Bulk modulus of basic sodalite, Na8[AlSiO4]6(OH)2·2H2O, a possible zeolitic precursor in coal-fly-ash-based geopolymers

Synthetic basic sodalite, Na₈[AlSiO₄]₆(OH)₂·2H₂O, cubic, P43n, (also known as hydroxysodalite hydrate) was prepared by the alkaline activation of amorphous aluminosilicate glass, obtained from the phase separation of Class F fly ash. The sample was subjected to a process similar to geopolymerization, using high concentrations of a NaOH solution at 90 °C for 24 hours. Basic sodalite was chosen as a representative analogue of the zeolite precursor existing in Na-based Class F fly ash geopolymers. To determine its bulk modulus, high-pressure synchrotron X-ray powder diffraction was applied using a diamond anvil cell (DAC) up to a pressure of 4.5 GPa. A curve-fit with a truncated third-order Birch–Murnaghan equation of state with a fixed K'_o = 4 to pressure-normalized volume data yielded the isothermal bulk modulus, K_o = 43 ± 4 GPa, indicating that basic sodalite is more compressible than sodalite, possibly due to a difference in interactions between the framework host and the guest molecules.     

Calcium Sulfoaluminate Sodalite (Ca4Al6O12SO4) Crystal Structure Evaluation and Bulk Modulus Determination

The predominant phase of calcium sulfoaluminate cement, Ca₄(Al₆O₁₂)SO₄, was investigated using high‐pressure synchrotron X‐ray diffraction from ambient pressure to 4.75 GPa. A critical review of the crystal structure of Ca₄(Al₆O₁₂)SO₄ is presented. Rietveld refinements showed the orthorhombic crystal structure to best match the observed peak intensities and positions for pure Ca₄(Al₆O₁₂)SO₄. The compressibility of Ca₄(Al₆O₁₂)SO₄ was studied using cubic, orthorhombic, and tetragonal crystal structures due to the lack of consensus on the actual space group, and all three models provided similar results of 69(6) GPa. With its divalent cage ions, the bulk modulus of Ca₄(Al₆O₁₂)SO₄ is higher than other sodalites with monovalent cage ions, such as Na₈(AlSiO₄)₆Cl₂ or Na₈(AlSiO₄)₆(OH)₂·H₂O. Likewise, comparing this study to previous ones shows the lattice compressibility of aluminate sodalites decreases with increasing size of the caged ions. Ca₄(Al₆O₁₂)SO₄ is more compressible than other cement clinker phases such as tricalcium aluminate and less compressible than hydrated cement phases such as ettringite and hemicarboaluminate.     

Synthesis and crystal structure of the dimeric,Ti–O–Ti bridged hydrid form polyoxoanion [α-1,2-PW10Ti2O39]210−

The reaction of trivacant precursor Na₉[A–PW₉O₃₄]·19H₂O with Ti(SO₄)₂ affords the novel dimeric, di-Ti^IV-substituted tungstophosphate K₄Na₆[α-1,2-PW₁₀Ti₂O₃₉]₂·14H₂O. The X-ray structural determination shows the dimeric, anhydride structure was formed by two Ti–O–Ti bonds linking two di-titanium-substituted Keggin anion [α-1,2-PW₁₀Ti₂O₄₀]. It was also characterized by elemental analysis, TGA, FT-IR and UV–vis spectroscopies.     

pH-dependent assembly of 1D–2D structures based on both {V10O28} and [NiMo6O24H6]4 − units: Synthesis,structure and magnetic properties

Two novel complexes [H₂N(CH₂CH₂)₂O]₄[Na(H₂O)₂{O(CH₂CH₂)₂NH₂}]₂[Na(H₂O)₄]₂[V₁₀O₂₈][NiMo₆O₂₄H₆]·8H₂O (1) and [H₂N(CH₂CH₂)₂O]₆[Na(H₂O)₃]₂[V₁₀O₂₈H₂][NiMo₆O₂₄H₆]·4H₂O (2) containing both isopolyvanadate {V₁₀O₂₈} and [NiMo₆O₂₄H₆]^4 − units have been synthesized and structurally characterized for the first time, showing that the pH value of the reaction plays a key role in structure control of self-assembled processes. Compound 1 exhibits a novel one-dimensional (1-D) chain-like structure consisting of Anderson-type [NiMo₆O₂₄H₆]^4 − and isopolyvanadate [V₁₀O₂₈]^6 − anions linked by Na⁺ ions. In compound 2 with the lower pH value, [NiMo₆O₂₄H₆]^4 − and [V₁₀O₂₈H₂]^4 − anions are bridged by [Na₂O₁₀] units to form the 2D extended layer. The magnetic properties of 1 and 2 are presented.     

Surface Adsorption and Aggregation Properties of Novel l-Lysine-Based Gemini Surfactants

Four chiral l-lysine-based gemini surfactants with different spacers were synthesized, namely, disodium (18R,23R)-12,20,21,29-tetraoxo-13,19,22,28-tetraazatetracontane-18,23-dicarboxylate([C₁₂-2-C₁₂]Na₂), disodium (18R,25R)-12,20,23,31-tetraoxo-13,19,24,30-tetraazadotetracontane-18,25-dicarboxylate([C₁₂-4-C₁₂]Na₂), disodium(18R,27R)-12,20,25,33-tetraoxo-13,19,26,32-tetraazatetratetracontane-18,27-dicarboxylate([C₁₂-6-C₁₂]Na₂), disodium(2R,2′R)- 2,2′-(6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl)bis(6-dodecanamidohexanoate) ([C₁₂-T-C₁₂]Na₂). The chemical structures of the prepared compounds were confirmed by ¹H-NMR, ESI–MS and IR spectra. Further, the critical micelle concentration (CMC) of these surfactants in aqueous solutions was determined by surface tension and conductometry methods at 25 °C. Moreover, the adsorption and micellization behaviors of these surfactants were estimated by pC₂₀, the minimum average area per surfactant molecule (A_min), and standard free energy for micellization and adsorption ( \( \Updelta G_{\text{mic}}^{^\circ } \) and \( \Updelta G_{\text{ads}}^{^\circ } \) ). The results show that the four gemini surfactants have low CMC values and significantly low surface tension. Furthermore, the surfactants show strong adsorption at the air–water interface. The CMC and A_min values of the surfactants were found to be in the order of [C₁₂-2-C₁₂]Na₂ < [C₁₂-4-C₁₂]Na₂ < [C₁₂-6-C₁₂]Na₂ < [C₁₂-T-C₁₂]Na₂, which were in agreement with the sequence of \( \Updelta G_{\text{mic}}^{^\circ } \) and \( \Updelta G_{\text{ads}}^{^\circ } \) . The circular dichroism of the surfactants indicated the formation of chiral aggregates above the CMC values.     

Synthesis and single-crystal structures of fully dehydrated fully Sr2+-exchanged zeolite Y (FAU) and its benzene sorption complex, |Sr37.5|[Si117Al75O384]-FAU and |Sr37.5(C6H6)33(H2O)15|[Si117Al75O384]-FAU

Single crystals of zeolite Y, |Na₇₅|[Si₁₁₇Al₇₅O₃₈₄]-FAU, were Sr²⁺ ion exchanged and fully dehydrated to generate |Sr_37.5|[Si₁₁₇Al₇₅O₃₈₄]-FAU (crystal 1) and next, benzene adsorbed to generate |Sr_37.5(C₆H₆)₃₃(H₂O)₁₅|[Si₁₁₇Al₇₅O₃₈₄]-FAU (crystal 2, partially dehydrated). Crystal 1 was prepared by ion exchange in a flowing stream of aqueous 0.05 M Sr(ClO₄)₂ for 3 days followed by dehydration at 673 K and 1 × 10^?6 Torr for 2 days. To prepare the benzene sorption complex (crystal 2), another dehydrated |Sr_37.5|[Si₁₁₇Al₇₅O₃₈₄]-FAU crystal was exposed to 50 Torr of benzene for 3 days at 294 K followed by evacuation for 30 min. at this temperature and 5 × 10^?5 Torr. Their structures were determined crystallographically at 100(1) K using synchrotron X-radiation in the cubic space group Fd $ \bar{3} $ m. They were refined to the final error indices R ₁/wR ₂ = 0.051/0.125 and 0.057/0.154 using 598 and 590 reflections with F _o > 4??(F _o) for crystals 1 and 2, respectively. In crystal 1, about 37.5 Sr²⁺ ions per unit cell are found at an unusually large number of crystallographically distinct positions, six. Eight Sr²⁺ ions per unit cell are at the centers of the double 6-rings (D6Rs, site I). Five additional Sr²⁺ ions are near site I. The site-I?? positions (in the sodalite cavities opposite D6Rs) are occupied by 2.5 Sr²⁺ ions per unit cell. Two Sr²⁺ ions are located at site II?? in the sodalite cavity. The remaining twenty Sr²⁺ ions are found at two nonequivalent sites II (in the supercages) with occupancies of 9 and 11 ions per unit cell, respectively. Each of these Sr²⁺ ions coordinates to three framework oxygens. In this crystal, all sites are only sparsely occupied. In crystal 2, all Sr²⁺ ions are located at four crystallographic sites and 33 benzene molecules are found at two distinct sites within the supercages. One Sr²⁺ ion is at the center of the D6R. Fifteen Sr²⁺ ions are located at site I??. The remaining 21.5 Sr²⁺ ions are found at two nonequivalent sites II with occupancies of 19 and 2.5 ions per unit cell. Nineteen benzenes lie on threefold axes in the supercages, where they interact facially with the latter 19 site-II Sr²⁺ ions; occupancy = 19 molecules/32 sites. The remaining fourteen benzene molecules are found in 12-ring planes; occupancy = 14 molecules/16 sites. Each hydrogen of these 14 benzenes is ca. 2.9 Å from six 12-ring oxygens.     

Supramolecular π–π assembly of a neutral [Cu(salen)] complex via the templating effect of an ionic inorganic complex Na2[Cu(mnt)2] forming a framework type material having well-defined channels

A classical ionic inorganic complex Na₂[Cu(mnt)₂] (mnt²⁻ = maleonitriledithiolate = 1,2-dicyanoethylenedithiolate), that acts as a template in assembling neutral [Cu(salen)] (salen = bis(salicylidene)ethylenediamine) complexes forming a framework type arrangement, is accommodated in the channel formed in the crystal structure of a new type of host–guest compound [Cu(salen)]₄ · Na₂[Cu(mnt)₂] (1). The non-covalent supramolecular interactions among [Cu(salen)] complexes and between [Cu(salen)] and [Cu(mnt)₂]²⁻ complexes in the crystal lattice of 1 result in weak antiferromagnetic coupling.     

Preparation and structural study of fully dehydrated,highly Mg2+-exchanged zeolite Y (FAU,Si/Al = 1.56) from undried methanol solution

Single-crystal of fully dehydrated, Mg²⁺-exchanged zeolite Y, |Mg_34.5Na₆|[Si₁₁₇Al₇₅O₃₈₄]-FAU (Si/Al = 1.56), was successfully prepared from undried methanol solution (water concentration 0.02 M). A crystal of Na-Y was treated with 0.05 M MgCl₂ ·6H₂O in the solvent at 333 K, followed by vacuum dehydration at 723 K and 1 × 10^?6 Torr for 2 days. Its structure was determined by single-crystal synchrotron X-ray diffraction techniques, in the cubic space group \(Fd\overline{3} m\) at 100 K. It was refined to the final error indices R ₁/wR ₂ = 0.0587/0.2210 with 1,294 reflections for which F _o > 4σ(F _o). In the structure of |Mg_34.5Na₆|[Si₁₁₇Al₇₅O₃₈₄]-FAU, 34.5 Mg²⁺ ions per unit cell are found at four different crystallographic sites: 15 per unit cell are located at site I at the center of the hexagonal prism [Mg–O = 2.216(2) Å], two are at site I’ in the sodalite cavity near the hexagonal prism [Mg–O = 2.20(3) Å], only one is located at site II’ in the sodalite cavity [Mg–O = 2.197(23) Å], and the remaining 16.5 are at site II near single 6-oxygen rings in the supercage [Mg–O = 2.103(3) Å]. The residual 6 Na⁺ ions per unit cell are found at site II [Na–O = 2.218(7) Å]. No water molecules are found in this structure.     

Influence of MeF2 (Me = Mg, Ca, Sr, and Ba) on the electrical properties of glasses in the MeF2-Na2B4O7 system

Glasses in the MeF₂-Na₂B₄O₇ (Me = Mg, Ca, Sr, and Ba) system have been synthesized. It is shown that the glass formation is observed at a MeF₂ content of up to 40 mol %. The influence of the MeF₂ content on the electrical conductivity and the fluorine concentration in the glass bulk is examined. From the analysis of the concentration dependence of the electrical conductivity with due regard for the fluorine content, it is concluded that the glass structure is predominantly built up of the polar groupings Na⁺[BO_4/2]^-, Na⁺[F-BO_3/2], Me _1/2 ²⁺ [BO_4/2]⁻, Me _1/2 ²⁺ [F⁻BO_3/2], [MeF_4/2], and [MeF_6/3] and the BO_3/2 nonpolar structural-chemical units. The electricity transport is governed by the migration of sodium ions formed upon dissociation of the Na+[BO_4/2]^-and Na+[F^-BO_3/2] groupings. An increase in the MeF₂ content leads to a decrease in the total concentration of sodium ions, a decrease in the Na⁺[BO_4/2]^- concentration, and an increase in the Na⁺[F^-BO_3/2] concentration. Upon introduction of MeF₂ up to ∼20 mol %, the fluorine losses during the synthesis are caused by the dehydration of glass melt. An addition of 20–25 mol % MeF₂ brings about the saturation of the glass by the [F^-BO_3/2]-type structural units, so that the fluorine concentration reaches a saturation in the structures of calcium-, strontium-, and barium-containing glasses and increases in magnesium-containing glasses, owing to the formation of the [MgF+_6/3] groupings.     

Influence of MeF2 (Me = Mg, Ca, Sr, and Ba) on the electrical properties of glasses in the MeF2-Na2B4O7 system

Glasses in the MeF₂-Na₂B₄O₇ (Me = Mg, Ca, Sr, and Ba) system have been synthesized. It is shown that the glass formation is observed at a MeF₂ content of up to 40 mol %. The influence of the MeF₂ content on the electrical conductivity and the fluorine concentration in the glass bulk is examined. From the analysis of the concentration dependence of the electrical conductivity with due regard for the fluorine content, it is concluded that the glass structure is predominantly built up of the polar groupings Na⁺[BO_4/2]^-, Na⁺[F-BO_3/2], Me _1/2 ²⁺ [BO_4/2]⁻, Me _1/2 ²⁺ [F⁻BO_3/2], [MeF_4/2], and [MeF_6/3] and the BO_3/2 nonpolar structural-chemical units. The electricity transport is governed by the migration of sodium ions formed upon dissociation of the Na+[BO_4/2]^-and Na+[F^-BO_3/2] groupings. An increase in the MeF₂ content leads to a decrease in the total concentration of sodium ions, a decrease in the Na⁺[BO_4/2]^- concentration, and an increase in the Na⁺[F^-BO_3/2] concentration. Upon introduction of MeF₂ up to ∼20 mol %, the fluorine losses during the synthesis are caused by the dehydration of glass melt. An addition of 20–25 mol % MeF₂ brings about the saturation of the glass by the [F^-BO_3/2]-type structural units, so that the fluorine concentration reaches a saturation in the structures of calcium-, strontium-, and barium-containing glasses and increases in magnesium-containing glasses, owing to the formation of the [MgF+_6/3] groupings.     

Influence of ionic speciation on electrocatalytic performance of polyaniline coated platinum electrode: Fe(III)/Fe(II) redox reaction

Porous-polyaniline coated Pt electrode (PANI/Pt) was electro-synthesized potentiodynamically in 0.1 M aniline + 0.5 M H₂SO₄ and morphologically characterized by scanning electron microscopy (SEM). Nature of predominant Fe-species in HCl and H₂SO₄ was checked by UV-vis spectrophotometry. Electrocatalysis of Fe(III)/Fe(II) reaction was studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) for three different solution compositions viz. (i) FeCl₃/FeCl₂ in 1 M HCl, (ii) FeCl₃/FeCl₂ in 0.5 M H₂SO₄ and (iii) Fe₂(SO₄)₃/FeSO₄ in 0.5 M H₂SO₄. For different thicknesses of PANI, the peak current increased irrespective of the nature of the Fe-species, but the polarity of the charge on the Fe-species showed great influence on reversibility of electrocatalysis by PANI/Pt. The Donnan interaction of the polyaniline modified electrode for the three compositions was investigated with respect to [Fe(CN)₆]³⁻/H₂[Fe(CN)₆]²⁻ which are believed to be the predominant species present in K₃[Fe(CN)₆]/K₄[Fe(CN)₆] solution in 0.5 M H₂SO₄. The electrocatalytic performance of PANI/Pt for Fe(III)/Fe(II) redox reaction was found superior in HCl compared to that in H₂SO₄.     

A new type of supramolecular assembly consisting of crown ether complex cation and a polyoxometalate anion: Synthesis and crystal structure of [Na(C20H24O6)(CH3CN)2]2[Mo6O19] · 4CH3CN

A novel supramolecular assembly consisting of sodium-dibenzo-18-crown-6(DB18C6) complex cation [Na(C₂₀H₂₄O₆)(CH₃CN)₂]²⁺ and isopolyanion [Mo₆O₁₉]²⁻ has been demonstrated in the 3D structure of [Na(C₂₀H₂₄O₆)(CH₃CN)₂]₂[Mo₆O₁₉] · 4CH₃CN (1). Weak intermolecular forces (C–HO hydrogen bonds) between isopolyanion and crown ether play a significant role in the construction of supramolecular framework in the crystal structure of 1. Compound 1 has been characterized in the solid state by single crystal X-ray diffraction, IR, CHN analysis, and TGA.     

Synthesis, Characterization and Thermogravimetric Analysis of Two Dicyclohexyl-18-crown-6 Pd, Pt Isomaleonitriledithiolate Complexes

Two organic–inorganic hybrid dicyclohexyl-18-crown-6 complexes, [K(DC18C6-B)]₂[Pd(i-mnt)₂] (1) and [K(DC18C6-A)]₂[Pt(i-mnt)₂] (2) (DC18C6-A=cis-syn-cis-dicyclohexyl-18-crown-6, A isomer; DC18C6-B = cis-anti-cis-dicyclohexyl-18-crown-6, B isomer; i-mnt=1,1-dicyanoethene-2,2-dithiolate, isomaleonitriledithiolate), were synthesized by the reaction of dicyclohexyl-18-crown-6 with K₂(i-mnt) and PdCl₂ or K₂PtCl₄ respectively. These were characterized by elemental analysis, FT–IR, UV–Vis spectroscopy and single crystal X-ray diffraction. In complex 1, two [K(DC18C6-B)]⁺ complex cations and one [Pd(i-mnt)₂]²⁻ complex anion formed a neutral molecule through two K–N coordination bonds. The resulting molecule adopted a 1D chain arrangement via K N weak interactions. Complex 2 showed a 1D chain-like structure that was assembled by two [K(DC18C6-A)]⁺ complex cations and one [Pt(i-mnt)₂]²⁻ complex anion through N–K–N interactions. An erratum to this article can be found at     

Voltammetric investigation of thallium adsorption on silver single crystal electrodes

The adsorption behaviour of Tl⁺ on Ag(100) and Ag(111) in 0.5 M NaClO₄ and Na₂SO₄ has been studied by voltammetric methods including flow-through thin layer voltammetry (FTTL) and single electrode thin layer voltammetry (STL). The Tl-deposits formed on both electrode substrates exhibit the ideal charge stoichiometry of metal monolayer adsorbates, indicating the absence of anion adsorption. The adsorption on Ag(100) can be characterized by an equilibrium Γ(E)-isotherm compatible with a stepwise formation of three stable sorption layers. The Tl-deposit on Ag(111) features the successive build up of two adsorbate layers. In case of incomplete formation of the first layer, however, a slow structural transformation occurs, involving a strong interaction with the Ag(111) substrate and accompanied by partial Tl-desorption. The complex behaviour of this system is interpreted in terms of internal strain within the Tl-superlattice structures.     

Electrical Properties and the Structure of Glasses in the xNa2O–(1 – x)2PbO · B2O3 System

The temperature–concentration dependences of the electrical conductivity and the activation energy for electrical conduction of glasses in the Na₂O–B₂O₃ and Na₂O–2PbO · B₂O₃ systems are studied. The investigation into the nature of the electrical conduction in these glasses reveals that the contribution from the electronic component (10^–3%) of the conductivity is within the sensitivity of the Liang–Wagner technique. A considerable alkali conductivity is observed upon introduction of more than 12 mol % Na₂O. The true transport number of sodium _Na is as large as unity at [Na₂O] 15 mol %. It is shown that the observed temperature–concentration dependences of the electrical and transport properties are governed by the ratio between the concentrations of polar and nonpolar structural–chemical units of the Na⁺[BO_4/2]^–, Na⁺[O^–BO_2/2] Na⁺[O^–BO_2/2], Pb²⁺ _1/2[BO_4/2]^–, Pb²⁺ _1/2[O^–BO_2/2], and [BO_3/2] types.     

A novel polyoxometalate chain constructed from sandwich lanthanide-containing polyanion [Ce(PW11O39)2] and sodium ion linker

A novel sandwich-type lanthanide polyoxometalate (NH₄)₂[N(CH₃)₄]₆Na₂[Ce(PW₁₁O₃₉)₂] · 14H₂O (1) has been synthesized and characterized by cyclic voltammetry, IR spectroscopy and single crystal X-ray diffraction. X-ray diffraction result reveals that the sandwich-type polyanions are linked by sodium ions to form a structure of zigzag chains, and the chains are further connected into an extensive two-dimensional (2D) framework depending on hydrogen bond.     

A novel Dawson-like cerium(IV)-hybridizing selenotungstate Na13H7[Ce(SeW17O59)2]·31H2O

A novel cerium(IV)-hybridizing selenotungstate with Dawson-like structure Na₁₃H₇[Ce(SeW₁₇O₅₉)₂]·31H₂O (1) has been synthesized by reaction of Na₂WO₄·2H₂O, Na₂SeO₃ and (NH₄)₂Ce(NO₃)₆ in the aqueous solution and characterized by elemental analysis, IR spectrum, UV spectrum, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. To the best of our knowledge, 1 stands for 1:2-type Dawson-like selenotungstate constructed from two identical [SeW₁₇O₅₉]^12 − moieties combined via one Ce^4 + ion. The Ce^4 + cation displays a distorted square prismatic geometry defined by eight oxygen atoms from two [SeW₁₇O₅₉]^12 − moieties. In the [Ce(SeW₁₇O₅₉)₂]^20 − polyoxoanion, the {SeO₃} trigonal pyramid encapsulated into the [SeW₁₇O₅₉]^12 − fragment is situated on the side close to the Ce^4 + ion. The TGA curve of 1 reveals two steps of weight loss between 25 °C and 700 °C. Furthermore, the electrochemical and the electrocatalytic properties of 1 have been measured by cyclic voltammetry (CV) in 0.5 M Na₂SO₄ + H₂SO₄ aqueous solution.     

A new 3D supramolecular compound containing 1D chains and 1D water chains

The first crystal structure involving the discrete unsubstituted 1,2,4-triazolate anion is reported. In the title compound, [Na₂(H₂O)₈]_n(trz)_2n [trz = 1,2,4-triazolate] (1), each sodium(I) ion is coordinated by six water molecules with a slight distorted octahedron geometry. Each Na(I) are bridged by two μ₂-aqua ligands and arranged in an alternating fashion to construct a 1D zigzag {[Na₂(H₂O)₈]²⁺}_n chain. The 3D supermolecular framework is formed with 1D {[Na₂(H₂O)₈]²⁺}_n chain as the assembly units, by 1D water chain and 1,2,4-triazolate anion as the hydrogen bonding spacers.     

Structural effects on the interactions of benzene and naphthalene sulfonates with activated carbon cloth during adsorption from aqueous solutions

Interactions of benzene and naphthalene sulfonates with activated carbon cloth (ACC) during adsorption from aqueous solutions were investigated. Systematically chosen sulfonates were sodium salt of benzene sulfonic acid (NaBS), disodium salt of 1,3-benzene disulfonic acid (Na₂BDS), sodium salt of 1-naphthalene sulfonic acid (NaNS), disodium salt of 1,5-naphthalene disulfonic acid (Na₂NDS) and trisodium salt of 1,3,(6 or 7)-naphthalene trisulfonic acid (Na₃NTS). The adsorption behaviors of these adsorbates from solutions in water and in 0.01 M H₂SO₄ onto the ACC were monitored by in-situ UV–visible spectroscopic technique. The order of rates and extents of adsorption of sulfonates were explained in terms of acidity of the medium and structural factors influencing the interactions between sulfonates and the ACC surface. Kinetic data of adsorption were treated according to pseudo first-order, pseudo second-order, Elovich and intra-particle diffusion models. The best model representing the experimental kinetic data was found to be the pseudo second-order model. Adsorption isotherms of the sulfonates onto the ACC were derived at 30 °C. Isotherm data were found to fit the Freundlich model better than the Langmuir model.