Profile of inorganic elements of seaweed from the Brazilian Northeast coast.

The contents of 24 elements were determined in seven species of macroalgae collected in Ceara-Brazil, in the rainy and dry seasons of 2022. The samples were digested, and the analytes were quantified by ICP-OES and Hg by direct analyzer. The CRM CD-200 was analyzed for accuracy and obtained recoveries were higher than 95 %. The seaweed species have different inorganic element profiles with predominant elements being: Ca, K, Na, Mg and P. The Sargassum vulgare species stood out for its Hg and As contents (1.479 ± 0.005 mg kg-1 and 172 ± 6 mg kg-1, both in the rainy seasons). Ulva lactuca attracted attention for its high concentration of V (46.4 ± 3.4 mg kg-1, rainy season). In general, the elemental content levels in the macroalgae samples were higher in the rainy season. Long-term studies to comprehend the effect of seasonality on the elemental composition of seaweed must be carried out.

Chemometric characterization of alembic and industrial sugar cane spirits from cape verde and ceará, Brazil.

Sugar cane spirits are some of the most popular alcoholic beverages consumed in Cape Verde. The sugar cane spirit industry in Cape Verde is based mainly on archaic practices that operate without supervision and without efficient control of the production process. The objective of this work was to evaluate samples of industrial and alembic sugar cane spirits from Cape Verde and Ceará, Brazil using principal component analysis. Thirty-two samples of spirits were analyzed, twenty from regions of the islands of Cape Verde and twelve from Ceará, Brazil. Of the samples obtained from Ceará, Brazil seven are alembic and five are industrial spirits. The components analyzed in these studies included the following: volatile organic compounds (n-propanol, isobutanol, isoamylic, higher alcohols, alcoholic grade, acetaldehyde, acetic acid, acetate); copper; and sulfates.

Adsorption of polycyclic aromatic hydrocarbons from aqueous solutions by modified periodic mesoporous organosilica.

A novel procedure was developed for the synthesis of a periodic mesoporous organosilica (PMO), which was used to remove polycyclic aromatic hydrocarbons (PAHs) from aqueous solutions. Adsorption equilibrium isotherms and adsorption kinetics experiments were carried out in solutions of PAHs (2-60 mg L(-1)), using the PMO as adsorbent. Adsorption models were used to predict the mechanisms involved. The adsorption kinetics data best fitted the pseudo-first-order kinetic model for naphthalene, and to the pseudo-second-order model for fluorene, fluoranthene, pyrene, and acenaphtene. The intraparticle model was also tested and pointed to the occurrence of such processes in all cases. The isotherm models which best represented the data obtained were the Freundlich model for fluoranthene, pyrene, and fluorene, the Temkin model for naphthalene, and the Redlich-Peterson model for acenaphtene. PAHs showed similar behavior regarding kinetics after 24 h of contact between adsorbent and PAHs. FTIR, XRD, BET, and SEM techniques were used for the characterization of the adsorbent material.