In this work Ni(II) and Cr(III) adsorption on Durvillaea antarctica surface were studied, optimal condition of pH, adsorption time is achieved at pH 5.0, with contact times of 240 and 420 minutes for a maximum adsorption capacity of 32.85 and 102.72 mg g–1 for Ni(II) and Cr(III), respectively. The changes in the vibration intensity of the functional groups detected in the starting material by Fourier transform infrared spectroscopy and the opening of the cavities after the biosorption process detected by scanning electron microscopy images suggested the interaction of the metal ions with the surface and the changes in the chemical behavior of the solid. The heavy metal adsorption equilibrium data fitted well to the Sips model. The effect of competitive ions on adsorption equilibrium was also evaluated, and the results showed that the two metals compete for the same active sites of the biosorbent; the increase of the Ni(II) initial concentration increases its adsorption capacity but decreases the adsorption capacity of Cr(III).

In the present work, the synthesis of aerogels was carried out from a mixture of resorcinol–formaldehyde as the precursors. The synthesis conditions used were those adjusted to obtain micropore materials. These solids were obtained through two synthesis routes: acid and base catalysis. The obtained materials were activated with CO2 and water vapor. It was determined that the carbonization of the aerogels obtained by the basic medium (ACB 1050) develops a greater percentage of microporosity, which decreases after the activation processes. The adsorption capacity of CO2 and CH4 at 50 bar on the surface of this material is 12.6 and 6.0 mmol g–1, respectively.

In this work, aerogels were prepared using resorcinol-formaldehyde as a precursor in two synthetic routes, one basic and one acidic, to perform the adsorption of CO 2 at 0 • C and atmospheric pressure. Aerogels were Characterization by N 2 and CO 2 Physisorption, Raman Spectroscopy, Scanning Electron Microscopy, and Infrared Spectroscopy. In general, was found that aerogels have a polymeric, disordered, three-dimensional structure and have a microporous surface. Langmuir, Freundlich, Sips and Toth equilibrium models present a good data fit of CO 2 adsorption at relative pressure ranging between 1 × 10 −4 and 3 × 10 −2 . The diffusion intra-particle kinetic model explains the setps of this process; the Elovich model also showed a good fit, therefore, there are an energetic heterogeneity of the CO 2 superficial adsorption sites. The aerogel carbonized in basic medium at 1050 • C (ACB 1050) material was the best adsorbent of this pollutant, reaching an adsorption capacity of 6.43 mmol g −1 .Achieving economic and favorable separation of CO 2 from gas mixtures represents one of the main technological and environmental problems facing our society today [10]. The most studied post-combustion technology is chemical adsorption. Monoethanol amine (MEA) has been the chemical most used for this purpose. Alternative solvents, such as piperazine and ammonia, have also been proposed to achieve this objective [6]. The advantage of this method is the low partial pressure that is used because the CO 2 molecules are easily absorbed over liquids in flue gas streams [11]. The disadvantage is that the use of amine alkoxysilanes is very expensive [12], and the method requires high regeneration energy due to the large emission of combustion gases and the costs of repairing the process equipment [4]. Other common methods to achieve CO 2 sequestration include separation in membranes, cryogenic and biological methods, and physical adsorption [13].Capture and storage technology has been considered the best option to reduce carbon dioxide emissions from large sources, and particularly adsorption is considered a promising process to separate gas mixtures [14]. This process is inexpensive, requires less regeneration energy, is easy to handle, has fast kinetics, and has a high capacity of CO 2 adsorption and selectivity [4]. The adsorbents provide a high surface area, which is a fundamental parameter in this process. Among the different adsorbents, 13X zeolite has been investigated to adsorb CO 2 by oscillating the pressure [6]. It is generally recognized that CO 2 is physically adsorbed to activated carbon, mainly by condensation or liquefaction in pores with widths that are less than 1 nm [15]. The adsorption of this greenhouse gas in nanopore materials has also been investigated in zeolites exchanged with alkali metals, amino-modified and modified alkaline, mesoporous silicas, microporous polymers, carbons, and metalorganic structures [10]. It has also been established that the chemical properties of activated carbon play a relevant role in...

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Aerogels are extremely porous materials with large pore volumes and low bulk densities. Their unique structure imparts extraordinary properties and wide applications. The synthesis of pyrogallol-formaldehyde xerogels has been reported using HClO 4 as a catalyst, but according to the literature review the synthesis of aerogels of these materials has not been documented. In the present work, the data for the synthesis of aerogels pyrogallol-formaldehyde are presented using oxalic acid and hydrochloric acid as catalysts. Also includes the data of the characterization of these materials by Infrared spectroscopy, thermogravimetric analysis Tg-DTG, Physisorption of N 2 , Raman Spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It was determined that the use of these precursors of the synthesis of aerogels in acid medium, leads to the obtaining of microporous solids with a high value of the surface area, the material with the highest value of this parameter has been CAePF OA550 at have a BET area value of 1066 m 2 g −1 .