The anaerobic decomposition in landfills produces a gas mixture known as landfill biogas. This biogas consists mainly of CH4 and CO2. The CO2 removal can be carried out by means of adsorption. In order to promote CO2 removal, zeolite type 4A was used as solid adsorbent. The synthesized zeolite was characterized by scanning electron microscopy and X-ray diffraction. CH4/CO2 mixture isotherms were obtained in a magnetic suspension balance equipped with a gas dosing unit and Extended Langmuir and Extended Sips models were used to predict mixture isotherms from monocomponent data. Three biogas emissions drains in a sanitary landfill in Caucaia (Ceará State, Brazil) - ASMOC - were chosen to test the performance of zeolite as CO2 adsorbent under real conditions. Zeolite 4A has proven to be very selective for CO2 even in the presence of H2S.

Perfumes are products mainly consisting of ethyl alcohol, water and fragrance. These fragrances are responsible for characterizing the pleasant and unique odor of each perfume. Among the fragrances, we highlight a group of fragrances which can cause contact allergy, leading to dermatitis. Brazilian and the European law state that when these concentrations of allergenic fragrances exceed the limit of 0.01% for non-rinse products and 0.001% for products with rinsing, the manufacturer is obliged to discriminate on its label their presence. This work aims to quantify allergic fragrances in original and Brazilian perfume using solid-phase microextraction and analyze by gas chromatography-mass detector.