Journal Information
Vol. 8. Num. 1.
Pages 1-1592 (January - March 2019)
Share
Share
Download PDF
More article options
Visits
938
Vol. 8. Num. 1.
Pages 1-1592 (January - March 2019)
Original Article
DOI: 10.1016/j.jmrt.2017.08.014
Open Access
Effects of layered double hydroxides incorporation on carbonation resistance of cementitious materials
Visits
938
Juntao Maa,d, Ping Duanb,c,d,
Corresponding author
, Daming Renb,c, Wei Zhoub,c
a School of Civil Engineering and Communication, North China University of Water Resources and Electric Power, Zhengzhou 450045, P.R. China
b Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
c Engineering Research Center of Nano-Geomaterials of Ministry of Education, China University of Geosciences, Wuhan 430074, China
d State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
This item has received
938
Visits

Under a Creative Commons license
Article information
Abstract
Full Text
Bibliography
Download PDF
Statistics
Figures (7)
Show moreShow less
Tables (3)
Table 1. Chemical composition of Portland cement and fly ash (wt%).
Table 2. Chemical composition of LDHs (mass%).
Table 3. Wave numbers correspond to infrared absorption band of LDHs (cm−1).
Show moreShow less
Abstract

The development of new or modified cementitious materials is an important part of existing strategies to improve performance and minimize life-cycle costs and to eliminate the CO2's impact on durability. The high anion exchange capacity of layered double hydroxides (LDHs) materials makes their interlayer ion exchange by organic and inorganic anions versatile and easily achieved. LDH-like materials could be used in cementitious materials for their CO32− capturing capacity and to enhance carbonation resistance of cementitious materials.

In this work, original LDHs were synthesized, LDHs calcined at 500, 550 and 600°C, respectively, were prepared. Power X-ray diffraction (XRD), IR-spectroscopy and thermal analysis (TG–DSC) were employed to characterize the component and structural changes of these types of LDHs before and after CO2 capture. Carbonation resistance of cement paste incorporating LDHs was experimentally evaluated for assessment of CO2 capture capacity of LDHs. Ion exchange mechanism of LDHs was also analyzed from adsorption experiments.

The results show that LDH-like materials could be used for their CO32− capturing capacity to enhance carbonation resistance of concrete as well as to eliminate CO2's impact on durability aspect especially the LDHs calcined at 600°C. Calcined LDHs fulfill the structure regeneration after CO2 capture. LDHs have positive effect on improvement of carbonation resistance of cement paste especially at later curing stages.

Keywords:
Layered double hydroxides (LDHs)
Carbonation
Anion exchange
Adsorption
Cementitious materials
Full Text
1Introduction

In urban and industrial areas, where environmental pollution results in a significant concentration of CO2, carbonation-initiated reinforcement corrosion prevails. Recognition of the role of anthropogenic carbon dioxide's impact on climate change in recent years has led to the need for worldwide commitments in reducing carbon dioxide (CO2) and other greenhouse gases.

Therefore, research is currently conducted at various institutions to develop new and improved construction materials, rehabilitation and repair technologies, and a better understanding of the physical and chemical mechanisms that lead to deterioration. The improved knowledge will enable designers not only to properly rehabilitate and maintain the current stock of concrete structures, but also to improve the durability of future structures by giving, in the design stage, proper consideration to the environment and conditions. And the most important strategy is how to control the carbonation process, therefore, establishing and developing new technology for inhibiting carbonization reaction of concrete materials is the guarantee of good durability of modern concrete contains large amounts of mineral admixtures.

Hydrotalcite-like compounds (HTLCs) are a class of layered compounds that are receiving attention both as technical materials and as geologically significant phases that influence the cycling of aqueous species in the environment.

Among the group of minerals referred to as hydrotalcite-like compounds [1], the ‘layered double hydroxides’ (LDHs) have many physical and chemical properties that are surprisingly similar to those of clay minerals. Their layered structure, wide chemical compositions (due to variable isomorphous substitution of metallic cations), variable layer charge density, ion-exchange properties, reactive interlayer space, swelling in water, and rheological and colloidal properties make LDHs clay-like. But because of their anion-exchange properties, LDHs were referred to as ‘anionic clays’. Naturally occurring hydrotalcite, Mg6Al2(OH)16CO3·4H2O, and synthetic hydrotalcite-like compounds, also called layered double hydroxides (LDHs), have been investigated for many years [2,3]. Taylor [4] described these phases as being structurally related to brucite the same way the AFm phases are to Portlandite. The formula of the LDHs can be generalized to [M2+1−xM3+x(OH)2]x+[Anx/n·mH2O]x, where “x” represents the mole fraction (based on 1mol of cations) in the brucite layer, M2+can be Mg2+, Zn2+, Mn2+, Ca2+, etc.; M3+: Al3+,Ga3+, Fe3+, Cr3+, etc.; and An−: NO3, Cl, CO32−,SO42−, etc. [5].

The structure of an LDH is basically built up from the parent structure brucite Mg(OH)2 by isomorphous substitution of divalent cations (shown in Fig. 1). The replacement of Mg2+ by M3+ ions generates an excess of positive charge within the inorganic layers, which has to be balanced by incorporation in the interlayer space of anions, such as NO3, Cl, CO32−, SO42−, etc. In addition to anions, the interlayer space region can also contain water molecules connected to the inorganic layers via hydrogen bonding.

Fig. 1.

Schematic diagram of LDHs structure.

(0.16MB).

The high anion exchange capacity of LDH-like materials makes their interlayer ion exchange by organic and inorganic anions versatile and easily achieved [6–8]. LDHs have been studied extensively for a wide range of applications utilizing catalysts [9,10], ceramic precursors [11] adsorbents [12], and bio-organic nanohybrids [13,14]. Recent research has shown great flexibility of the LDH-like materials in tailoring the chemical and physical properties of materials to be used for specific applications, e.g., molecular recognition, optical storage, batteries, etc. [15,16].

LDH solid solutions are common secondary phases in the contact zone between clays and cementitious materials. In addition to the direct synthesis by coprecipitation from salt precursors, LDHs have been subject of many post-synthesis transformations involving their well-known memory effect property and ion-exchange capacity.

These hydroxides exhibit a selectivity for the anions in the sequence CO32−>SO42−>HPO42−>F>Cl>B(OH)4−>NO3, therefore, LDH-like compounds can be used as host materials for a variety of anions of interest to cement scientists. LDH-like materials could be used in cement and concrete for their CO32− capturing capacity and to enhance carbonation resistance of concrete.

In this study, we examined the effects of LDHs containing Mg and Al on carbonation resistance of cementitious materials. Power X-ray diffraction (XRD), IR-spectroscopy and thermal analysis (TG–DSC) were employed to characterize the component and structural changes of these types of LDHs before and after CO2 capture. Carbonation resistance of cement paste incorporating LDHs was experimental evaluated for assessment of CO2 capture capacity of LDHs. Ion exchange mechanism of LDHs was also analyzed from adsorption experiments and structure evolution.

2Experimental2.1Materials

Portland cement (CEM I 42.5) (relative density 3100kg/m3, specific surface area 369.6m2/kg) was used as binder in the study. Fly ash was used as mineral admixture. Their chemical compositions are shown in Table 1. Cement paste samples were prepared for carbonation test and micro-analysis. The replace level of cement by fly ash was 30% at a constant water/binder (w/b) ratio of 0.4.

Table 1.

Chemical composition of Portland cement and fly ash (wt%).

  SiO2  Fe2O3  Al2O3  CaO  MgO  SO3  LOI  Sum 
Cement  21.35  3.31  4.67  62.60  3.08  2.25  0.95  98.21 
Fly ash  49.67  4.20  35.13  3.09  0.82  0.57  1.97  95.45 

Samples prepared for this study were synthesized using a “memory-effect”-based synthesis route. That is, by recovering of the layered structure through calcination of the starting hydrotalcite and subsequent contact of the derived mixed oxide with solutions containing many different anions, or by direct exchange of the anions located in the interlayer space by others, an impressive variety of hydrotalcite-derived compounds have been synthesized.

Mg–Al–CO3 hydrotalcites was synthesized using a conventional coprecipitation method. A salt solution (200mL) containing appropriate ratios of MgCl2·6H2O (1.2mol/L) and AlCl3·6H2O (0.4mol/L) was created. Solution (200mL) containing NaOH and Na2CO3, at sufficient concentrations were also created to precipitate the salt in the first solution. The two solutions were simultaneously added drop by drop into a 200mL sample of deionized water, which were vigorously stirred. The temperature was fixed at 313K, and the pH was maintained at 10–11. The resulting slurry was allowed to rest at 338K for 12h. The final precipitate was centrifuged several times with deionized water, until the superstratum water was free of Cl. The precipitate was then dried at 378K for 8h to obtain the Mg–Al–CO3 type hydrotalcite powder.

Hydrotalcite-like compounds Mg–Al–CO3 type hydrotalcite were first synthesized experimentally and then calcined at 500, 550 and 600°C, respectively, for 4h with a heating rate of 3°C/min from ambient temperature, and cooled naturally to ambient temperature. Chemical composition of LDHs is measured and listed in Table 2.

Table 2.

Chemical composition of LDHs (mass%).

  SiO2  Al2O3  Fe2O3  CaO  MgO  Na2SO3  K2LOI 
Original LDHs  0.02  20.75  –  0.06  34.27  1.8  1.77  –  41.02 
Calcinated LDHs  0.09  34.72  –  0.12  55.07  2.64  3.02  –  4.17 

Calcinations of original LDHs lead to dehydration and decarbonization, hence there exist chemical composition differences between original LDHs and calcined LDHs, especially the high content of Al2O3 and MgO in calcined LDHs.

2.2Casting and curing

Content of LDHs was kept at constant 2% by weight of binder including cement and fly ash. The mixing sequence employed consists of dry mixing of binders including cement, fly ash and LDHs for 30s. After ensuring proper mixing of all the solid components, polycarboxylates superplasticizer was added into water and the addition of liquids including water and superplasticizer into the dry solids was completed during 30s. Finally, the mixing between the liquids and solids was continued for further 3min.

Specimens with the dimensions of 40mm×40mm×40mm were mixed and then cast in molds for various tests. The specimen surfaces were covered with polyethylene sheets to prevent loss of moisture. After 24h, all specimens were demolded and cured at the temperature of 20±2°C and the relative humidity of 95% until the testing days.

2.3Characterization

The powder X-ray diffraction (XRD) was performed on a D8 Advance X-Ray diffractometer at 45kV and 35mA with a graphite secondary monochromator to characterize the precipitated solids. The diagrams were recorded with Cu Kα radiation at ambient temperature within a 2θ-range from 5° to 75°, using a step size of 0.02°/s.

The compositions of the hydrotalcites bearing anions samples were analyzed using an inductively coupled plasma-mass spectrometer (ICP/MS) for the Mg and Al content, and the anion content was determined using a ion chromatograph. The content of interlayer water in these solid samples was determined by a Seiko simultaneous thermal analyzer (STA) TG/DSC in flowing Ultra zero air (150mL/min) from room temperature to 1000°C with a heating rate of 20°C/min.

3Results and discussion3.1XRD patterns analyses of hydrotalcite-like compounds

As shown in Fig. 2, the transformation of the crystalline LDH phase (O-LDHs) to nearly amorphous mixed oxide (C-LDHs) was characterized by XRD. In the XRD patterns of LDHs (shown in Fig. 2), the basal reflections from (003), (006), etc., planes and the reflection from the (110) plane are indicative of the formation of a Mg–Al–CO3 LDH material [2]. All the solids including original LDHs, and LDHs calcined at 500, 550 and 600°C, respectively, after CO2 capture (hereafter were referred to as C-O-LDHs, C-500C-LDOs, C-550C-LDOs and C-600C-LDOs, respectively) display powder X-ray diffraction spectra typical of LDH materials (shown in Fig. 2). However, the broad peaks are presumably due to the simultaneous effects of small coherent domain size and structural disorder after calcinations at different temperature. The XRD patterns of LDHs indicate that the layer structure does not collapse with the loss of interlayer water.

Fig. 2.

XRD patterns analyses of different types of LDHs.

(0.12MB).
3.2Thermal decomposition of hydrotalcite-like compounds

According to the literature [17–19] the thermal decomposition of LDHs includes three main stages, i.e., the removal of interlayer water, the decomposition of structural hydroxyl groups and finally the decomposition of interlayer carbonate anions as shown in Figs. 3 and 4.

Fig. 3.

TG/DSC of Mg–Al–CO3 type hydrotalcite.

(0.1MB).
Fig. 4.

Mass spectrometry of Mg–Al–CO3 type hydrotalcite.

(0.1MB).

The results show an initial reduction in weight between RT and 200°C arising from physical absorbed and interlayer water (see the first peak of H2O in Fig. 4). A second weight loss between 200 and 400°C results from a concomitant dehydroxylation of the layers and a reduction of CO32− to CO2 (see the second peak of H2O and peaks of CO2 in Fig. 4). A temperature treatment beyond 500°C caused a collapse of the layered structure for all compounds and gave rise to new crystalline phases due to the decomposition of interlayer carbonate anions (see the last peak of CO2 in Fig. 4) (mixed oxides, e.g., spinel forms).

3.3Infrared analysis of LDHs before and after carbonation test

The carbonation test was done inside a chamber with a CO2 concentration ≈20%±3%, RH70%±5%, and T20°C±3°C. Different series of LDHs was mixed with water with constant ratio of 1:10, which were vigorously stirred. After that, the solutions were moved into the carbonation chamber for 24h.

FTIR spectroscopy showed characteristics frequencies associated with the types of LDHs. Fig. 5 shows the FT-IR spectra of LDHs calcined at different temperature before and after CO2 capture. Original LDHs before and after CO2 capture hereafter were referred to as O-LDH and CO-LDH, respectively. LDHs calcined at 600°C before and after CO2 capture hereafter were referred to as C-LDH and CC-LDH, respectively. Calcinated LDHs mixing with water for structure regeneration before and after CO2 capture hereafter were referred to as R-LDH and CR-LDH, respectively.

Fig. 5.

Infrared analysis of LDHs before and after CO2 capture.

(0.12MB).

Table 3 summaries the wave numbers correspond to infrared absorption band of LDHs before and after CO2 capture.

Table 3.

Wave numbers correspond to infrared absorption band of LDHs (cm−1).

  O-LDH  C-LDH  R-LDH 
Bending vibration of –OH  1637  1636  1637 
Stretching vibration of –OH  3442  3454  3461 
Stretching vibration of C–O  1360  1409  1364 
Bending vibration of CO32−  789–673  813  782–671 

In Fig. 5 and Table 3, absorption band of stretching vibration of C–O, shift to higher wave number (from 1360 to 1409) in the process of O-LDH changes to C-LDH after calcination, and absorption band of stretching vibration of C–O, shift to lower wave number (from 1409 to 1364) in the construction regeneration process of C-LDH changes to R-LDH after mix with water. Similar wave number corresponding to C–O, CO32− of O-LDH and R-LDH indicates reconstruction of layered structure of LDHs.

In all the curves, the absorption band of the three types of LDHs before and after carbonation are similar, the intensity of absorption band of stretching vibration of C–O increases after carbonation, it shows the content of CO32− in layered structure of LDHs increases after carbonation, especially for the C-LDH. The absorption band of O-LDH, CO-LDH, C-LDH, CC-LDH indicates that the intensity of bending vibration of –OH decreases after carbonation, some factors leading to this phenomenon can be summarized as following: (1) CO2 changes to CO32− when mixing with water molecular, and ion exchange occurs between CO32− and OH, therefore, OH was substituted by CO32−; (2) samples are mix with water before carbonation, water molecular enters into the layered structure and the increasing interlayer spacing is beneficial for intercalation and exchange of CO32−; (3) acid gas CO2 will lower the pH of cement paste.

3.4Impact of structure evolution on CO2 sorption

Evolution of the structure taking place during and after the thermal decomposition of the Mg–Al–CO3 LDHs is very important for understanding its CO2 sorption properties. In the crystalline phase, LDHs consists of positively charged Mg–Al–OH brucite type layers in an octahedral network. The surface and structural properties of LDHs in this phase are not suitable for reversible CO2 sorption, as the Mg–OH-rich network in the crystalline LDHs has been found to favor base-catalyzed reactions. Hence, the sorption in this phase is mostly attributed to the acid–base reaction of Mg–OH and CO2 forming Mg(HCO3)2, which is considered to be irreversible sorption.

On the other hand, LDHs completely loses interlayer water and dehydroxylates to a large extent upon heating to 600°C, leading to the formation of a mixed oxide with a three dimensional network. Although a fair amount of carbonate still remains in the structure, this gives a relatively high surface area and exposes sufficient basic sites on the surface. These basic sites favor reversible CO2 sorption in a form as follows

Mg–O+CO2=Mg–O⋯CO2 (ad)

The interaction between the adsorbed CO2 and the basic sites seems to be mainly responsible for CO2 sorption at 600°C. The experimental results obtained in our studies suggest that this interaction is not as weak as in the case of zeolite but not as strong as in the case of alkali metal oxide. These results strongly suggest the potential of LDOs use as a CO2 sorbent in flue gas systems at temperatures around 600°C and above.

However, the R-LDH accumulates significant mass during its aging period because of interactions with atmospheric water and CO2. This led to the hydroxylation of metal oxides, particularly on the surface, with a partial revival of the crystalline LDHs structure in addition to the physical bonding of water. The same diffraction peaks of O-LDHs and R-LDHs by XRD analysis indicate reconstruction of C-LDHs after reaction with water. The XRD patterns of LDHs before and after calcinations indicate that the regeneration of layer structure of calcined LDHs, which leads to hydroxylation of mental oxides. The results of FTIR of LDHs and concrete before and after carbonation also confirm a successful intercalation of CO32− in DLHs, which fulfills the structure regeneration, i.e., the revival of the crystalline LDHs structure [20].

The partial reconstruction of the mixed oxide to the LDHs phase on the surface of the R-LDH sample thus decreases the CO2 sorption capacity. As a consequence, recalcination of the R-LDH restores both the amorphous mixed oxide and CO2 sorption capacity [20]. On account of these observations, either vacuum storage of the LDOs or in situ calcination methods were used for all further CO2 sorption measurements. In the in situ calcination method, LDHs was calcined in conjunction with CO2 sorption measurements. These methods produced highly consistent sorption values.

3.5Adsorption experiments

Adsorption equilibrium for CO32− by LDHs was achieved within 100h, whereas more than 700h were needed for calcined LDHs (LDOs) (Fig. 6). This indicates that the adsorption mechanism of CO32− to LDH is different from that of LDO. Layered double hydroxide exhibits selectivity for the anions in the sequence CO32−>SO42−>Cl, therefore, ion exchange will not occur between CO32− and untreated Mg–Al–CO3 type LDHs, CO32− was adsorbed on external surface of LDH. However, LDH calcined at 600°C, namely, LDOs, provides large amounts of basic sites for CO32− to occupy in the interlayers, therefore, adsorption mechanism of CO32− to LDOs are structure regeneration through memory effect.

Fig. 6.

Time dependence of adsorption of CO32− by LDHs and LDOs.

(0.08MB).

Additionally, larger sulfate anions with higher electric charge can intercalate easily between the layers to maintain electroneutrality or exchange other anions. Planar structure of CO32− leads to the most stable structure forms only when it intercalates parallelly with the layer structure. Therefore, interlayer spacing decreases when CO32− intercalates between the layers, basic sites for CO32− are less and adsorption equilibrium for CO32− in LDHs achieves within shorter time compared to LDOs.

3.6Carbonation depth of cement paste

The carbonation depth of cement paste mixtures containing LDHs is plotted as a function of carbonation ages in Fig. 7.

Fig. 7.

Carbonation depth of cement paste mixtures containing LDHs at different ages.

(0.08MB).

In Fig. 7, carbonation depth of all samples decreases with addition of calcined LDHs regardless of curing ages, however, the reduction at early ages (14 days) is negligible, carbonation depth results indicate that LDHs have positive effect on improvement of carbonation resistance of cement paste especially for sample at 42 days with the most dramatic reduction of carbonation depth, i.e., 30.8%. At 14 days, the effect of LDHs on the improvement of carbonation depth is not significant as later curing stages. However, after 28 days, carbonation depth of all samples decreases significantly when incorporating LDHs.

The results shown in Fig. 7 indicate that LDHs have positive effect on improvement of carbonation resistance of cement paste especially at later curing stages. Calcined LDHs will adsorb large amounts of CO32− anions in layer with the change of CO32− to CO2 after calcinations, and the reconstruction after reaction with H2O and CO2 leads to consumption of large amounts of CO2 in cement paste.

4Conclusions

The component and structural changes of original LDHs, LDHs calcined at 500, 550 and 600°C, respectively, before and after CO2 capture, carbonation resistance of cement paste incorporating LDHs and ion exchange mechanism of LDHs from thermodynamic calculation were presented in this paper. From the results obtained in this study, the following conclusions can be drawn:

  • (1)

    LDH-like materials could be used in cement and concrete for their CO32− capturing capacity and to enhance carbonation resistance of concrete as well as eliminate carbon dioxide's impact on climate change especially the LDHs calcined at 600°C.

  • (2)

    All the solids including original LDHs, and LDHs calcined at 500, 550 and 600°C, respectively, after CO2 capture display powder X-ray diffraction spectra typical of LDHs materials. Broad peaks are presumably due to the simultaneous effects of small coherent domain size and structural disorder after calcinations at different temperature.

  • (3)

    Thermal decomposition of LDHs includes three main stages, i.e., the removal of interlayer water, the decomposition of structural hydroxyl groups and finally the decomposition of interlayer anions.

  • (4)

    The content of CO32− in layered structure of LDHs increases after CO2 capture. LDHs have positive effect on improvement of carbonation resistance of cement paste especially at later curing stages.

Conflicts of interest

The authors declare no conflicts of interest.

Acknowledgements

This work was financially supported by National Natural Science Foundation of China (No. 51508191 and No. 51502272), the Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan) (No. G1323511668), the Foundation from State Key Laboratory of Silicates Materials for Architectures of Wuhan University of Technology (SYSJJ2014-3, SYSJJ2018-15), and the Opening Project of Engineering Research Center of Nano-Geo Materials of Ministry of Education, China University of Geosciences (NGM2018KF011).

References
[1]
A.C.D. Newman.
Chemistry of clays and clay minerals.
Wiley-Interscience, (1987),
[2]
C. Cavani, E. Trfiro, A. Vaccari.
Hydrotalcite-type anionic clays: preparation, properties and applications.
Catal Today, 11 (1991), pp. 173-201
[3]
I.A. Khan, D. Ohare.
Intercalation chemistry of layered double hydroxides: recent developments and applications.
J Mater Chem, 12 (2002), pp. 3191-3198
[4]
H.F.W. Taylor.
Cement chemistry.
2nd ed., Thomas Telford Publishing, (1997),
[5]
V.R.L. Constantino, T.J. Pinnavaia.
Basic properties of Mg2+1−x Al3+x layered double hydroxides intercalated by carbonates, hydroxide, chloride, and sulfate anions.
Inorg Chem, 34 (1995), pp. 883-892
[6]
S. Carlino.
The intercalation of carboxylic acids into layered double hydroxides: a critical evaluation and review of the different methods.
Solid State Ionics, 98 (1997), pp. 73-84
[7]
E.A. Gardner, K.Y. Sang, T. Kwon, T.J. Pinnavaia.
Layered double hydroxides pillared by macropolyoxometalates.
Appl Clay Sci, 13 (1998), pp. 479-494
[8]
L. Raki, D.G. Rancourt, C. Detellier.
Preparation, characterization, and Mossbauer spectroscopy of organic anion intercalated pyroaurite-like layered double hydroxides.
Chem Mater, 7 (1995), pp. 221-224
[9]
A. Beres, I. Palinko, I. Kiricsi, J.B. Nagy, Y. Kiyozumi, F. Mizukami.
Layered double hydroxides and their pillared derivatives-materials for solid base catalysis: synthesis and characterization.
Appl Catal A: Gen, 182 (1999), pp. 237-247
[10]
V. Rives, M.A. Ulibarri.
Layered double hydroxides (LDH) intercalated with metal coordination compounds and oxometalates.
Coord Chem Rev, 181 (1999), pp. 61-120
[11]
A. Alejandre, F. Medina, P. Slargre, X. Correig, J.E. Sueiras.
Preparation and study of Cu–Al mixed oxides via hydrotalcite-like precursors.
Chem Mater, 11 (1999), pp. 939-948
[12]
P.C. Pavan, G. Gomes, J.B. Valim.
Adsorption of sodium dodecyl sulfate on layered double hydroxides.
Microporous Mesoporous Mater, 21 (1998), pp. 659-665
[13]
J.H. Choy, S.Y. Kwak, J.S. Park, Y.J. Jeong, J. Portier.
Intercalative nanohybrids of nucleoside monophosphates and DNA in layered metal hydroxide.
J Am Chem Soc, 121 (1999), pp. 1399-1400
[14]
N.T. Whilton, P.J. Vickers, S.J. Mann.
Bioinorganic clays: synthesis and characterization of amino- and polyamino acid intercalated layered double hydroxides.
J Mater Chem, 7 (1997), pp. 1623-1629
[15]
G.A. Caravaggio, C. Detellier, Z. Wronski.
Synthesis, stability and electrochemical properties of NiAl and NiV layered double hydroxides.
J Mater Chem, 11 (2001), pp. 912-921
[16]
B. Lotsch, F. Millange, R.I. Walton, D. Ohare.
Separation of nucleoside monophosphates using preferential anion exchange intercalation in layered double hydroxides.
Solid State Sci, 3 (2001), pp. 883-886
[17]
S. Miyata.
Physicochemical properties of synthetic hydrotalcites in relation to composition.
Clays Clay Miner, 28 (1980), pp. 50-56
[18]
V. Rives.
Characterisation of layered double hydroxides and their decomposition products.
Mater Chem Phys, 75 (2002), pp. 19-25
[19]
V. Vagvolgyi, S.J. Palmer, J. Kristof, R.L. Frost, E. Horvath.
Mechanism for hydrotalcite decomposition: a controlled rate thermal analysis study.
J Colloid Interface Sci, 318 (2008), pp. 302-308
[20]
P. Duan, W. Chen, J.T. Ma, Z.H. Shui.
Influence of layered double hydroxides on microstructure and carbonation resistance of sulphoaluminate cement concrete.
Constr Build Mater, 48 (2013), pp. 601-609
Copyright © 2018. Brazilian Metallurgical, Materials and Mining Association
Journal of Materials Research and Technology

Subscribe to our newsletter

Article options
Tools
Cookies policy
To improve our services and products, we use cookies (own or third parties authorized) to show advertising related to client preferences through the analyses of navigation customer behavior. Continuing navigation will be considered as acceptance of this use. You can change the settings or obtain more information by clicking here.