Ca Al Layered Double Hydroxides Research Articles

Reactivity and Heavy Metal Removal Capacity of Calcium Alginate Beads Loaded with Ca–Al Layered Double Hydroxides

Layered double hydroxides (LDHs) present multiple applications due to their versatility and reactivity. Thus, Ca–Al LDHs with Friedel’s salt structure (HC) have been proposed as heavy metal scavengers due to their buffering capacity at basic pHs. Nevertheless, the control of the reactivity of LDHs such as HC is necessary to optimize their applications. Here, the reactivity of an HC prepared by a coprecipitation method was modified by its inclusion in calcium alginate (CaAlg) beads prepared by ionic gelation. The obtained beads (CaAlg/HC) showed good dispersion of the HC particles in the alginate matrix and were used to test the acid base reactivity and heavy metal uptake capacity compared with pure CaAlg beads and HC powder separately. The pH buffering capacity of CaAlg beads was enriched by the inclusion of HC that, in turn, was modulated in its reactivity. Thus, the HC dissolution times changed from mere seconds for the powder to tens of minutes when enclosed in the beads in a kinetic profile determined by the diffusive step. On the other hand, Cu2+ uptake capacity of CaAlg/HC beads combined the Cu(OH)2 precipitation capacity of HC with the complexation capacity of alginate, reaching good affinity and capacity for the obtained beads. Nevertheless, the precipitation of the hydroxide was produced outside the bead, which would induce the addition of an additional separation step to produce an acceptable Cu2+ elimination.

Novel route to synthesize CaAl- and MgAl-layered double hydroxides with highly regular morphology

A facile, sol–gel method was developed to obtain Al-containing layered double hydroxides (LDHs) with Ca or Mg divalent cations. Ca- and Al-alkoxide were added to aqueous NaNO3 solution, and, after rapid gelation, a solid product, phase-pure, highly crystalline CaAl–LDH was formed with exceptionally regular morphology without impurities for the first time with sol–gel method. The lack of salt in the solution used for the hydrolysis resulted in a non-desirable by-product (katoite). For the sol–gel synthesis of MgAl–LDH, it was found that its formation was less sensitive to the presence of nitrate ions, and pure water or aqueous NaOH worked equally well. The product was also a highly crystalline material with thin, plate-like morphology as revealed by X-ray diffractometry and scanning electron microscopy. IR measurements indicate the lack of organic substance in the interlamellar space for both materials.

Super adsorption capability of rhombic dodecahedral Ca-Al layered double oxides for Congo red removal

In this work, a novel rhombic dodecahedral structure of Ca-Al-layered double hydroxides (Ca-Al-LDHs) was synthesized by a two-phase solvothermal method. Subsequently, Ca-Al layered double oxides (Ca-Al-LDOs) were obtained by calcinating Ca-Al-LDHs at 600 °C which maintained the rhombic dodecahedral structures well. The morphologies of as-obtained samples were characterized by both transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The phase structure and elemental composition were analyzed by X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS), respectively. Fourier transformed infrared (FT-IR) spectra were performed to confirm the existence of LDH structures. The Ca-Al-LDOs exhibited high adsorption rates and superb adsorption capacities for removal of Congo red (CR) from aqueous solution. The maximum adsorption capacities of Ca-Al-LDOs towards CR reached to 1536.1 mg g−1, which is extremely higher than most of hydrotalcite-like materials. The adsorption process of Ca-Al-LDHs and Ca-Al-LDOs were described by the Langmuir isotherm model and pseudo-second-order model well. The adsorption mechanisms mainly dominated by electrostatic adsorption, ion exchange process, hydrogen bonding interactions and surface complexation. This general strategy afforded a wide possibility to prepare a novel and advanced LDOs adsorption material for water treatment.

Selenite Uptake by Ca–Al LDH: A Description of Intercalated Anion Coordination Geometries

Layered double hydroxides (LDHs) are anion exchangers with a strong potential to scavenge anionic contaminants in aquatic environments. Here, the uptake of selenite (SeO32-) by Ca-Al LDHs was investigated as a function of Se concentration. Thermodynamic modeling of batch sorption isotherms shows that the formation of SeO32--intercalated AFm (hydrated calcium aluminate monosubstituent) phase, AFm-SeO3, is the dominant mechanism controlling the retention of Se at medium loadings. AFm-Cl2 shows much stronger affinity and larger distribution ratio (Rd ∼ 17800 L kg-1) toward SeO32- than AFm-SO4 (Rd ∼ 705 L kg-1). At stoichiometric SeO32- loading for anion exchange, the newly formed AFm-SeO3 phase results in two basal spacing, i.e., 9.93 ± 0.06 Å and ∼11.03 ± 0.03 Å. Extended X-ray absorption fine structure (EXAFS) spectra indicate that the intercalated SeO32- forms inner-sphere complexes with the Ca-Al-O layers. In situ X-ray diffraction (XRD) shows that basal spacing of Ca-Al LDHs have a remarkable linear relationship with the size of hydrated intercalated anions (i.e., Cl-, SO42-, MoO42-, and SeO32-). Contrary to AFm-SeO3 with inner-sphere SeO32- complexes in the interlayer, the phase with hydrogen-bonded inner-sphere complexed SeO32- is kinetically favored but thermodynamically unstable. This work offers new insights about the determination of intercalated anion coordination geometries via XRD analyses.

Solid base catalysts derived from Ca-M-Al (M = Mg, La, Ce, Y) layered double hydroxides for dimethyl carbonate synthesis by transesterification of methanol with propylene carbonate

Composite solid base catalysts derived from Ca-M-Al (M = Mg, La, Ce, Y) layered double hydroxides (LDH) were synthesized, characterized and applied to the transesterification of methanol with propylene carbonate. X-ray diffraction analyses of the catalysts show that all of the catalysts were in the form of composite oxides. Compared with the Ca-Al LDH catalyst, the specific surface areas and pore volumes of the catalysts were increased with the introduction of Mg, La or Ce. The catalytic performance of these catalysts increases in the order of Ca-Y-Al < Ca-Al < Ca-Ce-Al < Ca-La-Al < Ca-Mg-Al, which is consistent with the total surface basic amounts of these materials and the formation of especially strong basic sites following modification with Mg and La. The Ca-Mg-Al catalyst shows the highest (Ca+Mg):Al atomic ratio, indicating that it likely contains more unsaturated O2– ions, providing it with the highest concentration of very strong basic sites. The recyclability of these catalysts is improved following the addition of Mg, La, Ce or Y, with the Ca-Mg-Al maintaining a high level of activity after ten recycling trials. X-ray diffraction analyses of fresh and used Ca-Mg-Al demonstrate that this catalyst is exceptionally stable, which could be of value in practical applications related to heterogeneous catalysis.

Synergistic coagulation of GO and secondary adsorption of heavy metal ions on Ca/Al layered double hydroxides

With the extensive application of graphene oxide (GO), it is noticeable that part of GO is directly/indirectly released into the environment and widespread research indicated that it had adverse influences on human health and ecological balance. In this work, a novel nanobelt-like Ca/Al layered double hydroxides (CA-LDH) was synthesized and applied as efficient coagulant for the removal of GO from aqueous solutions. The results indicated that neutral pH, co-existing cations and higher temperature were beneficial to the coagulation of GO. The sequence of cation effect for promoting of GO coagulation was Ca2+ > Mg2+ > K+ > Na+, whereas the effect of anions on GO coagulation was PO43− > CO32− > SO42− > Cl−. Comparing with anions, the cations showed more dominate effect for GO coagulation than anions. Hydrogen bonds and electrostatic interaction were the main coagulation mechanisms for GO coagulation, which were evidenced by FT-IR and XPS analysis. Specifically, for the first time, the reclaimed product of CA-LDH after GO coagulation (CA-LDH + GO) was applied as adsorbents for the secondary application in the removal of heavy metal ions from aqueous solutions. Interestingly, the CA-LDH + GO still had high adsorption capacities, i.e., the maximum adsorption capacities (qmax) for Cu(II), Pb(II), and Cr(VI) were 122.7 mg/g, 221.2 mg/g and 64.4 mg/g, respectively, higher than other similar materials. This paper highlighted the LDH-based nanomaterials are promising materials for the elimination of environmental pollutants and the migration and transformation of carbon nanomaterials in the natural environment.

Uptake of chloride and carbonate by Mg-Al and Ca-Al layered double hydroxides in simulated pore solutions of alkali-activated slag cement

Chloride ingress and carbonation are major causes of degradation of reinforced concrete. To enable prediction of chloride ingress, and thus to improve the durability of structural alkali-activated slag cement (AAS) based concretes, it is necessary to understand the ionic interactions taking place between chlorides, carbonates, and the individual solid phases which comprise AAS. This study focused on two layered double hydroxides (LDH) representing those typically identified as reaction products in AAS: an Mg-Al hydrotalcite-like phase, and an AFm structure (strätlingite), in simulated AAS pore solutions. Surface adsorption and interlayer ion-exchange of chlorides occurred in both LDH phases; however, chloride uptake in hydrotalcite-group structures is governed by surface adsorption, while strätlingite shows the formation of a hydrocalumite-like phase and ion exchange. For both Ca-Al and Mg-Al LDHs, decreased chloride uptakes were observed from solutions with increased [CO32−]/[OH−] ratios, due to the formation of carbonate-containing hydrotalcite and decomposition of AFm phases, respectively.

Evidence of Multiple Sorption Modes in Layered Double Hydroxides Using Mo As Structural Probe.

Layered double hydroxides (LDHs) have been considered as effective phases for the remediation of aquatic environments, to remove anionic contaminants mainly through anion exchange mechanisms. Here, a combination of batch isotherm experiments and X-ray techniques was used to examine molybdate (MoO42-) sorption mechanisms on CaAl LDHs with increasing loadings of molybdate. Advanced modeling of aqueous data shows that the sorption isotherm can be interpreted by three retention mechanisms, including two types of edge sites complexes, interlayer anion exchange, and CaMoO4 precipitation. Meanwhile, Mo geometry evolves from tetrahedral to octahedral on the edge, and back to tetrahedral coordination at higher Mo loadings, indicated by Mo K-edge X-ray absorption spectra. Moreover, an anion exchange process on both CaAl LDHs was followed by in situ time-resolved synchrotron-based X-ray diffraction, remarkably agreeing with the sorption isotherm. This detailed molecular view shows that different uptake mechanisms-edge sorption, interfacial dissolution-reprecipitation-are at play and control anion uptake under environmentally relevant conditions, which is contrast to the classical view of anion exchange as the primary retention mechanism. This work puts all these mechanisms in perspective, offering a new insight into the complex interplay of anion uptake mechanisms by LDH phases, by using changes in Mo geometry as powerful molecular-scale probe.

Borate-containing layered double hydroxide composites: synthesis, characterization and application as catalysts in the Beckmann rearrangement reaction of cyclohexanone oxime

Boron-containing CaAl-layered double hydroxides (LDHs) were prepared by milling, as well as the dehydration–rehydration and the anion-exchange methods. The substances obtained were structurally characterized by powder X-ray diffraction measurements, scanning electron microscopy and infrared spectroscopy. Various borate species could be introduced among the layers and/or the outer surface of the CaAl-LDH. The materials were tested as catalysts in the Beckmann rearrangement of cyclohexanone oxime to e-caprolactam in the liquid phase, at 373 K. Two of them, the samples prepared by dehydration–rehydration and anion exchange, proved to be active, selective and recyclable catalysts, while the one made by the mechanochemical method was practically inactive. The catalytic activity was tied to intercalated and/or surface-bonded triborate and tetraborate species.

Synthesis and Adsorption Properties of Ca-Al Layered Double Hydroxides for the Removal of Aqueous Fluoride

Ca-Al layered double hydroxides (LDHs) with different Ca/Al molar ratios were composited at pH ranges, using a co-precipitation method, and were experimented to remove fluoride from wastewater and studied in terms of isotherm models such as Langmuir and Freundlich reactions. The composite LDHs were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA). The results showed that different synthesis conditions of Ca-Al LDHs had an influence on their morphology, layered structure, and particle size distribution, which substantially affected the uptake capacity for aqueous fluoride. LDHs with the Ca/Al molar ratio of 2 and synthesized at the pH of 12 had the highest capacity for the fluoride removal (e.g., 146.6 mg/g) and such reaction reached an equilibrium within 1 h. The Freundlich model was a better fit for this study. The high adsorption method of Ca-Al LDHs can be favorable to removing fluoride from wastewater streams.

Study on structure and fluorescence of Tb-doped CaAl LDHs prepared in ethanol/water system

An important material applied in biological fluorescent detector and medical treatment is highly desired in view of the biocompatibility and fluorescent property. Here, Tb-doped CaAl-layered double hydroxides with Ca2+/(Al3+ + Tb3+) molar ratio of 1.0, 2.0, 3.0, and 4.0 have been successfully prepared in a mixed solution of ethanol and water in a reasonable proportion. Chemical compositional analyses revealed that the experimental value of Ca2+/(Al3+ + Tb3+) molar ratio present in the samples was close to the initial value of Ca2+/(Al3+ + Tb3+) molar ratio of raw reactants. In the X-ray diffraction results, it was found that the typical layered double hydroxides structure can be kept between the Ca2+/(Al3++Tb3+) molar ratio of 1.0 and 4.0. The structural type of the Tb-doped CaAl-layered double hydroxides was monoclinic form when the Tb content was less than of 3.0 %, while rhombohedral form appeared and retained as the content of Tb3+ is kept between 3.0 and 5.28 wt%. Photoluminescence shows strong green emissions attributed to 5D4-7FJ (J = 3, 4, 5, 6) transition of Tb3+ ions incorporated in the Tb-doped CaAl-layered double hydroxides. A series of Tb-doped CaAl-LDHs with different molar ratio of Ca2+/(Al3+ + Tb3+) have been synthesized by co-precipitation in a mixed ethanol/water system. Strong green emission appeared in the Tb-doped CaAl-LDH. The Tb–CaAl-LDHs may be a promising biological fluorescent material because of the biocompatibility of Ca2+ ions as well as the fluorescent property of Tb3+ ions.

CaAl-layered double hydroxides as active catalysts for the transesterification of glycerol to glycerol carbonate

Several hydrocalumite-type materials (CaAl-LDHs) were prepared by precipitation using nitrate or chloride salts with and without ultrasound, and aged hydrothermally in autoclave or by refluxing with and without microwaves. These samples were tested as catalysts for the transesterification of glycerol with dimethyl carbonate to glycerol carbonate. After 3h of reaction, all catalysts showed high glycerol conversion (70–84%) and moderate selectivity values to glycerol carbonate (52–65%) accompanied by the formation of low amounts of glycidol (7–15%). These results are very interesting taking into account the low specific surface area of these catalysts (7–25m2/g). No significant catalytic differences were observed between the catalysts. This can be due to the similar surface and basic characteristics observed for all of them. By increasing the reaction time, an increase of conversion was observed arriving practically to total conversion after 24h of reaction, with selectivity to glycerol carbonate in the range 65–75%. Several catalytic reuses favoured the decarboxylation of glycerol carbonate resulting in the formation of higher amounts of glycidol (30%) but still maintaining high selectivity values to glycerol carbonate (70%).

Ultrasonically-enhanced mechanochemical synthesis of CaAl-layered double hydroxides intercalated by a variety of inorganic anions

CaAl-layered double hydroxides (CaAl-LDHs) were synthesised with various interlayer anions (CO32−, F−, Cl−, Br− and I−) by mechanochemical pre-treatment followed by ultrasonic irradiation in aqueous media. The parameters of the syntheses (duration of pre-milling and sonication, quality of the aqueous media, temperature) were altered in order to optimise the procedure and to understand the formation of LDH and other secondary products. The products were characterised by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The optimisation resulted in close-to-phase-pure CaAl-LDHs, not only with carbonate and chloride interlayer anions, but the hard-to-intercalate bromide and iodide as well.

Ultrasound-assisted reconstruction and delamination studies on CaAl layered double hydroxides

Two kinds of CaAl layered double hydroxides (CaAl-LDHs) were synthesized with chloride and nitrate anions by co-precipitation method. The samples were calcined and finally reconstructed by rehydration using ultrasounds, in the presence of NaCl or NaNO3. Reconstructed samples presented smaller lamella size than the parent ones. All samples were characterized by X-ray powder diffraction, FT-IR spectroscopy, thermogravimetric analysis and TEM microscopy. Delamination was not achieved by mechanical stirring for 2days, whereas most samples underwent delamination by the use of ultrasounds. Additionally, a hybrid CaAl-LDHs with CdTe quantum dots was synthesized by reconstruction of a calcined CaAl-LDHs in the presence of the quantum dots.

Copper, lead and cadmium removal by Ca Al layered double hydroxides

Layered double hydroxides are increasingly studied as heavy metal scavengers due to their acid/base buffering capacity that leads to hydroxide precipitation. Their intercalation with ligands such as edta also provides active sites for heavy metal chelation to these solids. In this work, both mechanisms are studied in Ca–Al layered double hydroxides (LDHs) with a Friedel's salt layered structure and intercalated with either nitrate (Ca–Al–NO3) or [Ca(edta)]2− (Ca–Al–[Ca(edta)]). With this aim, the acid–base buffering capacity of these solids was determined and their removal behavior studied as a function of equilibrium concentration and pH. The solids presented high instability, Ca2+ ions being selectively leached at pH values as high as 8. As a consequence, high affinity and large removal capacity of Cu2+, Cd2+ and Pb2+ were obtained for Ca–Al–NO3 by a hydroxide precipitation mechanism. The removal capacity of Ca–Al–[Ca(edta)] was quite similar, however, a portion of heavy metal ions was solubilized due to [Ca(edta)]2− release. The heavy metal hydroxides obtained by the Ca–Al LDH removal action produced immobilization at pH values lower than those produced by simple alkalinization.

Synthesis and properties of CaAl-layered double hydroxides of hydrocalumite-type

AbstractCaAl-layered double hydroxides (CaAl-LDHs) with various carbonate ion contents are essentially formed in Bayer liquors during the causticisation step in alumina production. Under well-defined conditions hemicarbonate is formed, which is beneficial in the process of retrieving both Al(OH)4− and OH− ions. In the current work, Ca2Al-LDHs with various carbonate contents were prepared by the co-precipitation procedure and the products were dried in different ways. Structural information was obtained by a variety of methods, such as X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Elemental maps were constructed through a combination of SEM images and EDX measurements. The targeted CaAl-hydrocalumites were successfully synthesised. It was found that the method used for drying did not influence the basal spacing although it significantly altered the particle sizes.

The role of dispersion of LDH in fire retardancy: The effect of different divalent metals in benzoic acid modified LDH on dispersion and fire retardant properties of polystyrene– and poly(methyl-methacrylate)–LDH–B nanocomposites

The influence of three different divalent metals, calcium, magnesium and zinc, using benzoate-modified layered double hydroxides (LDHs), on the dispersion and fire properties of polystyrene (PS) and poly(methyl-methacrylate) (PMMA) is investigated. PS- and PMMA-layered double hydroxide (PS/LDHs PMMA/LDHs) nanocomposites are prepared by in situ bulk polymerization in the presence of the benzoate-modified LDHs. The morphology of the nanocomposites is characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD results indicate that the characteristic layered structure of Ca–Al–LDH–B completely disappear in both polymers, whereas for Zn–Al–LDH–B and Mg–Al–LDH–B that is not the case. TEM confirms excellent dispersion and exceptional distribution of exfoliated Ca–Al–LDH–B within both polymer matrices, while for Zn–Al–LDH–B and Mg–Al–LDH–B dispersion is poorer with more tactoids present. Thermal stability and fire properties are investigated by thermogravimetric analysis (TGA) and cone calorimetry (CC). All PMMA nanocomposites show enhanced thermal stability compared to neat PMMA, while thermal stability of PS is enhanced only by the addition of Ca–Al–LDH–B. PS/Ca–Al–LDH–B and PS/Zn–Al–LDH–B systems show better fire properties compared to the PS/Mg–Al–LDH–B; peak heat release rate reduction is 42 and 41%, respectively, vs. only 15% for the PS/Mg–Al–LDH–B at 10% LDH loading. The largest peak heat release rate reduction (PHRR), 52%, is measured for the PMMA/Mg–Al–LDH–B nanocomposites at 10% LDH loading, although dispersion is very poor. PHRR reduction of the PMMA/Ca–Al–LDH–B nanocomposites at 10% LDH loading is 45%, while 30% reduction of the PHRR is measured for nanocomposites containing 10% Zn–Al–LDH–B.

CO2 Sorbents with Scaffold‐like CaAl Layered Double Hydroxides as Precursors for CO2 Capture at High Temperatures

A highly stable high-temperature CO₂ sorbent consisting of scaffold-like Ca-rich oxides (Ca-Al-O) with rapid absorption kinetics and a high capacity is described. The Ca-rich oxides were prepared by annealing Ca-Al-NO₃ layered double hydroxide (LDH) precursors through a sol-gel process with Al(O(i)P)₃ and Ca(NO₃)₂ with Ca(2+)/Al(3+) ratios of 1:1, 2:1, 4:1, and 7:1. XRD indicated that only LDH powders were formed for Ca(2+)/Al(3+) ratios of 2:1. However, both LDH and Ca(OH)₂ phases were produced at higher ratios. Both TEM and SEM observations indicated that the Ca-Al-NO₃ LDHs displayed a scaffold-like porous structure morphology rather than platelet-like particles. Upon annealing at 600 °C, a highly stable porous network structure of the CaO-based Ca-Al-O mixed oxide (CAMO), composed of CaO and Ca₁₂Al₁₄O₃₃, was still present. The CAMO exhibited high specific surface areas (up to 191 m(2)g(-1)) and a pore size distribution of 3-6 nm, which allowed rapid diffusion of CO₂ into the interior of the material, inducing fast carbonation/calcination and enhancing the sintering-resistant nature over multiple carbonation/calcination cycles for CO₂ absorption at 700 °C. Thermogravimetric analysis results indicated that a CO₂ capture capacity of approximately 49 wt% could be obtained with rapid absorption from the porous 7:1 CAMO sorbents by carbonation at 700 °C for 5 min. Also, 94-98% of the initial CO₂ capture capability was retained after 50 cycles of multiple carbonation/calcination tests. Therefore, the CAMO framework is a good isolator for preventing the aggregation of CaO particles, and it is suitable for long-term cyclic operation in high-temperature environments.

In situ grown of nano-hydroxyapatite on magnetic CaAl-layered double hydroxides and its application in uranium removal

This paper report on the efficient removal of uranium ions from aqueous solution with a novel magnetic composite adsorbent, calcined magnetic layered double hydroxide/hydroxyapatite (CMLH). This adsorbent was obtained via in situ grown of nano-hydroxyapatite on magnetic CaAl-layered double hydroxides and followed with calcining. The morphology and microstructure of the as-prepared adsorbents were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. The influences of conditions for uranium removal, including dosage of LDHs, pH of aqueous solution, and temperature on anion-exchange have been investigated, respectively. The thermodynamic parameters including Gibbs free energy (ΔG0), standard enthalpy change (ΔH0) and standard entropy change (ΔS0) for the process were calculated using the Langmuir constants. It was found from kinetics test that the pseudo-second order kinetics model could be used to well describe the uptake process. Furthermore, the CMLH could be regenerated through the desorption of the uranium using 0.5M NaHCO3 solution and could be reused to adsorb after calcination.

Facile preparation of pure CaAl-layered double hydroxides and their application as a hardening accelerator in concrete

CaAl-layered double hydroxide (CaAl-LDH), one of anionic functional layered materials, has recently been proposed as potential concrete hardening accelerators. Previous laboratory synthesis shows the necessity of employing a protective nitrogen atmosphere to avoid the formation of large amounts of CaCO 3 byproduct. Here, we present a preparation of pure CaAl-LDHs which are readily free of contamination by CaCO 3. The CaAl-LDHs were prepared via a scalable method of separate nucleation and aging steps (SNAS) by facile introduction of a mixed ethanol/water media. The application of the as-prepared CaAl-LDHs was investigated as a hardening accelerator in concrete. Standard tests of the compressive and flexural strengths of the cement mortars showed that specimens containing CaAl-LDHs as a hardening accelerator exhibited a greatly enhanced performance in respect of early compressive strength and early flexural strength; and the values increased by 61% and 71%, respectively compared to the pristine concrete specimen. The enhanced performances were addressed in terms of the results in situ X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry.