CO2 solubility and liquid phase ion speciation determined by C NMR13 technique in IPAB-CO2-H2O system

International Journal of Greenhouse Gas Control 50 (2016) 190–197

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CO2 solubility and liquid phase ion speciation determined by 13 C NMR technique in IPAB-CO2 -H2 O system Bin Liu, Xiao Luo, Wichitpan Rongwong, Raphael Idem, Zhiwu Liang ∗ Joint International Center for CO2 Capture and Storage (iCCS), Provincial Hunan Key Laboratory for Cost-effective Utilization of Fossil Fuel Aimed at Reducing CO2 Emissions, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China

a r t i c l e

i n f o

Article history: Received 23 March 2016 Received in revised form 21 April 2016 Accepted 25 April 2016 Keywords: Quantification Carbon dioxide Absorption 13 C NMR

a b s t r a c t A newly developed alkanolamine (4-isopropylamino-2-butanol (IPAB)), with a high carbon dioxide (CO2 ) loading capacity and low regeneration energy, as a potential CO2 absorbent was studied in this work. The accurate quantitative 13 C NMR techniques were selected to investigate the ion speciations in aqueous IPAB-CO2 -H2 O system. Calibration equations were established to quantify the exact ion concentrations of free amines and protonated amines in the IPAB-CO2 -H2 O system. The results show that the NMR method can be used to obtain both qualitative and quantitative information of the amine-CO2 -H2 O system. IPAB had a larger capacity for CO2 than MEA because of the dominant formation of bicarbonate rather than carbamate. No significant carbon peak of carbamate was observed at various CO2 loadings in the IPAB solutions, which can be explained by the sterically hindered effects on the forming of an unstable carbamate. © 2016 Elsevier Ltd. All rights reserved.

1. Introduction Carbon dioxide (CO2 ) capture using chemical absorption with amines has been studied for decades, but there are a number of drawbacks, such as high energy consumption for CO2 desorption and solvent regeneration, corrosion, and degradation in the presence of acid gases and oxygen (Rochelle, 2009), which are all linked to the ion components of the amine solution. This implies that in order to improve the efficiency of CO2 capture, it is necessary to perform a comprehensive study on the speciation of both conventional and novel solvents. Nuclear magnetic resonance (NMR) technology has been used to investigate the carbamate stability (Ciftja et al., 2011), and qualitative or quantitative analyses of all the ions existing in the liquid solution (Hartono et al., 2007; Jakobsen et al., 2005; Fan et al., 2009). This makes NMR a very effective tool in the development of vapor–liquid equilibrium (VLE) model and the study of kinetics of CO2 absorption. Consequently, ion speciation determination using NMR techniques can essentially contribute to a better understanding of the behavior of CO2 absorption into amine solutions. The NMR techniques have been applied for the detection of ions species in amine-CO2 -H2 O solutions in the fieldof CO2

∗ Corresponding author. E-mail address: [email protected] (Z. Liang). http://dx.doi.org/10.1016/j.ijggc.2016.04.027 1750-5836/© 2016 Elsevier Ltd. All rights reserved.

capture to establish or develop VLE models, as recently reviewed in detail by Shi et al. (2012a) and Perinu et al. (2014). The 13 C NMR calibration equations, a convenient method proposed by Shi et al. (2012b), were used for identifying the exact amounts of the free amine (DEAB) and protonated amine (DEABH+ ) in the DEAB-CO2 H2 O system, which was shown to be accurate and convenient. With this method, it is possible to directly analyze the amounts of the main ion species of amine-CO2 -H2 O system and establish its VLE model. 4-Isopropylamino-2-butanol (IPAB, Fig. 1b) is considered to be a secondary amine with a higher CO2 absorption rate than DEAB (Fig. 1a). It has been shown that IPAB in comparison with 2-amino2-methyl-1-propanol (AMP), methyldiethanol-amine (MDEA), monoethanolamine (MEA) and diethanolamine (DEA) has excellent performance in the CO2 absorption process, a high CO2 absorption and cyclic capacity as DEAB, and lower energy requirement for regeneration, compared with MEA which required a lot of energy to regenerate (Tontiwachwuthikul et al., 2008). In this work, useful information for CO2 solubility in amine-CO2 -H2 O system were provided and the calibration equation for the aqueous IPAB solutions at various CO2 loadings was established by the 13 C NMR techniques. Then, the main ions information in these solutions was also determined and given quantitative information with the established calibration equations. By determining all ion species, it is possible to infer the possible relations between molecular structure of the amines and reaction mechanism in amine-CO2 -H2 O system.

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191

Fig. 1. 3D chemical structure of DEAB and IPAB.

Fig. 2. The 1 H and 13 C NMR spectrum of synthesized IPAB at 293 K.

2. Experimental 2.1. Chemicals CO2 and N2 gases (99.9%, obtained from Fang Gang Gas Co., Changsha, China) were mixed by using a gas mass flow meter (D08-2F, Sevenstar Electronics Co. Ltd, Beijing, China) to simulate flue gas. Isopropylamine, methyldiethan-olamine, methanol, sodium bicarbonate, sodium carbonate deuterium oxide and 1,4dioxane were all purchased from InnoChem Science Technology Co. Ltd (Beijing, China). Deuterium oxide and 1,4-dioxane were used as signal lock and internal standard reference. Methyl vinyl ketone (98%) was purchased from Xishi chemical technology company (Shanghai, China). Isopropylamine-2-butanol (IPAB) and diethylamine-2-butanol (DEAB) were both synthesized in the lab with a high purity measured by using a nuclear magnetic resonance (NMR) instrument (INOVA-400, Varian company, America) and liquid chromatography-ion trap mass spectrometer (LCQ-Advantage, Thermo Finnigan, America). 5 mm NMR tubes produced by Wilmad Lab Glass bought from Synthware glass Co. Ltd (Beijing, China) were used for NMR tests in our experiment. 2.2. Synthesis of new solvents The synthesis process was performed following the procedure in the patent described by Tontiwachwuthikul et al. (2008). The product and its purity were determined by NMR instrument and GC–MS which can be found in our previous work on DEAB (Liu et al., 2014). The 1 H and 13 C NMR spectrum of synthesized IPAB can be found in Fig. 2. 2.3. Chemical reaction The reaction mechanism between carbon dioxide and DEAB (a tertiary amine) was introduced by Shi et al. (2012b) in which

DEAB does not directly react with CO2 but performed as a catalyst for CO2 hydration reaction as shown in Eqs. (1)–(4). IPAB was a secondary amine, and a two step mechanism firstly proposed by Caplow (1968) and reintroduced by Danckwerts (1979) was applied to explain chemical reaction in IPAB-CO2 -H2 O system, as shown in Eqs. (5)–(9). The chemical reactions of CO2 absorption into DEAB can be expressed as: CO2 + H2 O + DEAB ↔ HCO3 − + DEABH+

(1)

+

+

DEAB + H ↔ DEABH

(2)

CO2 + H2 O ↔ H2 CO3 ↔ HCO3 − + H+

(3)

−

HCO3 ↔ CO3

2−

(4)

The chemical reaction of CO2 absorption into IPAB can be expressed as: CO2 + IPAB ↔ IPABH+ COO− +

(5) −

−

IPABH COO + IPAB ↔ IPABCOO + IPABH

+

(6)

IPABH+ COO− + H2 O ↔ IPABH+ + HCO3 −

(7)

CO2 + H2 O ↔ HCO3 − + H+

(8)

−

HCO3 ↔ CO3

2−

+H

+

(9)

According to the chemical reaction mechanism (Eqs. (1)–(9)), the main ion speciations in the liquid phase (amine-CO2 -H2 O system) were free amine, protonation amine, carbamate, carbonate, bicarbonate, as shown in Fig. 3. It has been found that the exact amounts of carbamate, carbonate, and bicarbonate can be determined by the chemical shifts and peak area integral, as shown in Eqs. (10)–(13) proposed by Holmes et al. (1998). The varied chemical shift of HCO3 − and CO3 2− reflects their relative ratios in the solutions. The amounts of protonated amines and free amines were

192

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Fig. 3. Potential ion species in DEAB-H2 O-CO2 system and IPAB-CO2 -H2 O system. Symmetric carbons were marked by dotted ellipse.

determined by the calibration equations of free amine and protonated amine as suggested by Shi et al. (2012b). The loading of CO2 in the solution can be analyzed by titration method (Fu et al., 2015). [NH2 CO2 − ]

=R

(10)

R × [CO2 ]0 1+R

(11)

[HCO3 − ] + [CO3 2− ] [NH2 CO2 − ] = [CO3 2− ] = [HCO3 − ] =

ı − 160.33 × [CO2 ]0 (169.09 − 160.33) × (1 + R) 169.09 − ı × [CO2 ]0 (169.09 − 160.33) × (1 + R)

(12) (13)

were prepared at 1.0 M aqueous solution and analyzed at 293 K on the NMR instrument. Its chemical shifts were 168.151 and 160.793 ppm, respectively, which is very close to the results observed by Holmes et al. (1998) and Shi et al. (2012b). For quantitative analysis of exact components in liquid phase after absorption, the reverse gated decoupling technique was selected in this work to ensure that the effect of Nuclear Overhauser Effect (NOE) had been absent. The 13 C NMR spectra were recorded at 400 MHz with a NMR spectrometer (DRX-500, Varion, Billerica, MA) at 293.15 K. About 10% deuterium oxide was used as signal lock and drops of 1,4-dioxane was used as an internal standard. Delay times between pulses of five to six times the spin-lattice relaxation times were recommended for use for the measurement of the 13 C NMR spectrum (Holmes et al., 1998).

2.4. CO2 absorption 3. Results and discussion CO2 absorption test was conducted by the same apparatus as described in our previous work (Liang et al., 2015). In a typical experiment, CO2 and N2 were mixed for ensuring an accurate CO2 partial pressure and the mixed gas was bubbled into deionized water before being injected into the absorption cell. The same amount of aqueous amine solution was loaded into bubbling cell for absorption and a desired absorption temperature was controlled by a thermostated water bath. The outlet gas was firstly going into a condenser, then dried and detected by CO2 analyzer for determining the amounts of CO2 at different absorption times, as shown in Fig. 4. 2.5.

13 C

NMR determination

For preparation of 13 C NMR samples, solutions at various CO2 loadings were obtained by injecting pure CO2 gas into the aqueous alkanolamine solutions with a certain flow rate at a certain temperature and time. The reference chemicals, Na2 CO3 and NaHCO3 ,

3.1. CO2 absorption To check the reliability of our experimental setup for CO2 solubility in aqueous amine solutions, the solubility of CO2 in 30 wt.% MEA at 313 K and CO2 partial pressures of up to 101.3 kPa was measured and compared with equilibrium data available in the literature, as shown in Table 1. The results show in a reasonable agreement with the data reported by Yamada et al. (2013). The equilibrium solubility and absorption rate of CO2 in 1.5 M aqueous MDEA, DEAB, IPAB are given in Table 2 and Fig. 5, respectively. It can be seen that the CO2 solubility in 1.5 M aqueous IPAB, DEAB, MDEA solutions at 313 K following order: DEAB > IPAB > MDEA at a typical absorption experiment with the CO2 partial pressure range from 15 kPa to 101.3 kPa. The results were determined by the least-squares fit of all data points to the following polynomial equation: ln(p) = A × ˛3 + B × ˛2 + c × ˛ + D where A, B, C, and D are fitting parameters. The values of these

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193

Went to fume hood Gas mixer Flow meter

CO2

Valve T Dry gas

T

Wet CO2+N2

Condenser

T

Temp gauge

Gas disperser

Flow meter

N2

solution

water Saturation

Reactor

T

Heating coil

Water bath Fig. 4. The experimental setup of CO2 absorption by 1.5 M aqueous amines solutions (Liang et al., 2015).

Table 1 The solubility of CO2 in 30 wt.% aqueous MEA solution at 313 K. Yamada et al. (2013)

This work

CO2 loading (mol CO2 /mol amine)

CO2 partial pressure (kPa)

CO2 loading (mol CO2 /mol amine)

CO2 partial pressure (kPa)

0.498 0.524 0.547 0.567 0.599

5.5 11 25.8 52.7 106.5

0.499 0.521 0.548 0.565 0.595

5.1 11.1 26 52.5 101.3

Fig. 5. Comparison of CO2 absorption rate and CO2 capacity in 1.5 M aqueous amine solutions at 313 K and CO2 partial pressure at 15 kPa.

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Fig. 6.

13

C NMR spectrum of protonation in DEAB solutions.

Table 2 Solubility of CO2 in 1.5 M aqueous alkanolamine solution at 313 K.

MDEA A, B C, D

DEAB A, B C, D

IPAB A, B C, D

P (kPa)

CO2 , loading (mol CO2 /mol amine)

15.1 30 50.1 101.3 289.56 236.54

0.497 0.602 0.711 0.896 −325.5 −57.61

15.1 30 50.1 101.3 57,441 168,262

0.945 0.981 1.032 1.078 −170,123 −55,543

15.1 30 50.1 101.3 155,754 439,173

0.945 0.976 1.006 1.036 −452,792 −142,092

The polynomial equation: ln(p) = A × ˛3 + B × ˛2 + c × ˛ + D; A, B, C, D are fitting parameters of the polynomial equations.

parameters are listed in Table 2. With this established model, it is easily used to predict the partial pressure or CO2 loading. On the other hand, it can be seen from Fig. 4 that the absorption rate of CO2 in 1.5 M aqueous IPAB solutions at 313 K following performed highest than that of DEAB and MDEA following order rate is: IPAB > DEAB > MDEA. 3.2. Calibration equation establishment To reproduce the method proposed by Shi et al. (2012b), 10 samples of DEAB with a concentration of 1.5 M were titrated by different amounts of HCl (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0) and analyzed on a Varian 400 MHz NMR instrument at 293 K. About 10% deuterium oxide was used as signal lock and drops of 1,4-dioxane was used as an internal standard. The 13 C NMR spectrum of samples with various protonated DEAB solutions at 1.5 M and 293 K is shown in Fig. 6, and the chemical shift values are given in Table 3, and C1 , C3 , C6 were selected for the establishment of calibration equations of DEABH+ /DEAB at 293 K, as suggested by Shi et al. (2012b), as shown in Fig. 7. The same work was repeated in aqueous IPAB solutions for obtaining the calibration equations at desired temperature. 5 samples of IPAB with a concentration of 1.5 M were titrated by different amounts of HCl (0, 0.2, 0.4, 0.6, 0.8, and 1.0 M) and analyzed on NMR instrument at 293 K. The 13 C NMR spectrum of samples with

Fig. 7. Calibration curves and equations of DEABH+ /DEAB.

various protonated IPAB solutions at 1.5 M and 293 K is shown in Fig. 8 and the chemical shift values are given in Table 4. The IPAB molecular structure contains seven carbons, which is a different chemical structure compared to that of DEAB found in Fig. 1. Diethyl directly connects to nitrogen atom ((CH3 CH2 )N-); however, isopropyl((CH3 )2 CHN-) connect to nitrogen atom in IPAB in which the steric hindrance effects exist. Peaks representing ion pairs of IPABH+ /IPAB marked cC1 to cC6 and dC1 to dC6 (Fig. 3) according to chemical shifts from the upfield to downfield on the NMR spectra cannot be separated due to very fast proton exchange between IPABH+ and IPAB, as shown in Fig. 8. There is one peak exhibiting almost double intensity (18–22 ppm) than others, which can be due to the symmetric methyl existing in IPAB molecular structure (cC1 to dC1 and cC3 to dC3 ). By comparison of the chemical shifts of these carbon signals, it was observed that the chemical shifts of cC1 , dC1 and cC3 , dC3 (Figs. 3 and 8) clearly decreased 3.355, 3.571 ppm, respectively, and 0.856 ppm decreased by cC6 , dC6 a lower sensitive shifts compared with that of DEAB which is mainly due to the increasing amounts of IPABH+ and the increased electronic density of these three carbons nuclear by formed IPABH+ . On the other hand, the chemical shifts of cC2 , dC2 , cC4 , dC4 rarely changed, 0.143, 0.771 ppm, which may be explained by the weakening proton transfer effect that hardly affected the chemical surrounds of these carbons. The peak signal (cC5 , dC5 ) also moved to downfield with changed chemical shits at −2.649 ppm, the same as that of DEAB. Though the chemical shifts of C4 increased to 2.649 ppm, it moved to downfield region, which is a converse process compared to that of moving to upfield. In this work, to reduce the systematic error, C1 , C3 , C6 were selected for establishment of the calibration curves, as shown in Fig. 9.

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195

Table 3 Chemical shifts of carbon signals of various protonation DEAB. Titration ratio of DEAB (%)

0 10 20 30 40 50 60 70 80 90 100 Changes

Chemical shifts of carbon peaks (ppm) ıC1

ıC2

ıC3

ıC4

ıC5

ıC6

10.417 10.222 10.014 9.778 9.597 9.403 9.196 9.064 8.864 8.682 8.484 1.933

22.583 22.54 22.498 22.453 22.448 22.431 22.417 22.413 22.416 22.417 22.407 0.176

34.034 33.807 33.564 33.307 33.109 32.902 32.68 32.536 32.319 32.122 31.908 2.126

46.122 46.256 46.392 46.529 46.684 46.836 46.994 47.101 47.254 47.392 47.549 −1.427

48.662 48.7 48.676 48.682 48.732 48.784 48.846 48.891 48.961 49.025 49.094 −0.432

67.041 66.941 66.824 66.66 66.532 66.392 66.232 66.132 65.965 65.811 65.656 1.385

Fig. 8.

13

C NMR spectrum of protonation in IPAB solutions; [IPABH+ ]: [IPAB] = 0–1.

Table 4 Chemical shifts of carbon signals of protonation IPAB. Titration ratio of IPAB (%)

0 20 40 60 80 100 Changes

3.3.

13 C

Chemical shifts of carbon peaks (ppm) ıC1

ıC2

ıC3

ıC4

ıC5

ıC6

21.494 20.748 19.947 19.131 18.549 18.139 3.355

22.454 22.402 22.365 22.328 22.322 22.311 0.143

37.897 37.047 36.138 35.146 34.46 34.326 3.571

43.066 42.832 42.626 42.422 42.297 42.295 0.771

48.194 48.78 49.444 50.183 50.733 50.843 −2.649

66.548 66.371 66.156 65.899 65.721 65.692 0.856

NMR analysis

With these calibration equations, the main components at various CO2 loadings (0–0.94 mol of CO2 /mol of amine) in aqueous IPAB solutions (IPAB, IPABH+ , CO3 2− , and HCO3 − ) at 293 K can be determined by 13 C NMR technology. Several 13 C NMR spectra of IPAB-CO2 -H2 O system are summarized in Fig. 10 and Table 5. It can be observed from Fig. 10 that there are only six peaks that represent IPABH+ /IPAB in the range of 10–70 ppm which can be due to the very fast proton exchange of these two ions and cannot be separated on the spectra. There is only one peak in the

range of 160–170 ppm, which represents the pair of HCO3 − and CO3 2− . This is because the proton exchange between HCO3 − and CO3 2− is too fast to be separated (Jakobsen et al., 2005). At the beginning of the absorption experiment, there are no HCO3 − /CO3 2− peaks detected (˛CO2 ,loading ≤ 0.15), which is mainly because the amounts of these ion were too small and cannot be detected by NMR instrument. The concentration of liquid phase ions is plotted in Fig. 11 and shown in Table 6. It was found that the amounts of free amine decreased as the CO2 loading increased. This can be due to the chemical reaction between CO2 and free amine, as well as the amine

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B. Liu et al. / International Journal of Greenhouse Gas Control 50 (2016) 190–197

Table 5 The chemical shifts of carbon signals in IPAB-CO2 -H2 O system with various CO2 loadings (0–0.94) at 293 K. Carbon (ppm)

ıC1 ıC2 ıC3 ıC4 ıC5 ıC6

CO2 loading (mol CO2 /mol amine) 0

0.06

0.12

0.15

0.18

0.36

0.55

0.72

0.94

21.472 22.453 37.873 43.062 48.208 66.54

21.475 22.452 37.879 43.064 48.206 66.543

21.358 22.439 37.741 43.015 48.289 66.517

21.141 22.442 37.483 42.945 48.459 66.44

20.876 22.434 37.171 42.852 48.661 66.359

19.771 22.398 35.869 42.448 49.473 65.999

18.964 22.375 34.933 42.189 50.1 65.748

18.619 22.363 34.546 42.136 50.424 65.659

18.417 22.353 34.336 42.19 50.695 65.64

Fig. 9. Calibration curves and equations of IPABH+ /IPAB.

protonation as shown in Eqs. (1), (2) and (6), respectively. Then it led to an increasing amount of protonated amine (IPABH+ and DEABH+ ) as the CO2 loading increased. No carbamates were detected in both DEAB-CO2 -H2 O and IPAB-CO2 -H2 O system in the whole absorption process, which can be explained by the catalytic hydration mechanism in the former system, while in the IPAB-CO2 -H2 O system, it may form the unstable carbamates and quickly decomposed because of the steric hindrance effect of chemical structure by two symmetrical methyl next to the nitrogen atom. It can be seen from

Fig. 10.

13

Fig. 11. Ion speciation plot of 1.5 M IPAB aqueous solutions at various CO2 loadings and 293 K.

Figs. 10 and 11 that as the CO2 loading increased, CO3 2− was found to increase to a maximum, and then it decreased as the CO2 loading increased further and the peak shifts of this pairs moved to upfield (decreased chemical shifts) with the increasing amounts of bicarbonate. This is because the aqueous amine solutions were strongly basic at initial time, and CO3 2− was observed to be a major component rather than HCO3 . As injection of more CO2 , the solution became weakly basic. Thus, CO3 2− was converted to HCO3 through

C NMR spectrum of IPAB-CO2 -H2 O system with various CO2 loadings at 293 K.

B. Liu et al. / International Journal of Greenhouse Gas Control 50 (2016) 190–197 Table 6 The ion speciation concentration in the IPAB-CO2 -H2 O system determined by from 0 to 0.94 at 293.15 K. CO2 loading (mol CO2 /mol amine)

[IPAB] (mol/L)

0 0.15 0.18 0.36 0.55 0.72 0.94

1.5 1.389 1.275 0.796 0.446 0.296 0.209

13

197

C NMR, initial concentration of aqueous IPAB solutions was 1.5 M and CO2 loading ranges

[IPABH+ ] (mol/L)

[CO3 2− ] (mol/L)

[HCO3 − ] (mol/L)

ıHCO

3

− /CO 2− 3

(ppm)

– 0.111 0.225 0.704 1.054 1.204 1.291

the reverse reaction of CO2 reacting with amine and CO2 reacting with water, as shown in Eqs. (1) and (3), respectively.

– 0.232 0.370 0.351 0.208 0.062

– 0.038 0.170 0.474 0.872 1.348

– 167.118 165.835 163.922 162.209 160.469

Education of China (No. IRT1238), and China State Project 985 in Hunan University Novel Technology Research & Development for CO2 Capture.

4. Conclusions References In this work, the CO2 solubility and absorption rate in novel aqueous amine (IPAB, DEAB) solutions and conventional MDEA solvents at 313 K and low CO2 partial pressure (15-100 kPa) were investigated. The new solvent (IPAB) performed better CO2 absorption properties than that of DEAB and MDEA. The validation test of NMR calibration test was performed based on 1.5 M aqueous DEAB solvents at 293 K. The results showed that the NMR calibration test showed a high accuracy for determining the exact amount of protonated amine and free amine in amine-CO2 -H2 O system (99.7% for DEAB and around 97% for IPAB). Compared with the titration ratio as a reference standard, the quantitative results of free amine and protonated amine exhibited a deviation of about 3% in protonated DEAB solution and about 10% in protonated IPAB solution. Then the NMR calibration method was applied into the 1.5 M aqueous IPAB solutions for analysis of components in the liquid phase at 293 K to generate a useful database. For NMR calibration, it is very important to perform NMR peaks calibration first, and then perform peak assignment, peak area integration, zero-line correction onto spectra interpretation, and data calculation to generate good ion speciation data. The comparison between DEAB-CO2 -H2 O system and IPAB-CO2 -H2 O system thus helps us to better understand the reaction mechanisms which will help to appropriately select a solvent that can improve the CO2 absorption rate and reducing energy consumption. In this work, the calibration equations of IPABH+ /IPAB were firstly built at 293 K with initial concentration of aqueous IPAB solutions at 1.5 M by titration for preparing different ratios of IPABH+ /IPAB (0, 0.2, 0.6, 0.8 and 1.0), which was used to investigate these two ions exact amounts in the IPAB-CO2 -H2 O system. Acknowledgements The authors thank the financial supports from the National Natural Science Foundation of China (21476064) and 21406057 Innovative Research Team Development Plan-Ministry of

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