Pharmaceutical compounds photolysis: pH influence.

The operating parameters of photolytic and photocatalytic reaction processes directly affect the efficiency in the degradation of compounds. In particular, pH is a variable that needs to be considered as it exerts great influence on adsorption, absorption, solubility, among others. This study describes the application of the photolytic process, at different pHs, in the degradation of different pharmaceutical compounds.

Assessment comparison of commercial TiO and TiO sol-gel on the degradation of caffeine using artificial radiation.

The presence of endocrine disrupting compounds in water receptor bodies, such as drugs, currently has in scientific field a great focus of studies focused on advanced water treatment techniques that enable the decontamination of water sources and public supply. In this context, this study focused on the characterization and evaluation of photocatalytic activity of catalysts calcined and uncalcined synthesized TiO and the commercial sol-gel route from caffeine degradation. The photocatalysts were characterized by N physisorption, X-ray diffraction, scanning electron microscopy (SEM/EDS), photoacoustic spectroscopy, and infrared spectroscopy (FTIR).

Adsorption of herbicide 2,4-D from aqueous solution using organo-modified bentonite clay.

This study analyzed the performance of organophilic clays obtained from the chemical modification of sodium bentonite clay when applied to the adsorption of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). Kinetic curves and equilibrium isotherms were obtained in order to determine time and adsorption capacity of the material, as well as understand the mechanisms involved in this phenomenon. The results showed that the most predictive kinetic model for experimental data was of pseudo-second order (R > 0.

Adsorption of Diuron from aqueous solution onto commercial organophilic clay: kinetic, equilibrium and thermodynamic study.

Due to their abundance in nature, clays have been frequently studied in the adsorption of different emergent contaminants, since they have good efficiency and low cost. Therefore, the present study aimed to evaluate the performance of commercial organoclays as an adsorbent in the environmental remediation of wastewater containing the herbicide Diuron. The clay was characterized by the techniques of N physisorption, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and point of zero charge.

Immobilization and characterisation of a lipase from a new source, Bacillus sp. ITP-001.

A new source of lipase from Bacillus sp. ITP-001 was immobilized by physical adsorption on the polymer poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHBV) in aqueous solution. The support and immobilized lipase were characterised, compared to the lyophilised lipase, with regard to the specific surface area, adsorption-desorption isotherms, pore volume (V(p)) and size (dp) by nitrogen adsorption, differential scanning calorimetry, thermogravimetric analysis, chemical composition analysis, Fourier transform infrared spectroscopy and biochemical properties.

Protic ionic liquid as additive on lipase immobilization using silica sol-gel.

Ionic liquids (ILs) have evolved as a new type of non-aqueous solvents for biocatalysis, mainly due to their unique and tunable physical properties. A number of recent review papers have described a variety of enzymatic reactions conducted in IL solutions, on the other hand, to improve the enzyme's activity and stability in ILs; major methods being explored include the enzyme immobilization (on solid support, sol-gel, etc.), protic ionic liquids used as an additive process.