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A direct and practical method for photocatalyzed hydrodecarboxylation of fatty acids is reported herein. The catalytic system consists of a commercially available acridinium salt as the photocatalyst and thiophenol as the Hydrogen Atom Transfer (HAT) co-catalyst. Results evidenced that C n -1 alkanes were obtained in yields up to 77%. Furthermore, the protocol was employed for a complex mixture of fatty acids bio-derived from a real sample of licuri oil to obtain hydrocarbons in the range of C 9 -C 17 with high selectivity and excellent conversion (>90%). This work provides a powerful strategy for producing drop-in biofuels under mild conditions. Finally, an energetic assessment of our proposed protocol (∼22.9 kW h) reveals the benefit of a sustainable production of renewable hydrocarbons., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this work, the electrochemical oxidation of the Methyl Red (MR) dye and the herbicide sodium 2,4-dichlorophenoxyacetate (2,4-DNa) was investigated on Si/BDD, Pb/PbO 2 and Ti/Sb-doped SnO 2 anodes in aqueous acidic medium by applying 30 mA cm -2 at 298 K. The electrochemical experiments were carried out in a two-compartment electrochemical cell separated through a Nafion® membrane (417 type) in order to use two types of supporting electrolyte to measure the elimination of the organic compound, the hydrogen production and the amount of oxygen produced during the oxidation of the pollutants. Although the main goal of this study is to understand the relationship between both processes, the evaluation of the current efficiencies ( η ) is a key parameter to determine the anodic oxidative capacity to degrade the proposed pollutants. The results clearly showed that MR and 2,4-DNa can be oxidized on Si/BDD, Pb/PbO 2 and Ti/Sb-doped SnO 2 anodes; however, significant variations in the oxidation level and η are achieved. Thus, although the MR solutions were completely discolored in all cases, only on the Si/BDD anode was MR oxidized to carboxylic acids in less than 15 min of electrolysis time. On Pb/PbO 2 and Ti/Sb-doped SnO 2 electrodes, the discoloration was slower and the oxidation was quasi-completed, leaving in solution some organic by-products, such as 2-aminobenzoic acid and/or N , N '-dimethyl- p -phenylenediamine, in the fixed electrolysis time. The behavior observed during the elimination of 2,4-DNa is due to its difficulty in degrading the chlorine groups in its aromatic ring which makes 2,4-DNa a more stable molecule. In the first oxidation stage, 2,4-dichlorophenol (2,4-DP) is produced in all cases, but on Si/BDD, this intermediate is quickly consumed. From the polarization curves and Tafel analysis, a reaction scheme for the formation and consumption of 2,4-DP was proposed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this work, results concerning hydrogen gas production during the oxidation of methyl red (MR) and sodium 2,4-dichlorophenoxyacetate (2,4-DNa), is presented, emphasizing not only the amount of hydrogen gas that was produced but also the kinetic and efficiency parameters involved in this process. For this purpose, a two-compartment electrochemical cell was used with a Nafion® membrane as separator in order to collect H 2 without other chemical species (only with traces of water vapor). Under these experimental conditions, it was possible to guarantee the purity of the H 2 collected. The electrochemical oxidation of MR and 2,4-DNa solutions was carried out by applying 30 mA cm -2 at 298 K, using different non-active anodes (Si/BDD, Pb/PbO 2 , or Sb-doped SnO 2 ) and different cathodes (Pt mesh, 316-type stainless-steel, or Pt-10%Rh) in order to investigate the effect of the electrocatalytic materials and experimental conditions. Thus, the H 2 produced was measured as a function of the electrolysis time and compared with the values estimated by Faraday's law. The results showed that the hydrogen production rate r (H 2 ) is independent of the nature of the anodic material, although an important effect on the oxygen production was observed on the BDD anode by using sulfuric acid as supporting electrolyte. The effect was discussed through the formation of sulphate-oxidizing species (SO 4 - ˙ and S 2 O 8 2- ) which interfere in the oxygen production step on BDD anodes. The use of different cathodes showed small changes in the hydrogen production rate r (H 2 ), which were basically associated with the differences in hydrogen adsorption energy prior to its evolution. The results were discussed in light of the existing literature., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)