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-Chromium is a pollutant present in tannery wastewater, its removal is necessary for protection of the environment. Penisetum purpureum, Brancharia decumbens and Phragmites australis were grown hydroponically in experimental gravel beds to determine their potential for the phytoremediation of solutions containing 10 and 20 mg Cr dm . These concentrations, similar to tannery wastewater after initial physicochemical treatment were used with the aim of developing an economic secondary treatment to protect the environment. All the systems achieved removal efficiencies of 97 -99.6% within 24 hours. P. purpureum and B. decumbens removed 78.1% and 68.5% respectively within the first hour. Both P. purpureum and B. decumbens were tolerant of the concentrations of chromium applied, but P. purpureum showed the greatest potential because its faster growth and larger biomass achieved a much greater chromium removal over the whole length of time of the experiment.

Optimization of hydrocortisone-loaded nanoemulsion formulation was achieved by low energy emulsification method. D-optimal mixture design was used with the variables parameters of Tween-20, lipoid S75, palm kernel oil ester (PKOE) and deionized water towards a response (viscosity). Hydrocortisone, ethanol and phenonip were kept constant (1.0, 24 and 0.5 wt. %). The mixing rate and time were kept constant at 400 rpm and 4 h, respectively. The optimum formulation conditions were successfully predicted. From the results obtained, it shows that the higher the concentration of palm kernel oil ester, the less the viscosity of the nanoemulsion. The optimized formulation showed good stability with the viscosity of 2.85 Pa.s. The particle size, polydispersity index and zeta potential of the optimized nanoemulsion gave a result of 172.56 nm, 0.184 and-50.03 mV, respectively. The results are in agreement with the TEM micrograph. The viscosity of the optimized nanoemulsion decreased with increased shear rate, showing a shear thinning behaviour (pseudoplastic) suitable for pharmaceutical application.

Wet granulation of microcrystalline cellulose (MCC) has the objective of minimizing particle losses caused by elutriation in compression and coating processes. The MCC physical properties suggest the conventional fluidized bed as adequate for the granulation process; however, literature reports the occurrence of poor fluidization dynamic (preferential channels and dead zones) during this particle fluidization. This work reports the granulation of MCC in vibrofluidized bed, using aqueous solution of maltodextrin (35%) as binder. A fractional experimental design (2 5 − 1 ) was developed to assess the influence of process variables: amplitude and frequency of vibration, atomization pressure, inlet air temperature, and granulating solution flow rate on the responses: particle growth, angle of repose, lump index and mass of elutriated particles. The results showed an increase of the Sauter mean diameter related to the original value from 3.17 to 33.11%, confirming the granulation of the material. The granules obtained revealed good flowability and low lumps index. The levels of independent variables that resulted in a higher reduction of elutriation were the same ones that provided the highest growth of the particles.