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Four organic solid wastes (coffee grounds, ground nut shell, paper money sewage sludge and cork powder) have been investigated as bloating inducing agents in lightweight aggregate (LWA) manufacturing when mixed in small proportions (2.5 wt.%) with three types of clays. The pellets obtained were fired in a rotary kiln at the maximum feasible temperature for 4 min. A similar impact was observed both in the working conditions and in the properties of the LWAs, showing that the differences between said residues are not as decisive as those of the clays to which they are added. The organic wastes have played a crucial role in achieving reducing conditions inside the aggregate. Thus, their addition has led to substantial improvements both from an operational point of view, lowering the working temperature, and from a technological perspective, favoring bloating and the development of a highly porous and lightweight structure. Leachate studies have shown that the LWAs meet the regulatory limits. The outcomes of this investigation show that, in line with the precepts of the Circular Economy, the recovery of organic wastes of different nature can have a place in the production of environmentally friendly LWAs

This work describes a study on the incorporation of waterborne fluoropolymer dispersions into paint formulations to act as a film forming binder for matting purposes. The waterborne fluoropolymer dispersions were prepared employing miniemulsion polymerization, reaching concentrations of 80–100 wt% of the fluorinated polymer in the backbone. Afterwards, different pigmented paints were prepared using the waterborne fluoropolymers as self-matting co-binders. Different strategies were used to incorporate the waterborne fluoropolymers into the paint formulation, which also included the partial substitution of commercial matting agents. The pigmented paints were applied onto different substrates and the matting efficiency evaluated. The results clearly showed that these waterborne fluoropolymers can be used as an alternative replacement for commercial matting agents, while adding value to the coating by offering enhanced hydrophobicity as compared to regular acrylic binders.

The preparation of superhydrophobic coatings with good mechanical properties from waterborne dispersions is reported. This goal is achieved combining a high solids fractal dispersion of a hard and hydrophobic polymer and a film forming polymer dispersion (not necessarily hydrophobic) in a dual-casting strategy. The coatings are superhydrophobic (water contact angle > 150°) and oleophobic (olive oil contact angle = 120°). The mechanical strength was demonstrated by means of scrub resistance tests. The approach meets the requirements of the industrial coatings as it uses environmentally friendly waterborne polymer dispersions that can be produced in high tonnage and can be easily applied to large and irregular surfaces forming cohesive, non-porous and mechanically resistant coatings. In addition, no special preparation of the substrate is needed.

Aqueous secondary and tertiary alkanolamine mixtures are novel absorbents for carbon dioxide removal. This study evaluates the CO 2 absorption by aqueous mixtures of diisopropanolamine (DIPA) and triethanolamine (TEA) in a bubble column reactor considering the influence of the mixture composition, gas flow rate and time on the hydrodynamic parameters, reaction mechanism and mass transfer coefficient. The nuclear magnetic resonance spectroscopy (NMR) was performed to evaluate the possible synergic effects produced by the use of this alkanolamine mixture. The gas flow rates were 18, 30 y 40 L h −1 and the total concentration of the mixtures was 10% of total weight, varying the proportions of DIPA and TEA. The composition of the mixtures (corresponding to the 10% of amine)was varied over the entire composition range.

The carbon dioxide absorption process by 1-amino-2-propanol (MIPA) and bis(2-hydroxypropyl)amine (DIPA) aqueous solutions in bubble column reactor have been studied considering the influence of liquid phase physical properties and the amine group substitution on the overall process. The main objective of this work was to establish the carbon dioxide capture reaction mechanism for these systems, and then to obtain the predominant stoichiometry to calculate the mass transfer coefficient. NMR technique was used to determine the species present in the liquid phase during the absorption process and to confirm the reaction mechanism. The degradation of these amines was also evaluated.

Experimental data of density, viscosity, speed of sound, surface tension and refractive index for binary mixtures of N-methyl-2-pyrrolidone with diethanolamine (or triethanolamine) were measured over the entire composition range and for temperatures included between (293.15 and 323.15) K. The effects of mixture composition and temperature, upon these physical properties previously commented, were studied. Different models have been used to fit experimental values of these properties. Derived properties such as excess molar volume, isentropic compressibility and isentropic compressibility excess were calculated. Also, excess molar volumes dependence on composition was fitted using a Redlich–Kister type equation.

We assessed the influence of alcohol-free beer on factors implicated in atherosclerosis, such as lipid profile, oxidative stress parameters, and proinflammatory cytokines, in postmenopausal women, a population particularly at risk for atherosclerotic disease.The study was carried out in 29 nuns, 58 to 73 y old, who live in a convent with a disciplined, regular, and homogeneous lifestyle. The nuns maintained their habits and diet routine, but their meals were supplemented with 500 mL/d of alcohol-free beer (0.0%) divided into two doses over a 45-d period. Lipid profile, inflammatory markers such as C-reactive protein, interleukins 1 and 6, and tumor necrosis factor-alpha, and parameters of oxidative metabolism were determined before and after the study period.There were no differences in the levels of C-reactive protein and proinflammatory cytokines after diet supplementation. The antibody titers to oxidized low-density lipoprotein were significant lower (P0.05), and thiobarbituric acid-reactive substances (-18%, P0.001) and plasma carbonyl group content (-21%, P0.001) were decreased when compared with initial values. Increases in alpha-tocopherol levels (+9%, P0.05) and erythrocytic glutathione levels (+29%, P0.001) were also noted. With respect to lipid profile, only subjects with cholesterol levels higher than 240 mg/dL showed lower levels after supplementation.Consumption of non-alcoholic beer produces a decrease in oxidative stress that can have a beneficial impact on cardiovascular risk; however, the circulating concentrations of inflammatory mediators involved in its pathophysiology remained unchanged.