Carbon Chain Length Of Alcohols Research Articles

Investigating C3 and C4 esters and alcohols in a diesel engine: Combined influence of carbon chain length, oxyfuel type, and oxygen content

Diesel engines fueled by liquid fuels will continue to dominate the transportation and heavy machinery application market despite the advancement of other technologies. Studies have yet to be conducted to investigate the combined influence of carbon chain length, oxyfuel type, oxygen content, and blending ratio of esters and alcohols as additives in diesel fuel. The present study addresses this by preparing two sets of experiments using three-carbon (C3) and four-carbon (C4) additives, one at an equal blending ratio of 4% and the other at an equal oxygen mass content of 1.94%. Although the additives caused up to 24.84% rise in brake specific fuel consumption at low load, the value diminished to 7.86% at medium load and 11.63% at high load. The C4 fuels were found to have better NOx reduction potential than the C3 fuels. However, most additives significantly increased CO emissions, except for EE4.9 (4.9% ethyl ethanoate and 95.1% diesel), leading to 3.7% and 7.1% lower CO emissions than neat diesel at low and medium loads, respectively. Smoke emissions were also reduced by up to 32.84% when oxygenated additives were used. Although all blends tested are promising fuel alternatives in a diesel engine, EE4.9 provided the most suitable trade-off between engine performance and emissions.

Impact of carbon chain length of alcohols on the physicochemical properties and reactivity of exhaust soot

Particle is the main pollutant in diesel engine exhaust, which seriously endangers human health and the atmospheric environment. The use of alcohol fuels in diesel engines can effectively reduce particle emissions, but alcohol fuels with different carbon chain lengths will affect the generation process of particles, which in turn changes the physicochemical properties and oxidation characteristics of the particles. Therefore, it is particularly important to study the properties of particle emitted by diesel engines fueling alcohol fuels with different carbon chain lengths. The physicochemical properties of soot emitted from commercial diesel engines were studied by thermogravimetric analyzer, HRTEM (high-resolution transmission electron microscopy), and XPS (X-ray photoelectron spectroscopy) in this paper, respectively. The diesel engine used alcohol-diesel blends of different carbon chain lengths with the same oxygen content as fuels, such as methanol/diesel blend (M10), n-butanol/diesel blend (NB25), and n-octanol/diesel blend (NO45), and pure diesel fuel was used as a reference. The results showed that the use of alcohols reduced the fractal dimension (Df) of particles, and the NB25 particles had the smallest Df. Moreover, the particles of blended fuels had smaller primary particle diameter (dp) compared to pure diesel. However, with the use of short-chain to long-chain alcohols, an increasing tendency of dp was observed. In terms of the nanostructure, as the use of short-chain to long-chain alcohols, the La (fringe length) increased, both the d (fringe separation distance) and Tf (fringe tortuosity) reduced, which was not favorable for the oxidation of the particles. In addition, in terms of oxygenated surface functional groups (SFGs), the CO group occupied a higher proportion in most working conditions relative to the groups of CO and COO. Further analysis showed that the dp and nanostructure had more influence on the oxidation behavior of soot than Df and oxygenated SFGs.

THERAPEUTIC INDICES OF SOME ANTIFUNGAL ORGANIC COMPOUNDS

Objective: The objective of the study was to evaluate the therapeutic indices (TIs) some antifungal organic compounds and to compare their safety.
 Methods: TIs of 55 organic compounds were evaluated by dividing their mammalian toxicity values given as median lethal doses ([mg/kg] rat, oral) collected from literature by experimentally determined fungitoxicity values evaluated as median effective concentration (EC50 [mg/L]) for the mycelial growth inhibition of Colletotrichum gloeosporioides on potato dextrose agar medium.
 Results: Large variations in TIs are observed in different classes of compounds, namely, alcohols, carboxylic acids, phenols, esters, and aldehydes. The relationship between carbon chain length of saturated monohydric alcohols and mammalian toxicity shows that toxicity increases from chain length 1 to 5, declines from 5 to 6, increases from 6 to 7, and steadily declines from 7 to 10. Thus, the relationship is by and large parabolic. The relationship between carbon chain length and molar antifungal activity is also parabolic. In spite of this, large differences are found in TIs making 1-decanol (TI=42.1) a very safe antifungal compound and 1-pentanol (TI=0.17) a hazardous antifungal compound. This is because mammalian toxicity reaches a maximum around carbon chain length of 5, while in the case of antifungal activity, it reaches a maximum around carbon chain length of 10.
 Conclusions: Among the 55 compounds, whose TIs were evaluated, some compounds with high TIs (>10) which can be considered safe as antifungal compounds are citronellol, geraniol, 1-decanol, 1-octanol, phenyl acetaldehyde, methyl anthranilate, 1-naphthol, 2-naphthol, and propionic acid. Some compounds with low TIs (<0.50) which can be considered hazardous as antifungal compounds are resorcinol, hydroquinone, oxalic acid, and acetyl acetone.

Lumichrome tautomerism in alcohol-water mixtures: Effect of carbon chain length and mole fraction of alcohols

Alcohol-water mixtures are important solvent systems, widely used in many applications. In this study, the intriguing water induced tautomerism of the fluorescent chromophore, Lumichrome (LC), has been explored to reveal interesting changes in the solvent environments of alcohol-water mixtures of methanol (MeOH), ethanol (EtOH), n-propanol (PrOH) and tert-butanol (t-BuOH), as a function of the carbon chain length/alkyl group size and concentrations of the alcohols. Since LC remains in the alloxazine form in pure aqueous medium, the appearance of emission from the isoalloxazine tautomer in alcohol-water mixtures provides compelling evidence that addition of alcohol disrupts the H-bonded network structure of bulk water to facilitate the availability of isolated water molecules in the solvent medium, which can form the required LC-water precursor complex for conversion of the alloxazine form to isoalloxazine form. Interestingly, two estimated parameters for LC tautomerism, namely, Rlong, which is the relative emission contribution of the isoalloxazine form in the fluorescence decay traces of LC (and hence a measure of the population of isoalloxazine form in the solution), and τlag, which is the lagtime involved in the evolution of the isoalloxazine emission band in the time-resolved area normalized emission spectra of LC (and hence a measure of the ease with which the LC-water precursor complex is formed), show a non-monotonic dependence on the mole fraction of alcohols (χalcohol) in the mixed solvent systems. The unique variation of Rlong and τlag with χalcohol, indicates the occurrence of three composition zones in the alcohol-water mixtures, which we correlate with characteristic transformations in the microscopic structures of the solvent mixtures. Our results reveal that the ability of the alcohols to disrupt the H-bonded network structure of bulk water increases with increasing size of their hydrophobic alkyl groups, following the trend, t-BuOH > PrOH > EtOH > MeOH.

Binary solvent systems for durable self-adhesive conductive hydrogels

Abstract Conductive hydrogels without adhesiveness and durability characteristics face great challenges in practical applications, such as inconvenient use, unstable contact voltage, and difficult to store. Herein, we present sodium polyacrylate (PAANa) hydrogels with binary solvent systems composed of water and an alcohol [ethylene glycol (EG), glycerol (GLY), or poly(ethylene glycol) (PEG)] as solvent instead of traditional water to research their self-adhesiveness, durability, conductivity, and mechanical properties. PAANa hydrogels exhibited higher self-adhesive properties and durability after alcohol content increased, and GLY/water hydrogels showed the best self-adhesive and stable properties. With more alcohols added, the weaker conductivity became, and EG/water hydrogels showed the highest conductivity. It was observed the long carbon chain length of alcohol could help improve the rheological properties of hydrogels. Thus, PEG/water hydrogels had the highest storage modulus, loss modulus, and consistency. The results demonstrated that the GLY/water binary solvent could provide good self-adhesiveness and durability, but EG/water and PEG/water showed better conductivity and mechanical properties, respectively. Therefore, our work may provide novel physical insights into the long-term usage of self-adhesive conductive hydrogels to practical requirements.

Calorimetric determination of the thermodynamics of alcohol-surfactant mixed micelle formation: Temperature and concentration effects

The thermodynamic parameters of surfactant/alcohol mixed micelles were determined in mixtures of sodium dodecyl sulfate (SDS) and dodecyltrimethylammonium bromide (DTAB) in a series of solvents composed of varying concentrations of n-propanol (C3OH), n-butanol (C4OH), and n-pentanol (C5OH). Conductivity studies were used to determine CMC values and the degrees of counterion binding. Isoperibol solution calorimetry was used to directly determine CMC values and enthalpy of micellization (ΔmicH). From these experimentally determined values, the Gibbs energy and entropy of micellization were calculated as a function of temperature and alcohol concentration. In general, CMC values decreased with increasing alcohol carbon chain length and concentration but increased with temperature. The effects of temperature, alcohol carbon chain length, and alcohol concentration on the energetics of these mixed micellar systems are explained in terms of the relative contributions to ΔmicH by alkyl chain interactions, hydrophobic effects, and electrostatic contributions.

Numerical study of particle dynamics in laminar diffusion flames of gasoline blended with different alcohols

Alcohols have been considered as promising clean alternative fuels for IC engines. At present, the difference and mechanism of particle dynamics for different alcohols is unclear. In this work, numerical simulation of laminar diffusion flame of gasoline blended with different alcohols was carried out by coupling a gas-phase chemical kinetic model and fixed sectional particle model, then the micro-processes of particle nucleation, growth and oxidation were analyzed. The results show that the dilution effect of different alcohol blending on the reduction of soot is quantitatively similar under the same blending ratio, while the chemical effect increases with the increase of alcohol carbon chain length. The molecular structure of alcohols increases the chemical action during the formation of soot particles. At the same blending ratio, the difference of temperature field caused by adding different alcohols has little effect on the growth of particles. The proportion of PAHs condensation in surface growth increases with the increase of carbon chain length of alcohols. PAHs condensation rate together with HACA rate determines the inhibiting ability of different alcohols on soot particle growth, but PAHs condensation plays a dominant role. With the addition of alcohols, the oxidation rate of O2 decreases, but the oxidation rate of OH increases. However, as the particles formed in laminar diffusion flames of alcohol/gasoline is mainly oxidized by O2, the increase of OH oxidation rate has little effect on particle reduction. From the oxidation region, the particles are oxidized first by OH, then by the co-oxidation of O2 and OH.

Thermophysical study of binary mixtures of 1-butyl-3-methylimidazolium nitrate ionic liquid + alcohols at different temperatures

New experimental data of density and viscosity for the binary mixtures of 1-butyl-3-methylimidazolium nitrate ([Bmim][NO3]) with + 2-propanol, 2-butanol and 2-pentanol are reported over the entire range of mole fraction at T = (293.15–323.15) K. To elucidate possible intermolecular interactions between the chemical species present in solutions, the excess molar volume, VmE thermal expansion coefficient, α excess thermal expansion coefficient, αE the isothermal coefficient of excess molar enthalpy, ∂HmE/∂PT,x partial molar volume, Vi¯ and deviation in viscosity, Δη were calculated. The excess molar volume of the binary mixture is negative over the entire mole fraction range and becomes more negative with increase in the temperature. Deviation in the viscosity is negative over the whole range of composition and decreases with increasing temperature. The obtained excess molar volume and deviation in viscosity were fitted to the Redlich–Kister polynomial equation. The experimental results have been discussed regarding molecular interactions and the formation of complex between unlike molecules. Influences of temperature and carbon chain length of alcohols were discussed.

Combustion and regulated/unregulated emissions of a direct injection spark ignition engine fueled with C3-C5 alcohol/gasoline surrogate blends

Abstract C3-C5 alcohols have gradually drawn more attentions as gasoline alternative fuels. In this paper, an experimental study based on the toluene reference fuel (TRF) was conducted to investigate the combustion and emissions of C3-C5 alcohol/TRF blends in a gasoline direct injection (GDI) engine. The research octane number (RON) of alcohol/TRF blends were kept at 95. Two sets of comparative experiments were performed at constant volume fraction of alcohols and oxygen contents of the mixtures, respectively. The results of ethanol/TRF and gasoline were served as a reference. It can be found that the maximum brake torque/knock-limited spark timing (MBT/KLST) of ethanol/TRF and n-propanol/TRF blends were advanced by 2∼3oCA at 6 bar and 6∼7oCA at 8 bar, comparing with those of n-butanol/TRF and n-pentanol/TRF mixtures. Under the same blending ratio, n-butanol/TRF exhibited the shortest flame development duration and rapid combustion duration along with highest indicated thermal efficiency. With the increase of carbon chain length, the emissions including CO, THC, alkanes, ethylene and propylene, acetylene and aromatics show a trend to drop first and then increase. N-butanol/TRF and n-pentanol/TRF featured lower aldehyde emissions but higher NOx emissions. For blends with the same oxygen content, n-propanol/TRF had the highest indicated thermal efficiency (ITE). Ethanol/TRF and n-propanol/TRF had lower CO emissions but higher NOx emissions. With the increase of alcohol carbon chain length, the alkene, acetaldehyde and acrolein emissions decreased firstly and then increased. Under present operation conditions, the addition of C3-C5 alcohols in gasoline reduced more PM emissions than ethanol did. From the standpoint of combustion and emissions in this gasoline direct injection engine, n-propanol and n-butanol were more suitable candidates as gasoline alternative fuels.

Excess volumes and partial molar volumes of binary liquid mixtures of furfural or 2–methylfuran with alcohols at 298.15 K

In this work, densities, excess molar volumes, partial molar volumes and excess partial molar volumes for binary liquid mixtures of furfural and 2–methylfuran with 1–propanol or 2–propanol or 2–butanol or 1–pentanol or 2–pentanol or 1–hexanol at 298.15 K and 0.1 MPa over the entire range of composition were determined. Excess molar volumes were correlated with Redlich–Kister equation with average absolute deviations smaller than 0.0164. Excess molar volumes were negative for furfural + 1–propanol or 2–propanol and positive for all other studied binary systems. Solute partial molar volumes determined increase as alcohol carbon chain length increase, except for furfural + 2–pentanol, which presented smaller values than 2–butanol for molar fractions below 0.2. A maximum/minimum was observed from the excess partial molar volume plots. FTIR spectra data indicate bands at 3135 cm−1, for furfural systems, and 3122 cm−1 for 2–methylfuran systems, are related to the behavior found for excess molar volumes and that H–bonds are smaller for furfural systems than for 2–methylfuran.

The chain length and isomeric effects of monohydric alcohols on the flotation of magnesite and dolomite by sodium oleate

To improve the flotation efficiency while decreasing costs, mixed reagents composed of sodium oleate (NaOL) and monohydric alcohols were used as collectors for the flotation of magnesite and dolomite respectively. Single mineral flotation followed by measurements of surface tension and FTIR spectra were conducted to investigate the carbon chain length and isomeric effects of alcohols on the flotation and adsorption behavior of NaOL. Compared to NaOL alone, the mixed reagents of NaOL and monohydric alcohols, including butanol, isobutanol, octanol, and isooctanol, improved the recoveries of magnesite and dolomite. Additionally the recoveries increased as the carbon chains of the alcohols lengthened. The recoveries were enhanced in the case of mixed reagents consisting of NaOL and isomeric alcohols compared with those of the reagents composed of NaOL and the corresponding normal alcohols. The coadsorption of NaOL and monohydric alcohols on mineral surfaces could be verified by FTIR spectra. Alcohols could reduce the surface tension of NaOL solutions. Furthermore, the adsorption configurations of the NaOL alone and mixed reagents on the mineral surfaces were further investigated by DFT calculations. The bond population between the O atoms of NaOL and metal atoms of minerals increased with the lengthening carbon chains of the alcohols. When isomeric alcohols were added, the interaction intensities between NaOL and minerals were higher than those with corresponding normal alcohols. Hydrogen bonds formed between NaOL and monohydric alcohols, contributing to the dense hydrophobic layer on mineral surfaces. Additional hydrogen bonding between monohydric alcohols and mineral surfaces could also be observed when alcohols with long carbon chains were added. Finally, the flotation of magnesite and dolomite by NaOL were both enhanced by monohydric alcohols, especially those with long carbon chains and isomeric structures.

Organozinc Precursor-Derived Crystalline ZnO Nanoparticles: Synthesis, Characterization and Their Spectroscopic Properties.

Crystalline ZnO-ROH and ZnO-OR (R = Me, Et, iPr, nBu) nanoparticles (NPs) have been successfully synthesized by the thermal decomposition of in-situ-formed organozinc complexes Zn(OR)2 deriving from the reaction of Zn[N(SiMe3)2]2 with ROH and of the freshly prepared Zn(OR)2 under an identical condition, respectively. With increasing carbon chain length of alkyl alcohol, the thermal decomposition temperature and dispersibility of in-situ-formed intermediate zinc alkoxides in oleylamine markedly influenced the particle sizes of ZnO-ROH and its shape (sphere, plate-like aggregations), while a strong diffraction peak-broadening effect is observed with decreasing particle size. For ZnO-OR NPs, different particle sizes and various morphologies (hollow sphere or cuboid-like rod, solid sphere) are also observed. As a comparison, the calcination of the fresh-prepared Zn(OR)2 generated ZnO-R NPs possessing the particle sizes of 5.4~34.1 nm. All crystalline ZnO nanoparticles are characterized using X-ray diffraction analysis, electron microscopy and solid-state 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The size effect caused by confinement of electrons’ movement and the defect centres caused by unpaired electrons on oxygen vacancies or ionized impurity heteroatoms in the crystal lattices are monitored by UV-visible spectroscopy, electron paramagnetic resonance (EPR) and photoluminescent (PL) spectroscopy, respectively. Based on the types of defects determined by EPR signals and correspondingly defect-induced probably appeared PL peak position compared to actual obtained PL spectra, we find that it is difficult to establish a direct relationship between defect types and PL peak position, revealing the complication of the formation of defect types and photoluminescence properties.

Preparation and characteristics of multiple emulsions containing liquid crystals

ABSTRACTIn this paper, multiple emulsions containing liquid crystals were prepared successfully and the influence of formulation parameters on the formation mechanism was studied. Moreover, differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS) spectra analysis and stability analysis were used to characterise the property of them. The results showed that the chemical structure of water-in-oil (W/O) emulsifiers directly impacted on the formation of multiple structure, but the effect on the formation of liquid crystal structure was negligible. With the gap of the polarity between inner and outer liquid oils decreased, both multiple structure and liquid crystal structure were harder to form. The content of sodium chloride in internal aqueous phase, which should be neither too high nor too low, has great impact on the formulation of multiple structure. It was easier to form two structures simultaneously when the carbon chain length of fatty alcohols was closer to that of emulsifier C22 alkyl polyglucoside (202). DSC elucidated the phase transitions of water in the liquid crystal layer and the W/O emulsions. SAXS indicated that the liquid crystal orientation was lamellar. The stability analysis showed that the presence of liquid crystal structure had a significant contribution to the stability of the multiple emulsions.

Separation of Azeotropes Hexane + Ethanol/1-Propanol by Ionic Liquid Extraction: Liquid–Liquid Phase Equilibrium Measurements and Thermodynamic Modeling

To separate the azeotropes of hexane + ethanol/1-propanol, two ionic liquids [HMIM][BF4] and [HMIM][OTf] were adopted as extractive agents. The corresponding ternary liquid–liquid equilibrium data for the mixtures of hexane + ethanol + [HMIM][BF4], hexane +1-propanol + [HMIM][BF4], and hexane +1-propanol + [HMIM][OTf] were measured at 298.15 K and 101.3 kPa. The distribution coefficient (B) and selectivity (S) were obtained to evaluate the separation performance of the selected extractants to extract ethanol/1-propanol from the azeotropes. Meanwhile, the influence of the ILs’ anions and the alcohol carbon chain length were investigated. In addition, the nonrandom two-liquid (NRTL) and universal quasichemical activity coefficient (UNIQUAC) models were adopted to correlate the ternary liquid–liquid equilibrium data, and the binary interactive parameters were regressed. Also, the calculated results of the models agreeed with the measured data. Meanwhile, the binodal curves of the ternary systems were predict...

Hydration-aggregation pretreatment for drastically improving esterification activity of commercial lipases in non-aqueous media.

We investigated a novel, simple method for activating lipases in non-aqueous reaction media. Lipase powders were suspended in n-fatty alcohols and were then hydrated by adding a small amount of water. A paste-like aggregate was recovered from the mixture followed by lyophilization for obtaining activated lipases as dry powders. Lipase activity was evaluated for esterification between myristic acid and methanol in n-hexane. The activated lipases exhibited high esterification activity depending on the experiment conditions during hydration-aggregation pretreatment such as the amount of added water, the temperature, the pH of added buffer solutions, and the carbon chain length of the n-fatty alcohols used as pretreatment solvents. Various commercial lipases from different origins could be activated by this method. Changes in lipase conformation induced by the hydration-aggregation pretreatment were studied based on fluorescence and Fourier-transform infrared spectroscopy.

Effect of Carbon Chain Length of Alcohols on the Syntheses of Cinnamate Esters by Immobilized Lipase from Bacillus aerius

Background: Celite- immobilized lipase was used to catalyze the esterification reaction between different alcohol of carbon chain in increasing order viz. methanol, ethanol, propanol and butanol to form cinnamate esters in DMSO (solvent) at different temperatures for different time periods in a chemical reactor. Keywords: Bacillus aerius, cinnamate esters, FTIR spectra, lipase immobilization, NMR spectra.

Influence of reaction parameters for the enhanced photocatalytic hydrogen production using surface modified semiconductor Titania nanotubes

The physico-chemical properties of the photocatalyst and nature of reaction solution significantly influences the hydrogen (H2) production efficiency. The reaction parameters like Hydrogen ion concentration (pH) and nature of organic scavengers are aimed to amend the physico-chemical properties of catalyst that functions under natural solar light. CuO (1.5 wt %) loaded titania nanotubes (TNT) was used as a photocatalyst. The lower in the carbon chain length of alcohol (scavenger) and the alkaline reaction conditions are complimentary to each other for the superior rate of H2 production. The enhancement in H2 production is due to the effective interface reactions on the surface of the catalyst are more in number and the most suitable reduction potential of the conduction band of the photocatalyst for the ease of proton reduction. The 1.5 wt% CuO/TNT catalyst was well characterized for structural, morphological and surface elemental composition properties. Further biphasic anatase-rutile structure and one dimensional tubular morphology with +2 state of Cu deposited on the surface of TiO2 are responsible for high rate of gaseous H2 production.

SELECTIVITY OF CANDIDA RUGOSA LIPASE IMMOBILIZED ONTO LAYERED DOUBLE HYDROXIDES AS CATALYST IN SYNTHESIS OF FATTY ACID ESTERS

The enzymatic selectivity of Lipase from Candida rugosa immobilized onto a calcined layered double hydroxide (CLDHs-CRL) towards the chain-length of fatty acids and alcohols in the synthesis of fatty acid esters was investigated. The results showed that CMAN-CRL catalyzed the esterification process with fatty acids of medium chain lengths (C10-C14) effectively while, CNAN-CRL and CZAN-CRL exhibited high percentage conversion in fatty acids with carbon chain lengths of C8-C12 and C10-C18, respectively. In the alcohol selectivity study, CMAN-CRL showed high selectivity toward alcohols with carbon chain lengths of C4, C6 and C10. On the other hand, both CNAN-CRL and CZAN-CRL exhibited rather low selectivity towards longer carbon chain length of alcohols.

Assessment of commercial resins in the biolubricants production from free fatty acids of castor oil

In this work, different commercial resins (Dowex 50W-X8, Amberlyst-15 and Purolite CT275DR) were characterized by FTIR spectroscopy, N2 adsorption-desorption isotherms, elemental analysis (CHNS), SEM, XPS data, TG analysis and acid-base titration to determinate the amount of Brönsted acid sites. These resins were tested in the esterification of free fatty acids coming from the castor oil (FACO) with 2-ethylhexanol for production synthetic biolubricants which display higher biodegradability than the traditional mineral lubricants. Under the operating conditions used, all resins were active in the esterification reaction, obtaining better results for macroreticular resins than gel resin. Amberlyst-15 was the most active catalyst, reaching a conversion value close to 90% after 1h and 100% after 4h of reaction. The effect of different parameters on catalytic performance was studied, optimizing variables such as: temperature, alcohol-fatty acid molar ratio as well as catalyst loading. The influence of increasing alcohol carbon chain length and branching on esterification rate at 80°C was also examined using different alcohols. Likewise, reuse experiments indicate that the Amberlyst-15 resin lost activity after the first cycles but it is almost maintained around 60% from the third cycle. The esters synthesized exhibited better physical properties than those shown for its respective free fatty acid.

Peroxo method for preparation of composite silica–titania spheres

Composite silica–titania spherical particles, from the nanometer to submicron size, have been synthesized via a new template-free method, being achieved by the reaction of aqueous titanium peroxo complex with TEOS (tetraethylorthosilicate) in aliphatic alcohols. The choice of the solvent greatly affects the growth of silica–titania particles. It has been established that size of the spheres increases as carbon chain length of alcohol extends (from methanol to n-propanol). The nanometer size SiO2–TiO2 spheres with mean diameter of about 50nm are formed in the methanol solution, while n-propanol promotes particle growth up to 400nm. The synthesized composites retain amorphous structure up to 500°C due to the formation of Si–O–Ti heterolinkages, whose presence has been confirmed by FTIR and XPS studies.