Sewage sludge from the galvanic industry represents a problem to the environment, due to its high metal content that makes it a hazardous waste and must be treated or disposed of properly. This study aimed to evaluate the sludge from three galvanic industries and determine its possible use as catalysts for the synthesis of materials. Catalyst was obtained from a thermal process based on dried between 100–120 °C and calcination of sludges between 400 to 700 °C. The physical–chemical properties of the catalyst were analyzed by several techniques as physisorption of N2 and chemisorption of CO of the material. Catalytic activity was analyzed by thermogravimetric analysis of a thermo-catalytic decomposition of crude oil. The best conditions for catalyst synthesis were calcination between 400 and 500 °C, the temperature of reduction between 750 and 850 °C for 15 min. The catalytic material had mainly Fe as active phase and the specific surface between 17.68–96.15 m2·g−1, the catalysts promote around 6% more weight-loss of crude oil in the thermal decomposition compared with assays without the catalyst. The results show that the residual sludge of galvanic industries after thermal treatment can be used as catalytic materials due to the easiness of synthesis procedures required, the low E-factor obtained and the recycling of industrial waste promoted.

Thermal decomposition of cocoa pod husks under inert and oxidizing atmospheres was studied. Samples from Cotopaxi, Ecuador were used as raw material. Thermogravimetry based experiments were used to obtain decomposition data vs. temperature. A novel strategy to fit the TG and DTG curves was used giving good fit by considering, in the kinetic model, four biomass fractions following independent reactions. Analytical pyrolysis was used to determine the composition of volatile compounds obtained in slow (150–350, 350–500 °C) and flash pyrolysis (400 °C). The results indicate that in the slow pyrolysis experiments at low temperatures (150–350 °C), the highest area percentages correspond to ketones (7.5%), organic acids (12.5%) and phenolic derivatives (10%), while at increased temperatures (350–500 °C) the higher percentages are clearly focused on phenolic derivatives (12%) and aromatic compounds (10%). Comparing the results of flash pyrolysis at 400 °C (i.e., higher heating rate but lower final temperature), an increase in the yield of ketones and organic acids is observed compared to slow pyrolysis, but the percentage of phenols and aromatics decreases. The results obtained allow deducing the operating conditions to maximize the mass fraction of the different functional groups identified.

Caffeine (1,3, is a natural molecule present in a variety of plants, seeds or fruits, standing out in coffee, tea, mate, cola nuts, cocoa and guarana. It is widely used in different industries, acting as a stimulant for respiratory and central nervous systems. Ilex guayusa L. is located in the Amazon region of Colombia, Ecuador and Peru. Plant leaves present alkaloids such as caffeine and theobromine. In this work, extraction of caffeine from Ilex guayusa L. leaves using supercritical carbon dioxide (SCCO2) was studied. The overall caffeine recovery from plant matrix was determined as a function of time (0.17, 0.5, 1, 2 and 4 h) at the same extraction conditions (23 MPa and 328 K). Ethanol as cosolvent was introduced in the extraction vessel to soak the vegetable material before SCCO2 was

Los materiales tradicionales derivados del petróleo como el polietileno y polipropileno son los más empleados en el campo de la protésica, sin embargo, la tendencia a la protección del medio ambiente amerita el análisis de nuevos materiales biodegradables y biocompatibles. El ácido poliláctico (PLA) es un polímero obtenido a partir de fuentes naturales, que se usa entre muchas aplicaciones en prótesis ortopédicas por su bajo costo. Con el desarrollo de la nanotecnología, pueden incorporarse nanopartículas de diferente naturaleza con el objetivo de mejorar las propiedades mecánicas del PLA, sin embargo, existe información limitada. En este compendio se describen las propiedades físicas y químicas del PLA, así como las condiciones para su impresión en 3D. Se analizan varios nanomateriales tales como nanocelulosa, nanofibras de quitosano, nanotubos de carbono, grafeno, óxido de titanio, nanopartículas de óxido de hierro, nanopartículas de plata, nanopartículas de sílice mesoporosa, entre otras. Se describen estudios referentes sus propiedades químicas, mecánicas y biocompatibilidad. Como resultados se encontró que algunos nanomateriales han sido combinados con PLA, los estudios realizados para comparar sus propiedades mecánicas, muestran mejores resultados usando nanopartículas. Muy pocos estudios in vivo se han realizado, únicamente nanotubos de carbono, grafeno, óxido de titanio, nanopartículas de plata y nanopartículas de sílice mesoporosa. Se concluye que el uso de nanomateriales puede mejorar potencialmente las propiedades mecánicas del PLA, sin embargo, se requieren los estudios experimentales correspondientes, además que se deben usar modelos animales para evaluar su efecto a nivel tisular y determinar si son aptos para la combinación o recubrimiento de prótesis.