Ion Concentration In Solution Research Articles

Removal of copper ions from industrial wastewater using waste from iron and magnesium production

Research objective is to assess the possibility of removing copper ions from industrial wastewater using waste from iron and magnesium production. Methods of research. An experiment was conducted to remove copper ions from a solution of industrial wastewater using waste from iron and magnesium production. Data were obtained showing changes in the ion content of the studied metals in wastewater solutions. Theoretical research was carried out to analyze the effectiveness of existing wastewater treatment methods in order to study and generalize the results. The initial concentration of metal ions in solutions was measured with a Varian AA 240 FS atomic absorption spectrophotometer with a deuterium lamp for background correction and flame spraying. Temperature and pH were measured with a Hanna HI 99121 portable pH meter. Mineralization of solid samples was carried out with a MARS 5 Digestion Microwave System in Easy Prep vessels with the addition of nitric and hydrofluoric acids. Results. The results of the research on the removal of copper ions from industrial waste water using iron-magnesium production waste show that the samples under investigation were effective in absorbing copper from aqueous solutions. It was found that the amount of copper in the filtrates varies depending on the tested sorbent sample weight. There is an increase in the indicator of the degree of pollutant extraction from solutions from 52.02 to 99.04% for group 1 and from 43.2 to 98.91 % for group to respectively with an increase in the sample dosing rate from 0.2 to 0.5 g. The indicator of static volume capacity also depends on the mass of the sample added to the solution and decreases with the dosing rate growth. Wastes of iron-magnesium production contain magnesium and iron in high concentrations. After interaction with industrial waste water, they actively release magnesium into the solution, but continue to extract iron from it. The indicators of the degree of pollutant extraction from solutions and of static volume capacity for iron have high values regardless of the sample weight for both groups and vary from 99.85 to 99.98% and from 3.9 to 10.82 mg/g. Scope of results. The data obtained will used to develop effective materials and methods for water bodies pollution elimination.

Sorption of ammonium by fibrous sorbent VION KN-1

The results of studies of the sorption extraction of ammonium ions from aqueous media by the fibrous sorbent VION KN-1 are presented. Weak acid ion exchange fiber. It has been established that the limiting step in the process of ammonium ion sorption is internal diffusion. The kinetic parameters of the sorption process are calculated, with the identification of a decrease in the half-sorption time and an increase in the internal diffusion coefficient. The applicability of the Langmuir and Freindlich models for describing the experimental isotherms of ammonium ion sorption by fiber has been studied. Certain constants and parameters. Through the appearance of regression coefficients, R2 showed that the Langmuir model better explores experimental data on the sorption of ammonium ions by a fibrous sorbent. A study of sorption in media was carried out. According to the curves of the dependence of the degree of extraction on the concentration and on the depth of the missed solution, it was found that with a decrease in concentration in the dynamic sorption mechanism, the reduction characteristics do not decrease, which makes their use reduced in the purification of dilute solutions containing ammonium ions. At a low concentration of ammonium ions in the initial solution, the degree of extraction is more than 93%. To predict the extraction of ammonium ions from wastewater, an increased concentration of neural packages of STATISTICA application programs was used. The input parameters for studying the neural network were chosen: the concentration of ammonium ions, the volume of the solution passed through the sorbent layer, and the weight of the sample of fibers. The output parameter is the degree of extraction of ammonium ions. The trained MPL-3-5-1 neural network has high coefficients of determination for the training, test and control samples, which gives a high estimate of the network performance and can predict the degree of extraction of ammonium ions by the fibrous sorbent VION KN-1..

Eco‐Friendly Biosorption of Uranium from Aqueous Solutions Using Sepiolite‐Cavex CA37 Composite Biosorbent

AbstractCavex CA37 is a dental material used for positive tooth impressions. After the mold is taken, it hardens through a fast‐chemical reaction with air, then becomes waste after usage. In this study, natural sepiolite and Cavex CA37 are mixed at certain ratios to obtain a composite SCX‐37 biosorbent that is used for the biosorption of ions from a synthetic aqueous solution. Parameters affecting biosorption, such as solution pH, ambient temperature, contact time, and ion concentration, are investigated. The biosorption of ions on SCX‐37 reaches equilibrium in 120 min with 97.56% efficiency at 30 °C and pH 4. The isotherms (Langmuir, Freundlich, and D‐R) and thermodynamic values of the biosorption of ions on the SCX‐37 biosorbent are calculated according to the obtained data. It is determined that there is a high correlation between experimental results and all three isotherm models. The adsorption capacity is found to be 41.39 mg g−1. The biosorption of ions onto the SCX37 biosorbent is a chemisorption process with an adsorption energy of 40.50 kJ mol−1.

Novel hydrazine hydrate sensor based on”fish-bait” capture mode

ABSTRACT Coordination reaction is a usual way for the concentration of metal ions in aqueous solution. In this work, 5-(5-iodine-2-pyridine azo)-2,2 amie toluene (5-PADAT) was firstly casting onto carbon glass electrode (GCE), play a role of ‘bait’; then, immersed 5-PADAT modified GCE into immersed aqueous solution containing order of magnitude ppm Palladium ions (Pd2+, play a role of ‘fishes’); ‘Fishes’ were captured by ‘bait’ with the reaction process of 5-PADAT and Pd2+, leading to the concentration of Pd2+ onto the GCE; Cyclic voltammetry was employed to reduce Pd2+ in situ, formed Pd nanoparticles (PdNPs) modified GCE. It can be used to detect the oxidation of hydrazine hydrate at a very low potential, 0.1 V.

Reuse of waste cooking oil (WCO) as diluent in green emulsion liquid membrane (GELM) for zinc extraction.

Zinc (Zn) was identified as one of the most toxic heavy metals and often found contaminating the water sources as a result of inefficient treatment of industrial effluent. A green emulsion liquid membrane (GELM) was proposed in this study as a method to minimize the concentration of Zn ions in an aqueous solution. Instead of the common petroleum-based diluent, the emulsion is reformulated with untreated waste cooking oil (WCO) collected from the food industry as a sustainable and cheaper diluent. It also includes Bis(2-ethylhexyl) phosphate (D2EHPA) as a carrier, Span 80 as a surfactant, sulfuric acid (H2SO4) as an internal phase, and ZnSO4 solution as an external phase. Such formulation requires a thorough understanding of the oil characteristics as well as the interaction of the components in the membrane phase. The compatibility of WCO and D2EHPA, as well as the external phase pH, was confirmed via a liquid-liquid extraction (LLE) method. To obtain the best operating conditions for Zn extraction using GELM, the extraction time and speed, carrier, surfactant and internal phase concentrations, and W/O ratio were varied. 95.17% of Zn ions were removed under the following conditions; 0.001M of H2SO4 in external phase, 700rpm extraction speed for 10min, 8 wt% of carrier and 4 wt% of surfactant concentrations, 1:4 of W/O ratio, and 1M of internal phase concentration.

Solution Structure and Hydration Forces between Mica and Hydrophilic Versus Hydrophobic Surfaces

Solid–liquid interfaces are central to a range of interesting phenomena including colloidal aggregation, crystallization by particle attachment, catalysis, heterogeneous nucleation, water desalination, and biomolecular assembly. While three-dimensional atomic force microscopy (3D AFM) has emerged as a technique for resolving interfacial solution structure at the molecular scale, key challenges for data interpretation persist, most notably regarding the influence of the probe on the measured structure. Using the mica–water system as a case study, we investigate the effect of hydrophilic and hydrophobic probes on interfacial solution structure measured by 3D AFM. Data from hydrophilic silicon-based probes are in good agreement with molecular dynamics simulations, wherein the innermost water molecules adsorb preferentially at the surface ditrigonal cavity sites, followed by two additional ordered hydration layers. In contrast, the hydrophobic carbon-based probes detect vertical oscillatory features but do not show lateral patterning that matches the underlying mica lattice. At high ionic strength, up to six of these oscillatory features are observed extending 2 nm into the solution phase with an average spacing of 0.29 ± (0.04) nm. We also determine that the repulsive hydration force between mica and the hydrophilic probe depends on the nature and concentration of ions in solution. Specifically, solutions with stronger ion–water and ion–ion interactions produce a stronger repulsive hydration force as the probe approaches the surface. Based on these observations, we present a scheme for controlling the outcomes of particle aggregation and attachment by varying the solution conditions to tune the hydration force.

Agro-Ecological Impact of Irrigation and Nutrient Management on Spinach (Spinacia oleracea L.) Grown in Semi-Arid Conditions

The environment is affected by most anthropogenic activities; among them, agriculture is one activity with more negative effects, especially when management is inadequate, causing soil degradation or contamination. This paper presents the results of an agronomic field trial on a spinach (Spinacia oleracea L.) crop. The objective of which was to monitor soil and crop properties under two doses of irrigation and organic fertilization. The results showed that the use of excessive doses of irrigation and fertilization increased the electrical conductivity (ECext) from 5.5 to 8.5 dS m−1 and the concentration of ions in the soil solution which, for the most soluble ions (NO3−, Cl−, Na+), leached towards the deep horizons, reaching 2194.8 mg L−1 in the case of NO3−. However, their use did not increase spinach production and is thus a waste of resources that increases the risk of soil salinization. Nutrient inputs to the soil were much higher than extractions (between 12% for N and 99% for Fe), partly because of agronomic management and especially because of the return of crop residues, which increased the organic carbon stock by about 2500 kg ha−1 (4–6%), enhancing its function as a CO2 sink. These surpluses form part of complex organic structures or are immobilized as carbonates or alkaline phosphates. Preservation of the agrosystem studied requires limiting the use of low-quality irrigation water and adjusting fertilization.

Investigation on the Removal Performances of Heavy Metal Copper (II) Ions from Aqueous Solutions Using Hydrate-Based Method.

Since heavy metal ion-contaminated water pollutionis becoming a serious threat to human and aquatic lives, new methods for highly efficient removal of heavy metal ions from wastewater are important to tackle environmental problems and sustainable development. In this work, we investigate the removal performances of heavy metal copper (II) ions from aqueous solutions using a gas hydrate-based method. Efficient removal of heavy metal copper (II) ions from wastewater via a methane hydrate process was demonstrated. The influence of the temperature, hydration time, copper (II) ions concentration, and stirring rate on the removal of heavy metal copper (II) ions were evaluated. The results suggested that a maximum of 75.8% copper (II) ions were removed from aqueous solution and obtained melted water with 70.6% yield with a temperature of -2 °C, stirring speed 800 r/min, and hydration time of 4 h with aninitial copper concentration of 100 mg/L. The initial concentration of copper (II) ions in the aqueous solution could be increased to between 100 and 500 mg/L. Meanwhile, our study also indicated that 65.6% copper (II) ions were removed from aqueous solution and the yield of melted water with 56.7%, even with the initial copper concentration of 500 mg/L. This research work demonstrates great potential for general applicability to heavy metal ion-contaminated wastewater treatment and provides a reference for the application of the gas hydrate method in separation.

Use of copper carbonate as corrosion inhibitor for carbon steel in post combustion carbon capture

The realisation of post-combustion CO2 capture (PCCC) at industrial scale remains limited; one challenge is the concerns around capital costs and another concern is corrosion of the system itself. Corrosion resistance and mitigation against the amine solvent monoethanolamine (MEA) was studied, using the inhibitor copper (II) carbonate basic (CC). Carbon steel (C1018) was tested in CO2 loaded, 5M aqueous MEA solution, alone and in the presence of CC, to assess the corrosivity of the solution. Immersion testing used mass loss, Fe and Cu ion concentration in solution via ICP-MS, imaging (SEM) and analytical techniques (XRD and EDX) to investigate the effect of corrosion. Generally, the use of CC improved C1018 corrosion resistance relative to C1018 alone. Even at low concentrations (0.9 mM), CC was effective in inhibiting corrosion against CO2 loaded MEA, as the observed corrosion rate was effectively zero and no dissolved Fe was detected in solution. There was no evidence of copper surface adsorption. To clarify the solution chemistry resulting in corrosion inhibition, the local chemical environment of Fe and Cu were probed by Cu and Fe K-edge X-ray Absorption Spectroscopy, respectively. The Cu K- edge HERFD-XANES spectra reveal that a Cu2+ amine complex forms, critical to understanding the structure which is promoting significant corrosion inhibition.

Environmentally Friendly Strategy for Treating In Situ Leaching Solutions of Ion-Adsorption Type Yttrium-Rich Heavy Rare-Earth Ore by a Bubble-Supported Organic Liquid Membrane

A novel environmentally friendly strategy based upon bubble-supported organic liquid membrane (BSOLM) extraction using saponified naphthenic acid as extractant is proposed in the present work for treating the in situ leaching solutions of ion-adsorption type yttrium-rich heavy rare-earth ores in South China. It was revealed that selectively preferential separation of non-yttrium rare earths from yttrium can be achieved, while the electrolyte aluminum salt can be retained in the raffinates for subsequent return as the leaching reagent for performing in situ leaching of ion-adsorption type heavy rare-earth ores. The BSOLM extraction exhibits an obvious advantage over conventional extraction in promoting the competitive mass transfer and separation of coexisting rare earths from yttrium and other non-rare-earth impurity ions. Using erbium as a representative of heavy rare earths, it was found that the differences in diffusive mass transfer rate of Er3+, Y3+, and Al3+ ions in the boundary layer of laminar flow near the surface of the extractant liquid membrane result in their enhanced separation. The BSOLM extraction prevents the convective disturbance along the normal vertical direction of the interface due to the irregular movement of dispersed oil droplets in the conventional extraction and therefore inhibit the co-extraction of Al3+ ions. The effects of Al3+ ion concentrations in aqueous feed solutions, initial aqueous pHs, concentrations of naphthenic acid, and its saponification degree on the separation efficiency were investigated. Experimental results confirmed that competitive hydration and adsorption of Al3+ ions at the interface play an important role in increasing the difference in concentration distribution of Er3+ and Y3+ ions near the interface during BSOLM extraction; therefore, the separation of rare earths from yttrium can be controllable.

On-chip on-demand delivery of K+ for in vitro bioelectronics

Bioelectronic devices that interface electronics with biological systems can actuate and control biological processes. The potassium ion plays a vital role in cell membrane physiology, maintaining the cell membrane potential (Vmem) and generating action potentials. In this work, we present two bioelectronic ion pumps that use an electronic signal to modulate the potassium ion concentration in solution. The first ion pump is designed to integrate directly with six-well cell culture plates for optimal ease of integration with in vitro cell culture, and the second on-chip ion pump provides high spatial resolution. These pumps offer increased ease of integration with in vitro systems and demonstrate K+ concentration distribution with high spatial resolution. We systematically investigate the ion pump’s performance using electrical characterization and computational modeling, and we explore closed-loop control of K+ concentration using fluorescent dyes as indicators. As a proof-of-concept, we study the effects of modulating K+ concentration on Vmem of THP-1 macrophages.

Removal of cobalt (II) by dithizone-immobilized nickel slag

In this study, activated nickel slag waste was modified with dithizone to remove Co(II) metal ions inthe water. Dithizone was confirmed to have successfully beenimmobilized on anactivated nickel slag using SEM-EDX (Scanning Electron Microscopy-Energy Dispersive X-ray), FTIR (Fourier-Transform Infrared Spectroscopy), and XRD (X-ray Diffraction). Studies on the adsorption of Co(II) metal ions in water were conducted by varying the solution's pH, adsorption mass, contact time, and Co(II) ion solution concentration. The findings revealed that the optimumpH conditions for adsorption occurred at pH 5 for 120 min and the adsorption kinetics followed a pseudo-second-order kinetics model. Meanwhile, the Langmuir isotherm model was used for Co(II) ion adsorption. The desorption study revealed that ion exchange interactions dominate activated nickel slag while hydrogen bonding and electrostatic interactions dominate nickel slag immobilized with dithizone.

ДОСЛІДЖЕННЯ КОМПЛЕКСОУТВОРЕННЯ ПОЛІЕТИЛЕНІМІНУ З ЙОНАМИ МІДІ (ІІ), НІКЕЛЮ (ІІ), КОБАЛЬТУ (ІІ)

There is described the influence of polyethylenimine globule structure on complexation with copper (II), nickel (II) and cobalt (II) ions. There are determined the values of the coordination number with the change of the pH of the solution for the complexes of ethylenediamine, diethylenetriamine and polyethylenimine with metal ions. It is investigated that the complexation of these metal ions with low molecular weight amines passes through three stages and with PEI through two stages. It is shown that the content of free nitrogen atoms in PEI, which do not react with metal ions, increases with increasing concentration of PEI in solution. The number of monomer units associated with metal ions depends on the size of the globule of the macromolecule, as well as the reaction process. The complexation reaction in solution is determined by the diffusion of metal ions into the polymer globule. If the reaction takes place in a diffusion field at a low polymer concentration, the rate of complexation is proportional to the concentration of macromolecules and the concentration of metal ions in solution.

Prospective of the LDI MS to characterization the corrosion products of silver-copper alloys on an example of the Ag-Cu-X (X- Zn, Pd, In) system

This work presents the perspective of applying the laser desorption/ionization mass spectrometry (LDI MS) for characterization the anode film of the Ag60Cu26Zn14, Ag58.5Cu31.5Pd10, and Ag63Cu27In10 alloys (at high concentrations of chloride ions in solutions). The reference LDI mass spectra of anode films of pure Ag and Cu have been used for the identification of product corrosion. Knowing the clusters detected in the reference spectra lead to the facilitating identification of the LDI mass spectrum of the sample and reduces the analysis time. The LDI MS analysis of these alloys revealed that the predominant corrosion product are AgCl (from AgnCln+1−/+, n = 1–3), and CuCl (from “superhalogen” CumCln− clusters, m = 1–2, n = 2–6); it also revealed Cu2(OH)3Cl (from Cu2(OH)(H2O)2+) and Cu2O (from Cu(H2O)+, Cu2O doped with chlorine). These results are in accordance with the X-ray diffraction and Raman analysis. The LDI MS spectra of alloys contain the additional peaks formed due to the mutual influences of different metals in the alloys (AgCuCl3− (AgCl-CuCl2−), AgCu2Cl4− (AgCl-CuCl-CuCl2−), and Ag2CuCl4− (AgCl-AgCl-CuCl−), which is consistent with the identified corrosion products. It should be noted that the LDI MS suggest the presence of CuCl2, which can be interpreted as the corrosion products retained in the porous films of alloys, and not detected by the other methods due to a small amount. The future theoretical and experimental studies of metal clusters, significant for metallurgy, can contribute that the LDI MS is becoming a powerful analytical tool for characterization the metal surfaces.

Construction of hierarchical and porous cellulosic wood with high mechanical strength towards directional Evaporation-driven electrical generation

Tremendous efforts have been dedicated to harvesting energy from the ubiquitous natural water evaporation process. Inspired by the plant's bioelectric phenomenon during the transport of sap from bottom to top, the hierarchically porous cellulosic wood was engineered as the robust carrier for efficiently capturing and transferring water and moisture by removing lignin and hemicellulose, releasing the microscale pore in the cell wall and nanoscale pores in the middle lamella. A conductive polymer, poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS), was impregnated in the cellulosic wood, which was further lyophilized to increase the specific surface area and improve the charge transport as an evaporation-driven electrical generator (EEG) with high Young’s modulus. This EEG produces a sustained voltage of around 385 mV and current over 11 μA across the porous and conductive cellulosic wood in a saturated NaCl solution. The anisotropic nature of the cellulosic wood leads to a higher output voltage in the growth direction than in the transverse direction. The driving force behind this energy generation is a self-maintained moisture gradient to generate an ion concentration difference between the output electrodes when the system is exposed to water or moisture. Furthermore, the critical factor of energy generation is the coupling between naturally aligned cellulose microfibrils in wood and water molecule. The generated voltage could be increased by elevating the concentration of ions in the aqueous solution and the temperature difference between the output electrodes. These strong and hierarchical cellulosic wood have a significant potential for electric energy collection through water evaporation and waste heat energy.

Selective Sorption of Silver Ions from Aqueous Solutions Using Poly(N-thiocarbamoyl‑ 3-aminopropylsilsesquioxane)

The accumulation of electronic waste (e-waste) on the ground leads to environmental pollution with toxic metal ions, which subsequently harms all living organisms. Many countries still use hydrometallurgical or manual methods to extract silver ions from e-waste. These methods are unsustainable and highly toxic; therefore, it becomes necessary to introduce new environmentally compatible methods for separating valuable components from objects of various compositions. This article proposes an environmentally compatible method for the extraction of silver ions from multicomponent systems using poly(N-thiocarbamoyl‑3-aminopropylsilsesquioxane). The sorbent surface was studied by Fourier-transform infrared spectroscopy using an attenuated total internal reflection accessory. The concentration of grafted thiourea groups is 1.39 mmol/g according to elemental analysis. It has been determined that this sorbent is capable of quantitatively extracting silver ions in the pH range from 0 to 6 at a concentration of silver ions in the initial solution of 1·10–4 mol/dm3; the static sorption capacity for silver ions under experimental conditions reaches 1.22 mmol/g. When sorption is carried out in dynamic mode, the value of the dynamic capacity before breakthrough is 0.046 mmol/g, and the value of the total dynamic capacity for silver ions is 0.132 mmol/g. The highest desorption (71–78 %) is achieved using sulfuric acid solutions with a thiourea concentration gradient.

Effects of sodium aluminate and reverse osmosis brine on hydration and mechanical properties of slag

In this study, reverse osmosis brine (ROB) and sodium aluminate (NA) were used as mix water and an activator for ground granulated blast furnace slag (GGBFS), respectively, to investigate the hydration reaction and mechanical properties of the GGBFS. Samples with NA alone and a combination of NA and 5% and 10% CaO were fabricated using tap water (TW) and ROB as mix water. The addition of CaO enhanced the effect of the NA activator in increasing the strength of the samples. With the NA–CaO combination, TW samples promoted the formation of C2ASH8 and C3AH6 phases more than the ROB samples. In the ROB samples, Friedel’s salt was formed. The strength of the TW samples was lower than that of the ROB samples, attributed to the abundantly formed C3AH6 phase in the TW samples. The NA–CaO–ROB samples improved the chloride ion adsorption capacity by increasing the Ca/Si ratio of the hydration reactant. However, in the ROB samples, Friedel's salt was decomposed due to carbonation by air exposure, increasing the concentration of chloride ions in the pore solution and promoting calcite formation. The NA–CaO–ROB samples confirmed the effectiveness of NA as a new GGBFS activator and the potential of ROB as a building material.

Phosphate-Trapping Liposomes for Long-Term Management of Hyperphosphatemia.

Hyperphosphatemia is a typical complication of end-stage renal disease, characterized by elevated and life-threatening serum phosphate levels. Hemodialysis does not enable sufficient clearance of phosphate, due to slow cell-to-plasma kinetics of phosphate ions; moreover, dietary restrictions and conventional treatment with oral phosphate binders have low success rates, together with adverse effects. Here, we developed a new concept of phosphate-trapping liposomes, to improve and prolong the control over serum phosphate levels. We designed liposomes modified with polyethylene glycol and encapsulated with the phosphate binder ferric citrate (FC liposomes). These liposomes were found to trap phosphate ions in their inner core, and thereby lower free phosphate ion concentrations in solution and in serum. The FC liposomes showed higher phosphate binding ability as phosphate concentrations increased. Moreover, these liposomes showed a time-dependent increase in uptake of phosphate, up to 25 h in serum. Thus, our findings demonstrate effective long-term phosphate trapping by FC liposomes, indicating their potential to reduce serum phosphate toxicity and improve current management of hyperphosphatemia.

Effect of brick powder on the pore solution and microstructure of Portland cement

In order to investigate the effect of brick powder on the pore solution and microstructure of Portland cement, the pH value, ion concentration and electrical conductivity of the pore solution were explored, and the pore structure and morphology of cementitious materials was explored by Mercury intrusion porosimetry (MIP) and scanning electron microscope (SEM) in this study. The results indicated that the addition of brick powder decreases the pH value of the pore solution and also has an impact on the ion concentration of the pore solution. The pozzolanic reaction at the late hydration stage consumes Ca2+ and decreases the pH value. And the pozzolanic reaction products fill pore and refine the pore size, in addition, brick powder also has filler effect and dilution effect. The addition of brick powder reduces the aspect ratio of ettringite.

Comparison on early hydration of Portland cement and sulphoaluminate cement in the presence of nano ettringite

This paper proposed adopting ettringite-based nucleation seeds to induce ettringite to precipitate in the pore solution, and thus facilitated early hydration reaction. In present work, sulphoaluminate cement (SAC) and Portland cement (PC) paste were considered, and 0 ∼ 5 % nano-ettringite prepared by hydration-wet grinding method was extra incorporated. The hydration kinetic of the blends was studied by hydration heat, chemical shrinkage and setting time. The effects of nano-ettringite on the dissolution behavior were also examined by dynamic conductivity of cement slurry, ion concentration and conductivity of pore solution. Meanwhile, the hydrate assemblage was determined by XRD, TGA, FTIR and 27Al NMR, and the compressive strength was also tested. On this basis, the hydration mechanism was discussed. Results indicated that nano-ettringite significantly hastened ions dissolution and ettringite precipitation, whether it was SAC or PC paste. The initial hydration heat release and chemical shrinkage were obviously promoted, and even cracks were generated in SAC paste; besides, the setting time was also shortened dramatically. In the presence of 1 ∼ 5 % nano-ettringite, the compressive strength of PC pastes at 8 h was increased by 54 ∼ 180 %. However, the strength of SAC paste at all ages was degraded by adding nano-ettringite, due to the appearance of cracks and reduced amount of AH3.