Preparation and characterisation of amorphous mesoporous aluminophosphate and metal aluminophosphate as an efficient heterogeneous catalyst for transesterification reaction

Article abstract of DOI:10.1016/j.crci.2011.09.013

Preparation, characterisation of pure aluminophosphate and aluminophosphate modified with different transition metals (V, Fe, Co Ni & Cu) and their catalytic activity in mono/dibenzyl substituted malonates synthesis are explained. The materials were prepared by the coprecipitation method in the absence of any structure-directing species and characterized for their composition, crystalline nature, total surface acidity, specific surface area pore diameter and pore volume by different techniques. Catalytic activity of the materials was investigated in transesterification of diethylmalonate with benzyl alcohol in liquid phase. Pure aluminophosphate resulted only in benzyl ethylmalonate whereas the incorporation of transition metals favored the formation of both benzyl ethylmalonate and dibenzylmalonate. Catalytic activity parallels the surface acidity and mesoporosity of the catalysts. The effect of the molar ratio of reactants, amount of catalyst, and reaction time on the conversion of diethyl malonate and transester yield has been studied. The highest activity of iron aluminophosphate is attributed to its mesoporous nature with uniform pore size distribution, higher surface acidity and surface area. Further, the scope and generality of iron aluminophosphate as a catalyst in the transesterification was studied using various aliphatic, alicyclic and aromatic alcohols. The catalysts could be recycled by retaining most of its initial activity.

Full text of DOI:10.1016/j.crci.2011.09.013

C. R. Chimie 14 (2011) 1109–1116
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´
Full paper/Memoire
Preparation and characterisation of amorphous mesoporous
aluminophosphate and metal aluminophosphate as an efficient
heterogeneous catalyst for transesterification reaction
A.V. Vijayasankar a,b, N. Nagaraju b,
*
a Department of Engineering Chemistry, Christ University, Hosur Road, Bangalore 560029, India
b Catalysis Research Laboratory, St. Joseph’s College Research Centre, 36, Lalbagh Road, Shanthi Nagar, Bangalore 560 027, India
A B S T R A C T
A R T I C L E I N F O
Preparation, characterisation of pure aluminophosphate and aluminophosphate modified
with different transition metals (V, Fe, Co Ni & Cu) and their catalytic activity in mono/
dibenzyl substituted malonates synthesis are explained. The materials were prepared by
the coprecipitation method in the absence of any structure-directing species and
characterized for their composition, crystalline nature, total surface acidity, specific
surface area pore diameter and pore volume by different techniques. Catalytic activity of
the materials was investigated in transesterification of diethylmalonate with benzyl
alcohol in liquid phase. Pure aluminophosphate resulted only in benzyl ethylmalonate
whereas the incorporation of transition metals favored the formation of both benzyl
ethylmalonate and dibenzylmalonate. Catalytic activity parallels the surface acidity and
mesoporosity of the catalysts. The effect of the molar ratio of reactants, amount of catalyst,
and reaction time on the conversion of diethyl malonate and transester yield has been
studied. The highest activity of iron aluminophosphate is attributed to its mesoporous
nature with uniform pore size distribution, higher surface acidity and surface area.
Article history:
Received 19 July 2011
Accepted after revision 27 September 2011
Available online 8 November 2011
Keywords:
Heterogeneous catalysis
Amorphous materials
Mesoporous materials
Transesterification
Biaryls
Supported catalysts
Green chemistry
Further, the scope and generality of iron aluminophosphate as
a catalyst in the
transesterification was studied using various aliphatic, alicyclic and aromatic alcohols. The
catalysts could be recycled by retaining most of its initial activity.
ß 2011 Acade´mie des sciences. Published by Elsevier Masson SAS. All rights reserved.
1. Introduction
not only the protocols reported by transesterification are
time consuming but also the catalysts used are toxic,
Transesterification is one of the classic organic reac-
tions that have enjoyed numerous laboratory uses and
industrial applications. Organic chemists make use of this
reaction quite often as a convenient means to prepare
esters. In general, transesterification reactions can be
accelerated by both acids and bases, in either homoge-
neous or heterogeneous conditions; they can also occur
under neutral conditions [1]. Thus, a number of procedures
for transesterification have been reported, which are
catalyzed by traditional acids, organic bases. However,
corrosive, expensive and produce large amounts of
byproducts which are difficult to separate from the
reaction mixture. In view of environment and economical
concern, it is still remarkable to design a catalyst which is
easily separable from the products, less toxic and reusable.
Malonic esters are known for their importance either as
starting materials or intermediates in organic fine chemi-
cals synthesis [2,3]. Generally the synthesis of benzyl
malonate is associated with the use of either toxic or
lachrymetric reagents under homogenous conditions. The
synthesis of substituted malonates via transesterification
reaction in the presence of heterogeneous catalysts has
been found to be a better route than the conventional
methods. However, not only the protocols followed here
* Corresponding author.
E-mail address: nagarajun@yahoo.com (N. Nagaraju).
1631-0748/$ – see front matter ß 2011 Acade´mie des sciences. Published by Elsevier Masson SAS. All rights reserved.
doi:10.1016/j.crci.2011.09.013

1110
A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
were time consuming but also the catalysts used were
toxic or expensive [4,5]. Further, the synthesis of bulky
dibenzyl malonate (DBM) via transesterification is found
to be challenging due to porous diffusional limitations of
the heterogeneous catalysts.
Aluminophosphate (ALP) and metal aluminopho-
sphates (MALP) are well known for their applications as
heterogenous catalysts in organic fine chemical synthesis
[6]. The catalytic activity of the heterogeneous catalysts
has been found to depend on their pre- and postsynthesis
conditions [7]. There are several attempts made on the
modification of the acid-base properties of ALPs by
incorporation of a transition metal [8,9] to investigate
their influence on the textural properties and catalytic
activity.
As a part of our on-going research, we have reported
[10] the dependence of the structure and catalytic activity
relationship of amorphous MALPs for the synthesis of
biphenyl urea via alkylation. The effect of preparation and
iron loading on the transesterification activity of iron ALPs
were already studied and found that catalyst prepared by
dropwise addition of ammonia with Fe: Al: P (0.025: 0.95:
1) mole ratio exhibited highest activity for the selected
reaction [11].
The main objective of this study was to investigate the
effect of transition metal ions on the textural properties of
modified ALPs and hence on their catalytic activity in the
transesterification of diethyl malonate (DEM) with benzyl
alcohol (BA). Furthermore, the scope, generality and
ecofriendly nature of the iron ALP catalyst are demon-
strated by conducting transesterification of DEM using
various aliphatic, alicyclic and aromatic alcohols. Optimi-
zation reactions were also conducted over FeALP in the
same reaction which led us to identify the reaction
conditions for high yield and selectivity for the desired
transesterification products. A possible mechanism of the
catalytic reaction was also proposed.
ray diffraction (PXRD) patterns of the catalysts were
recorded in the range of 2 = 28–708 using an X-pert Pro
u
Philips diffractometer equipped with Ni filtered Cu-K
˚
l = 1.5418 A using a graphite crystal mono-
a
radiation
chromator. FTIR spectra were recorded over a range of
400–4000 cmÀ1 using Philips Nicolet IR 200 instrument
using the KBr pellet technique. The specific surface area,
pore diameter and pore volume were evaluated by NOVA
1000 Quanta chrome high-speed gas sorption analyzer
instrument. In this analysis, the samples were degassed at
523 K for 5 h before measurements. Specific surface area
was calculated using the BET equation. The pore volume
and pore size distributions were estimated at a relative
pressure of 0.94 (p/p0) and N2 adsorption-desorption
isotherms using BJH model respectively. Total surface
acidity by NH3-TPD was determined using Puls Chemi-
sorb 2705 from Micromeritics. Here, 100 mg of fresh
sample was degassed under a helium stream for 1 h,
ammonia (99.99%) gas was injected into the stream until
saturation was reached, cooled to 323 K. The system was
maintained at 323 K for 30 min. After purging, the system
with flowing helium for 2 h at 323 K, the sample
was heated at the rate of 5 K minÀ1 in helium to 973 K.
The change in concentration of the desorbed NH3
was monitored using an online thermal conductivity
detector.
2.3. Catalytic activity
The catalytic activity of ALP and MALP was studied in
liquid phase transesterification reaction of DEM with BA
(Scheme 1). In a typical reaction, a mixture of 0.5 g of the
catalyst, 5 mmol of DEM and 15 mmol of BA was taken in a
100 ml RB flask fitted with water-cooled condenser and
heated in temperature controlled oil bath. The reaction
mixture was stirred magnetically at 110 8C for 4 h.
Aliquots of the reaction mixture were periodically
withdrawn and subjected to gas chromatographic analy-
sis. After the stipulated time, the reaction mixture was
cooled to room temperature and centrifuged to separate
the solid catalyst. The components in the filtrate were
analyzed by GC-MS.
2. Experimental
2.1. Preparation of the catalysts
MALPs (M = V, Fe, Co, Ni and Cu) were prepared by a
simple precipitation method in the absence of templates.
Aluminum nitrate, the transition metal salt and orthopho-
sphoric acid in the molar ratio 0.95 (Al): 0.025 (M): 1 (P)
were dissolved in 500 cm3 deionised water and stirred
mechanically for 1 h at 60 8C. Aqueous ammonia (28%) was
added drop wise at a rate of 0.5 ml/min from a microbur-
ette until the pH of the solution rose to 9. The precipitate
obtained was filtered, washed several times with deionised
water to remove the soluble impurities. The solid obtained
was dried at 120 8C for 12 h and calcined at 550 8C for 5 h.
The same method was followed but in the absence of
transition metal salt to prepare pure ALPs.
3. Results and discussion
3.1. Composition and surface area
The abbreviations used and the physico-chemical
properties of the catalysts are given in Table 1. The
percentage composition of the metal, aluminium and
phosphorous in the catalyst were found to be in the
expected range according to the formula; M0.025 Al0.95 P1.
The specific surface area of pure ALP was lower than the
MALP, indicating the influence of transition metal on the
textural properties of ALP. The increase in surface area can
be explained as follows: the strong interaction of metal in
the form of oxide or phosphate with the ALP reduces the
surface diffusion of ALP and inhibits the sintering of the
material. The maximum surface area was exhibited by the
FeALP (181 m2/g) materials compared to other catalysts
used.
2.2. Characterization of catalysts
The percentage composition of the transition metal,
aluminum and phosphorous in the catalyst was deter-
mined by spectrophotometric methods [12]. Powder X-

A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
1111
Scheme 1. Transesterification of diethyl malonate with benzyl alcohol.
Table 1
Physico-chemical properties of metal aluminophosphates (MALP) catalysts.
Sl No
Catalyst
Surface area (m2/g)
Total acidity NH3-TPDa
Pore diameter (nm)
Total pore volume (cm3/g)
1.
2
3
4
5
6
FeALP
CoALP
CuALP
NiALP
VALP
ALP
181.4
125.1
84.51
171.0
110.3
78.6
12.058
10.786
8.401
7.395
7.386
6.723
7.98
14.5
11.9
9.84
12.3
5.48
0.362
0.456
0.252
0.407
0.426
0.107
a
mg of NH3/g of catalyst.
3.2. Powder X-ray diffraction
3.3. FTIR spectra
The PXRD patterns of ALP and MALP calcined at 550 8C
are given in Fig. 1. All the samples except FeALP exhibited a
The FTIR spectra of ALP and MALP are given in the Fig. 2.
A broad absorption band in the range 3430–3448 cmÀ1 is
attributed to the surface hydroxyl groups, which may be
associated with transition metal, aluminum and phospho-
rous atoms [14]. The intensity of the band is significantly
higher in the case of MALP’s compared to ALP. Broad and
weak absorption bands around 1623–1640 cmÀ1, especial-
ly in the case of MALP’s indicated the presence of adsorbed
water molecule. The broad and strong bands in the range
1100–1128 cmÀ1 exhibited by all the samples is due to the
asymmetric vibration of phosphate (triply degenerate P–O
broad band in the range 2u = 158–308 range. This feature of
PXRD is characteristic of amorphous ALPs [13]. FeALP
exhibited sharp diffraction peaks at d = 3.8 (2u = 23.38), 3.3
˚
(2
u
= 26.998) and 2.3 A (2
u
= 38.58), indicating the presence
of an iron aluminum phosphate phase [JCPDS File No.:
210006]. It is an indication of the intervention of iron
species in the formation of amorphous aluminum phos-
phate. Thus, PXRD pattern clearly revealed the amorphous
nature and low degree of crystallinity of the materials.
Fig. 1. Powder X-ray diffraction (PXRD) patterns of aluminophosphate (ALP) and metal aluminophosphates (MALP) catalysts.

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A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
Fig. 2. FTIR Spectra of aluminophosphate (ALP) and metal aluminophosphates (MALP) catalysts.
stretching vibration) [15]. The peak centered at 478–
490 cmÀ1 is assigned to the triply degenerate bending
vibration of O–P–O bond in pyrophosphates. All the
samples except NiALP and CuALP exhibited absorption
at 691 cmÀ1 due to stretching vibrations of Al–O and P–O
bonds [16]. It is also noteworthy that the bending vibration
of the hydroxyl groups and the phosphate groups assigned
in the range as indicated above were sensitive to the nature
of the transition metal. The centre of these bands has been
shifted to the lower wave number with increase in the
atomic number of the metal. Thus, FTIR studies indicated
clearly the presence of surface hydroxyl groups and the
phosphate moiety in ALP and MALP’s.
3.5. NH3–TPD studies
The concentration and strength of the surface acid sites
on ALP and MALP were determined by NH3–TPD method.
The total acidity in terms of mg of NH3 per g of the catalyst is
presented in Table 1. All the samples were found to possess
weak to moderate strength acid sites. The surface acidity is
attributed to the presence of Al–OH and P–OH groups in
amorphous matrix. In the case of ALP, complete desorption
of ammonia occurred below 100 8C indicating the presence
of only very weak acid sites [19]. However, desorption of
ammonia from MALP occurred in the temperature range
180–300 8C. This showed the presence of stronger acid sites
on MALP compared to ALP. Further the broad temperature
range (180–300 8C) of desorption of ammonia revealed that
the surface acid strength is widely distributed. In the case of
FeALP, the NH3– TPD profiles were broader and occurred at
higher temperature regions. It is a clear indication that the
acid sites concentration as well the strength was higher on
FeALP compared to other MALP’s [20].
3.4. N2 adsorption–desorption isotherms
The adsorption–desorption isotherms of ALP and MALP
were nearly the same, and belonged to type IV category
(Fig. 3) indicating the mesoporous nature of the materials
[17]. Further except FeALP, all other materials exhibited H1
type hysteresis loops indicating difference in the type of
pores. The nitrogen adsorption–desorption isotherms of
FeALP exhibited H2 loop. The appearance of H2 hysteresis
loop between the 0.4–0.7 indicated the condensation and
evaporation of adsorptive liquid occurring from the pores
with narrow necks and wide bodies referred to as ‘ink bottle’
pores [18]. The steep rise in adsorbed volume of nitrogen at
p/p0 > 0.4 represented narrow pore size distribution in
FeALP. These observations indicated efficient adsorptive
capacity of FeALP as well as significant difference in its
textural properties compared to other MALP’s.
Thus PXRD, FTIR, BET surface area, N2 sorption and NH3
TPD studies indicated that the textural properties of ALP
were modified by incorporation of transition metal ions
and FeALP sample was distinctly different from other
MALP’s in its textural properties.
3.6. Catalytic activity studies
The catalytic activity of ALP and MALP’s was investi-
gated in the transesterification reaction between BA and
DEM. The bulky reactant molecules were consciously

A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
1113
Fig. 3. Nitrogen adsorption–desorption isotherms of aluminophosphate (ALP) and metal aluminophosphates (MALP).
chosen to derive information on the effect of textural
properties mainly pore size of the amorphous MALP’s on
their catalytic activity.
indicated by NH3-TPD studies. The yield and selectivity of
the transester products altered with the variation in
density and strength of the acid sites.
The transesterification activity of ALP and MALP’s in
terms of the percentage conversion of DEM into benzyl
malonates along with the selectivity towards the mono-
and dibenzyl transester products are given in the Table 2.
The catalytic activity of the materials was in accordance
with the increasing order of their total surface acidity as
Pure ALP favored the formation of only benzylethyl
malonate (BEM). NH3-TPD studies on this material
revealed the presence of only weak acid sites on its
surface. Hence acid sites with weak strength associated
with the surface hydroxyl groups are the active centres for
the formation of BEM. MALP, on the other hand, favored
Table 2
Transesterification activity of aluminophosphate (ALP) and metal aluminophosphates (MALP) in the reaction between diethyl malonate (DEM) and benzyl
alcohol (BA).
Sl No:
Catalyst
Conversion of DEM (%)
Selectivity for BEM (%)
Selectivity for DBM (%)
1
2
3
4
5
6
FeALP
CoALP
CuALP
NiALP
VALP
ALP
87.7
74.9
45.2
40.3
40.1
35
49.4
33.8
43.1
57.7
50.9
100
50.6
66.2
56.9
42.3
49.1
0
DBM: dibenzyl malonate; Reaction conditions DEM = 0.05 mol, BA = 0.15 mol, amount of catalyst = 0.1 g, reaction time = 4 h.

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A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
the formation of both BEM and DBM. Thus the transition
metal ions are the catalytically active centres that are
responsible for the formation of DBM. This aspect is further
clear from the fact that the pure ALP and V, Ni, Cu
containing MALP’s possessed comparable surface acidity
but only transition metal containing samples exhibited
activity towards the formation of DBM. Further Fe and Co
containing ALP exhibited significantly higher activity for
DBM formation. This is due to their higher total surface
acidity compared to other transition metal containing ALP.
It is further interesting to note that FeALP exhibited higher
total transester yield compared to CoALP. This difference in
catalytic activity may be attributed to the difference in the
pore structure between these samples.
FeALP, as indicated by sorption studies, had pores of
regular size with diameter in the mesopores range and
uniformly distributed through out the sample, which could
overcome the porous diffusional constraints and enable
the molecules to access all the active sites of acidic nature
and hence higher catalytic activity. CoALP and other
MALP’s exhibited higher average pore diameter value than
FeALP, due to large number of irregular pores with smaller
diameter. Thus, from these observations, it may be inferred
that not only total acid strength but also the textural
properties of MALP were responsible for the formation of
DBM.
Fig. 4. The effect of molar ratio of reactants in the transesterification of
diethyl malonate (DEM) with benzyl alcohol (BA) over FeALP catalyst.
However, there was a significant increase in the conversion
to 79%, when the amount of the catalyst was increased to
0.1 g. Further, increase in the amount of the catalyst up to
0.5 g, did not show any significant change. Thus 0.1 g
seems to be an optimum amount of the catalyst to get a
good exposure of the reactants to the catalytically active
sites and hence obtain products in good yield.
3.7. Optimisation reactions
As FeALP exhibited the highest conversion of DEM and
also retained its activity for a longer duration of reaction,
further optimization reactions were carried out in pres-
ence of this catalyst by varying the molar ratio of the
reactants, amount of the catalyst and duration of the
reaction.
3.7.3. The effect of duration of the reaction
The transesterification reaction was monitored by
changing the duration of the reaction. With increase in
time the amount of BEM increased up to 4 h then
decreased. However, the amount of DBM increased
throughout the reaction (Fig. 6). This may be accounted
for the disproportionation of initially formed BEM into
DBM according to Scheme 3. For the disproportionation
reaction to occur, it appears that there is a need of a
minimum concentration of BEM, hence the decrease in
concentration of BEM is more significant only after 4 h.
This aspect is further confirmed by the fact that the
percentage conversion of DEM (Fig. 7) almost remained
constant after 4 h.
3.7.1. The effect of molar ratio
An increase in BA content in the reaction mixture
increased the percentage yield of DBM with a correspond-
ing decrease in the yield of BEM (Fig. 4). We propose that
BEM formed in the first step may further react with excess
of BA increasing the amount of DBM (Scheme 2). It is also
noteworthy that the total percentage yield of transester
products increases with increase in alcohol content. The
maximum yield of transester products was obtained when
the DEM: BA ratio was 1:3.
4. Scope and generality of the catalyst
3.7.2. The effect of catalyst amount
The scope and versatility of the FeALP as a catalyst in
the transesterification is examined by further conducting
the reaction between DEM with different alcohols under
It is clear from the Fig. 5, that the conversion of DEM
was only 65.6% when the amount of catalyst was 0.05 g.
Scheme 2. Transesterification in two steps in excess of benzyl alcohol (BA).

A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
1115
Fig. 5. The effect of the amount of FeALP in the transesterification of
Fig. 7. The effect of the reaction time in the conversion of diethyl
malonate (DEM) over FeALP in the transesterification of diethyl malonate
(DEM) with benzyl alcohol (BA).
diethyl malonate (DEM) with benzyl alcohol (BA).
Table 3
Transesterification of diethyl malonate (DEM) with different alcohols
over FeALP catalyst.
Entry
Alcohol
DEM
Product
selectivity
(%)
conversion %
A
B
1
n-propanol
83.2
91.3
87.0
94.1
96.5
98.7
100
100
85.7
67
32.3
48.8
55.3
17.4
12.1
15.4
27.4
14.3
15.2
42.2
47.4
15.2
15.2
67.7
51.2
44.7
82.6
87.9
84.6
72.6
85.7
84.8
35.8
31.6
84.8
84.8
2
n-butanol
2
2-butanol
3
n-hexanol
4
n-heptanol
5
n-octanol
6
Cyclohexanol
o-Cresol
7
8
Benzyl alcohol
Amino benzyl alcohol
Hydroxyl benzyl alcohol
Benzyl alcohol (RI)
Benzyl alcohol (RII)
9
10
11
12
78
82
80
A: monoalkyl/aryl substituted malonate: B: dialkyl/aryl substituted
malonate; reaction conditions; catalyst (FeALP) = 0.1 g, DEM, 5 mmol;
alcohol, 15 mmol; temperature = 383 K run time = 4 h; RI: recycled I, RII:
recycled II.
Fig. 6. The effect of reaction time in the selectivity of benzylethyl
malonate (BEM) & DBM over FeALP catalyst.
the optimized reaction conditions. The results are pre-
sented in the Table 3. It is noticed that the transesterifica-
tion of DEM could be performed with various aliphatic and
aromatic alcohols with high efficiency over FeALP catalyst.
The percentage conversion of DEM was higher in the case
of aliphatic and alicyclic alcohols than with aromatic
alcohols. The DEM conversion increased with increase in
aliphatic chain length form n-propanol to n-octanol (Table
2, entry 1–5). This may be due to the ease with which the
alkoxy group of alcohol generated becomes more facile
with increase in the chain length of the aliphatic alcohol,
which decreases the electron releasing property of an alkyl
group. The generation of alkoxy group is further facilitated
by the acid sites of the catalyst.
Though in the present studies, the percentage conver-
sion of DEM with BA was low, (Table 3, entry 8) the yield
and selectivity for DBMs was significantly higher com-
pared to the catalysts reported in the literature [3,4,21].
Substituted BAs (Table 3, entries 9, 10) showed very low
Scheme 3. Disproportionation of monoester to diester.

1116
A.V. Vijayasankar, N. Nagaraju / C. R. Chimie 14 (2011) 1109–1116
conversion and selectivity for DBMs. Thus the conversion
of DEM and the product selectivity (monoester/diester)
depended on the structural properties of the alcohol and
total acidity and pore structure of the catalysts. The
reusability of the catalyst was also investigated in the
reaction of DEM with BA and found to be recyclable
without loss of its activity for at least two cycles. (Table 3,
entries 11 and 12).
It is noteworthy from the reported literature that
several attempts have been made to synthesize diaryl
malonate using different catalysts. However, the duration
of reaction, preparation, cost and recyclability of the
catalyst, selectivity of the products were not advantageous.
In this report, we have demonstrated that dialkyl as well as
diaryl malonates can be synthesised with high yield in
short duration using FeALP catalyst prepared by a simple
precipitation method.
Acknowledgment
We thank the Material Research Group, St Joseph’s
College Research Centre, Bangalore for powder XRD
analysis and Bangalore Institute of Technology, Bangalore
for providing the BET surface area analysis facilities. We
thank Mr. C.U. Anis, SUD-CHEMIE, Cochin for the NH3-TPD
analysis. We also thank UGC, New Delhi for providing
financial assistance for a minor research project.
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