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Glass-ceramic material prepared with sugar cane bagasse ash as one of the raw materials was characterized to determine some important properties for its application as a coating material.X-ray diffraction patterns showed that wollastonite-2M (CaSiO 3 ) was the major glass-ceramic phase. The Rietveld method was used to quantify the crystalline (60 wt.%) and vitreous (40 wt.%) phases in the glass-ceramic. The microstructure (determined by scanning electron microscopy) of this material had a marble appearance, showing a microporous network of elongated crystals with some areas with dendritic, feather-like ordering. Microhardness data gave a mean hardness value of 564.4 HV (Vickers-hardness), and light microscopy disclosed a greenish brown colored material with a vitreous luster.

carbons (ACs) with well-developed microstructure and high microporosity were obtained from biomass by potassium hydroxide activation. The preparation process consisted in producing carbon materials in the ratios of activating agent to raw material 70:30, 50:50, 30:70 and 25:75 (w/w) characterized by thermal analysis coupled to spectroscopy (TG-DTA / FT-IR), scanning electron microscopy (SEM), N 2 adsorption isotherms at -196 °C and activation isotherm at 500 and 600 °C for 3.0 h. Specific surface areas (SBET) within 728 and 1712 m 2 g -1 and (S mic ) within 1054 and 1923 m 2 g -1 were obtained, while the micropores surface area was calculated using the Dubinin-Astakhov (DA) equation and the pore size distribution calculated from density functional theory (DFT) was found to be in the range 1.09 -1.77 nm. Adsorption isotherms were fitted using Langmuir and Freundlich non-linear models and the adsorption capacity determined for methylene blue dye was between 27.13 and 459.20 mg g -1 .

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This work proposes for the first time the use of biochar (BC) as a cost‐effective electrode modifier for simultaneous electroanalysis of similar organic compounds. BCs were prepared from Babassu petiole pyrolysis at five temperatures (500–900 °C) and characterized by FTIR, SEM, TG‐DTA and BET., which presented amorphous shapes with relative high surface areas (280–396 m2 g−1) and polar surface groups (T<700 °C). As a proof of concept, BC‐modified glassy carbon electrodes (BC/GCE) were studied using ferrocyanide probe and evaluated towards the simultaneous detection of catechol and hydroquinone (isomers), levofloxacin and norfloxacin (analogous structure), and tert‐butylhydroquinone and butylated hydroxyanisole. In all cases, BC improved the peak‐to‐peak separation, sensitivity and electrocatalytic activity, which highlights BC as a promising modifier to be used in simultaneous determinations of organic compounds with similar peak potentials.