which compares the actual fuel-to-air ratio of the reactor to the 

stoichiometric fuel-to-air ratio, also plays an important role in fuel reforming. A -value of unity 

signifies a stoichiometric feed of fuel and air, which, for butanol, is given as 

CH3CH2CH2CH2OH + 6 O2  4 CO2 + 5 H2O ΔH = -2713 kJ/mol. (1) 

The -value can be controlled by adjusting the amount of fuel and/or oxygen (O2) fed to the 

reactor. A condition where the -value is greater than unity is considered “fuel rich,” and 

incomplete combustion occurs because not enough O is present to combust the entire amount of 

fuel; the incomplete combustion process is also known as partial oxidation. Running slightly 

fuel rich (1<<3) is usually the optimum condition for H2 production. Low -values (between 

zero and one) indicate a “fuel lean” environment that has more than enough O to oxidize all the 

fuel into its stoichiometric combustion products. 

This work investigates isobutanol reforming in an adiabatic, catalytic reactor to form H2 suitable 

for applications such as fuel cells. The effect of adding Rh to the γ-alumina monolith foam for 

improved performance is also a subject of interest. Using each catalyst, a wide range of 

equivalence ratios including both fuel lean and fuel rich regimes, at multiple contact times, is 

investigated. 

2. Experimental 

Figure 1 is a schematic of the cylindrical quartz reactor. Nitrogen (N) and O gases were 

premixed and introduced near the top of the reactor; the flowrates of the gases were controlled 

using mass flow controllers. Liquid fuel entered the reactor via a stainless steel tube with outer 

and inner diameters of 1.70 mm and 1.20 mm, respectively. The fuel is electrically conductive 

enough that it can be injected using low power electrospray techniques (10). Electrospray of the 

fuel in cone-jet mode was employed by creating a voltage difference between the droplet source 

and a neutral grounded mesh (~3300 V). When operated in cone-jet mode, charged liquid 

particles are emitted with a narrow droplet size distribution, which allows for a steady state 

evaporation rate to be established. The grounded tantalum mesh was placed a distance of 1 cm 

below the fuel inlet. An inert foam mixer was placed directly under the grounded mesh to aid in 

mixing the fuel vapor with the incoming N and O gases. This foam also aided in providing gas 
3

flow uniformity. The mixing foam was 1 cm in thickness. The inner diameter of the reactor was 

2 cm. 

Figure 1. Schematic of adiabatic reactor (not to scale). 

The catalyst was located 12.5 cm below the grounded mesh. Blank alumina foams (45 ppi) with 

a thickness of 1 cm were placed above and below the catalyst. The foams primarily acted as heat 

shields but also as another mixing layer to ensure uniformity of the fuel vapor over the entire 

catalyst surface. Two types of catalysts were tested. Both were built using an alumina monolith 

foam (Vesuvius, 80 ppi, 17 mm diameter, 1 cm thick), which was coated with -alumina to 

roughen the foam surface and to increase the surface area. The foams were calcined in a box 

furnace at 700 °C for 15 h. One of the foams was set aside at this point, and will be referred to 

as the alumina catalyst. An aqueous Rh(NO3)3 solution was added to the other foam, and the 

resultant foam was again calcined in the box furnace at 700 °C for another 15 h. This foam will 

be referred to as the Rh catalyst. The foam contained 0.07353 g of Rh and was prepared in the 

manner detailed in the literature (11). 

Sufficient heat was supplied via heating tape to the grounded mesh and mixing foam (generally a 

few degrees above the boiling point of the fuel) to ensure complete vaporization and catalytic 

ignition. Typical catalyst ignition temperature was approximately 240 °C. Below the heating 

tape, insulation was wrapped around the reactor—including the catalyst portion—to impose 

adiabatic conditions. Temperatures were observed at the nozzle, ground mesh, and catalyst, and 

were used just as a reference. The effluent gas exits the reactor, where it is sent through an 

Agilent four-channel micro gas chromatograph (GC). 

These GC measurements are vital in determining how much H is being produced and what other 

byproducts may also be present. The amounts of H, O, N, carbon monoxide (CO), CO2, and 

methane, ethylene, ethane, acetylene, propane, propylene, 2-butyne, butane, isobutane, 1-butene, 

t-2 butene, c-2 butene, isobutylene, 1,2-butadiene, 1,3-butadiene, pentane, ethyl acetylene, 1-

pentene, t-2 pentene, c-2 pentene, hexane, 1-hexene, t-2 hexene, and c-2 hexene were monitored 

using the four-channel micro-GC. Before each experiment, N was passed through the reactor to 
4

clear out any lingering gases and to ensure no leaks in the system. Heating tape was activated to 

provide heat to the region between the fuel atomizer and the catalyst. Then the appropriate N 

and O flow rates were set to give the equivalence ratio and contact time desired. Once the 

temperatures reached a steady state, the voltage differential between the ground mesh and the 

stainless steel tube was established to electrospray, and fuel flow was initiated. Voltages were 

then adjusted to maintain electrospray stability in cone-jet mode as needed. The temperatures 

were again allowed to reach a steady state operating condition, and the GC recorded the effluent 

gas composition during this time. 

Equivalence ratio and contact time are the two operating parameters that were varied while 

investigating the alumina and Rh catalysts. The equivalence ratios tested ranged from very fuel 

lean ( = 0.17) to fuel rich values up to  = 6.34. The equivalence ratio set the total O flow rate, 

using a set fuel flow rate, which was generally 1 mL h–1. At higher  values, the O flow rate 

would dip below 5 mL min–1, which was too low for the flow controllers; at these ratios, the fuel 

would be increased, instead, to keep the O flow rate at acceptable levels for the flow controllers. 

The nitrogen flow rate was adjusted for each O flow rate to ensure the total volumetric flow rate 

of gas remained the same. This guaranteed that the contact time inside the reactor remained the 

same, within 5 ms, while the equivalence ratio was varied. The contact times are calculated at 

the catalyst backface temperature. 

Fuel conversion was observed using syringe samples of the effluent gas in a separate GC with an 

Innowax column, a flame ionization detector (FID) (Agilent 6890). The column was set to 

detect acetaldehyde, acetone, methanol, 2-butanone, 1 or 2 butanol, and isobutanol. Water was 

not detected using GC, but calculated using an O species balance of the compounds detected that 

contain O: 

water in microGC

 OOOO FIDGC

. (2) 

Conversion was defined as the amount of isobutanol in the effluent gas compared to the initial 

amount entering the reactor. Thus, if no peak appeared at the retention time of isobutanol for a 

GC sample that was taken, the conversion was considered 100%. Species selectivity can be used 

as a metric of how complete the combustion process is, meaning how much CO2 and H2O are 

formed compared to the stoichiometric amounts. Carbon selectivity was defined as the number 

of carbon atoms in a particular species, divided by the total number of carbon atoms in the 

product gas as shown: 





C in product

C in XSpecies

atomC ySelectivit

#

(3) 

Thus, if the carbon selectivity of CO2 is 100%, complete combustion has occurred. Similarly, H 

selectivity was defined as the number of H atoms in a particular species divided by the total 

number of H atoms in the product gas. This represents the percentage of converted H atoms in 

each of the species studied and is analogous to equation 3 if H is substituted for carbon. 
5

3. Results 

Catalytic partial oxidation of isobutanol was studied using the catalyst that did not contain Rh. 

The reactor was operated at three contact times—25, 56, and 125 ms—at ignition backface 

temperatures of 460, 420, and 290 °C, respectively. The results using the alumina catalyst are 

shown in figure 2. For all three contact times, the vast majority of products were olefins and 

water. H is formed, but at small amounts. The largest selectivity value using the alumina 

catalyst was at a contact time of 125 ms and a  = 6.3377, with a value of 1.59%. 

The H selectivity using the Rh catalyst at each contact time is given in figure 3, with similar 

ignition backface temperatures as previously stated. For all contact times, fuel lean conditions 

exhibit complete combustion when using a Rh catalyst. Fuel rich conditions cause syngas (H2

and CO) and residual hydrocarbons to appear in the exhaust gas. H2 selectivity has a maximum 

point in each contact time, whereas olefin production increases with increasing equivalence ratio. 

The major product within the olefin category was isobutylene. Trace amounts of paraffins are 

found in all cases, usually in the form of methane and propane. For the 25 ms contact time, the 

maximum selectivity to H2 was at  = 3.501 with a value of 52.15%. At the other two times, 56 

and 125 ms, the maximums were observed at  = 1.4248, with values of 62.92% and 24.65%, 

respectively. The production of H as a ratio of fuel input at all contact times and equivalence 

ratios tested using the Rh catalyst is provided in figure 4. The maximum is 995 sccm H2 per 

sccm of isobutanol. 

The temperature of the catalyst, more specifically, its backface in the flow field, was recorded for 

each test. Figure 5 presents the final catalyst backface temperatures as a function of the 

equivalence ratio, for the contact time of 25 ms. The other two contact times show a similar 

trend. The alumina catalyst fluctuates little in temperature, whereas the Rh catalyst operates at 

higher temperatures in fuel lean conditions. The fuel rich temperatures for both catalysts 

generally do not show an increase from the baseline temperature, which is the temperature before 

the fuel is initiated. 

The conversion of isobutanol to other compounds is also shown in figure 5. With a Rh catalyst, 

no remaining isobutanol was detected at lower equivalence ratios. Increasing amounts of 

isobutanol were observed at higher  values. The alumina catalyst does not show a particular 

trend; however, isobutanol was detected at all equivalence ratios tested. With both catalysts, the 

conversion of isobutanol to some other product appears to be high (above 99%). 
6

Figure 2. Hydrogen selectivity of the reactor products for a contact time of (a) 70, ( b) 135, and 

(c) 270 ms using the alumina catalyst (i.e., without rhodium).
7

Figure 3. Hydrogen selectivity of the reactor products for a contact time of (a) 70, (b) 135, and 

(c) 270 ms using the rhodium catalyst. 
8

Figure 4. A H2 produced per amount of isobutanol at various contact times and equivalence ratios. 

Figure 5. Temperatures recorded at the backface of the catalyst are given with solid lines. Dashed 

lines represent isobutanol conversion to other species. Contact time: 70 ms. 
9

4. Discussion 

4.1 Reaction Pathway 

Figures 2 and 3 offer excellent insight into the reaction pathway taken in isobutanol catalytic 

combustion. Although other pathways may be present, the following proposed pathway is 

consistent with the experimental results. The first step is known as dehydration of the 

isubutanol, forming olefins and water: 

iso-C4H9OH  C4H8 + H2O (4) 

This reaction is consistent with the study of 2-butanol decomposition (12), because the operating 

temperatures were always above 275 °C. The following steps are taken to complete combustion 

and require O to do so. 

Partial oxidation of olefins: 

C4H8 + 2 O2  4 CO + 4 H2 (5) 

Oxidation of H2: 

H2 + 0.5 O2  H2O (6) 

Oxidation of CO: 

CO + 0.5 O2  CO2 (7) 

Consider the selectivities of catalytic partial oxidation of isobutanol using the alumina catalyst 

(figure 2) in the fuel lean region ( < 1). The selectivity of water is higher than olefins, implying 

that much of the fuel is completely combusted. Some olefins remain, however, meaning that not 

all the olefins are partially oxidized. As the equivalence ratio increases to the mid range region 

( = 1.4248), the longer contact time is required to progress to combustion. The shorter two 

contact times (25 ms, 56 ms) limit the reactions in equations 5–7. In the higher  range, even the 

longest contact time (125 ms) is not slow enough, such that only half the H atoms are converted 

to water, while the other half are in the form of olefins due to dehydration from the reaction in 

equation 4. The trend of decreasing water selectivity with equivalence ratio is in part due to the 

decrease in O relative to the fuel, making the oxidation reactions harder to achieve; O was found, 

however, in the product gas in all cases using the alumina catalyst. H and CO were found in 

trace amounts (<1%) at operating condition. This strengthens the argument that catalytic 

combustion of isobutanol on the γ-alumina surface proceeds through the proposed pathway. 

Another pathway could be dehydrogenation of isobutanol: 

iso-C4H9OH  C4H8O + H2 (8) 
10

However, because little, if any, H was observed using the alumina catalyst, dehydrogenation 

does not appear to have taken place. The alumina results also indicate that the reactions of 

equations 4, 6, and 7 occur quickly relative to the reaction in equation 5; when olefins are 

partially oxidized, the syngas is quickly converted to water and CO2. 

From figure 3, fuel lean conditions show only water and CO2 as products when Rh is added to 

the catalyst foam. At lean conditions, decomposition of isobutanol and oxidation of the 

intermediate species (equations 4–7) occur on both the alumina and Rh surfaces, converting the 

fuel into its complete combustion products. It can be assumed that isobutanol decomposition 

also occurs on the Rh surface, as figure 5 shows that Rh gives a slightly higher conversion of 

isobutanol (meaning more is dehydrated in addition to the amount converted by alumina). Since 

the difference in conversion values is very small, most of the dehydration of isobutanol can be 

attributed to the alumina. This coincides with the recent literature study on 2-butanol 

decomposition (12), in which the authors concluded that the active sites were on the zirconia 

support of the Pt/ZrO2 catalyst for dehydration. 

While the higher temperatures may cause deactivation for decomposition, Rh does not show 

decreased performance in oxidation. The Rh expedites the conversion process so that complete 

combustion does occur for fuel lean conditions at all three contact times. The olefins blocking 

the sites may be attributed to the change, since they would be in a favorable position for catalytic 

oxidation with the Rh. Moving to a higher equivalence ratio of  = 1.4248 produces H2 for all 

contact times. The decrease in O when increasing the ratio means that the syngas oxidation 

reactions (equation 6 and 7) have less O to use, and cannot fully convert the CO and H2 into CO2

and water, respectively. These steps suffer because the preliminary reaction, partial oxidation of 

the olefins on both surfaces, consumes most if not all the O. 

The differences in magnitude of the H2 selectivities in the presence of Rh for the three contact 

times explain the distribution of O, as well. First, it should be noted that unlike the alumina 

catalyst, no O was observed in the effluent gas. From the alumina catalyst, it is found that 

oxidation on the alumina surface is more favorable with a longer contact time, and that oxidation 

of H2 (or CO) will happen if the olefins are partially oxidized, regardless of the equivalence ratio, 

leaving only a small amount of H2. Since the H2 value in figure 3b is higher than that of figure 

3a, it is reasonable to assume that partial oxidation of olefins on the Rh surface also occurs more 

frequently with longer contact times. Because more O is being used in the partial oxidation of 

olefins, less O is available for the oxidation of syngas on the Rh surface. Thus, at a contact time 

of 56 ms, less of the H2 produced from partial oxidation on the Rh surface is further converted 

than with the shorter contact time. This would also be the case with the longer time (125 ms), 

except that now the alumina in the catalyst is in the combustion dominant regime. At this higher 

contact time, oxidation on the alumina surface takes a more dominant role in converting the 

olefins to water and CO2. 
11

Figure 3a shows a different trend in H2 selectivity than the figures 3b and 3c. The maximum is 

attained at an equivalence ratio of 3.501. With the decrease in O to the new ratio, partial 

oxidation of the olefins on the Rh surface is still occurring, perhaps at the same rate, while 

reactions on the alumina surface and syngas oxidation on the Rh surface are less frequent. At the 

other contact times, the H2 selectivity has decreased, meaning that the Rh surface reaction of 

equation 5 has been reduced with the others. This scenario implies that the Rh at smaller contact 

times is more effective than alumina at activating O2 for surface reactions with olefins, but also 

that this characteristic diminishes with increasing contact time. The rest of the data past this 

equivalence ratio provides the following insight: as the equivalence ratio increases, less O is 

available, lowering the rates of oxidation on both alumina and Rh surfaces. This means that only 

dehydration will occur at even larger  values. Only alumina surface reactions increase in 

occurrence at high  values when the contact time is increased. Contact times larger than those 

investigated here could potentially render the Rh useless; however, such contact times would not 

yield H for fuel cell applications. 

4.2 Hydrogen Production 

From figure 4, it is clear that for maximum yield a contact time of 56 ms with an equivalence 

ratio around 1.4248 is desirable. At the fuel flow rate used for experimentation, 1.012 mL/hr 

(about 8.25 W thermal), the reactor provided at this operating condition the equivalent of 3.61 W 

of H2. This translates to a reformer efficiency of approximately 44%. Even the next higher 

equivalence ratio achieves a higher H yield than the highest peak of the 25 ms contact time, 

being 651 and 550 sccm H2/sccm isobutanol, respectively. This implies there is an optimal 

contact time for H production with this catalyst, not just an optimal equivalence ratio. The 

optimal contact time and equivalence ratio associated with it will be the topic of future research. 

4.3 Temperature Profile 

The temperature profiles portrayed in figure 5 concur with the reaction products of the reactor. 

Because the reactor is adiabatic, all energy entering the system with the reactants also leaves the 

system with the products. In this scenario, the enthalpy released when combusting the fuel is 

distributed through the products, which is observed in the form of a temperature increase. A 

combustion process that sees more than the complete products, CO2 and H2O, is using energy to 

form and sustain those byproducts. Thus, less of a temperature increase will be observed. This 

is the case with the alumina catalyst at all equivalence ratios tested, and the Rh catalyst at fuel 

rich conditions. 
12

5. Conclusions 

The energy-dense, renewable alcohol isobutanol can be reformed using catalytic combustion to 

produce H for use in small power applications such as PEM fuel cells. H production requires Rh 

when using a monolith foam coated with γ-Alumina. This is because the Rh accelerates the 

process that decomposes olefins into H2 and CO. The highest H selectivity observed was 

62.92% at an equivalence ratio of 1.4248 and a contact time of 56 ms. This operating condition 

provided 3.61 W of H2, achieving an approximate reformer efficiency of 44%. Conversion of 

isobutanol to other species was found to be above 99%. 
13

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14

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FT BELVOIR VA 22060-6218 

1 CD OFC OF THE SECY OF DEFNS 

ATTN ODDRE (R&AT) 

THE PENTAGON 

WASHINGTON DC 20301-3080 

1 US ARMY RSRCH DEV AND ENGRG CMND 

ARMAMENT RSRCH DEV & ENGRG CTR 

ARMAMENT ENGRG & TECHNLGY CTR 

ATTN AMSRD AAR AEF T J MATTS 

BLDG 305 

ABERDEEN PROVING GROUND MD 21005-5001 

1 US ARMY INFO SYS ENGRG CMND 

ATTN AMSEL IE TD A RIVERA 

FT HUACHUCA AZ 85613-5300

1 COMMANDER 

US ARMY RDECOM 

ATTN AMSRD AMR W C MCCORKLE 

5400 FOWLER RD 

REDSTONE ARSENAL AL 35898-5000

1 US GOVERNMENT PRINT OFF 

DEPOSITORY RECEIVING SECTION 

ATTN MAIL STOP IDAD J TATE 

732 NORTH CAPITOL ST NW

WASHINGTON DC 20402 

8 HCS US ARMY RSRCH LAB 

1 ELEC ATTN IMNE ALC HRR MAIL & RECORDS MGMT 

ATTN RDRL CIO LL TECHL LIB 

ATTN RDRL CIO MT TECHL PUB 

ATTN RDRL SED E A GAMSON 

ATTN RDRL SED E I LEE (3 HC AND 1 ELEC) 

ATTN RDRL SED P J ST CLAIR 

ADELPHI MD 20783-1197 

TOTAL: 15 (12 HCS, 1 CD, 2 ELEC)