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Pelletization of ca. 50 wt % amine/silica carbon dioxide sorbents was achieved with the novel combination of fly ash (FA) as a strength additive and hydrophobic poly(chloroprene) (PC) as a binder. The PC content and overall synthesis procedure of these materials were optimized to produce pellets, labeled as FA/E100‐S_(20/80)_12.2, with the highest ball‐mill attrition resistance (<0.5 wt % by fines, 24 h) and maximum CO2 capture capacity of 1.78 mmol CO2 g−1. The strength of the pellets was attributed to hydrogen‐bonding of the relatively homogeneous PC network with the interlocked FA and BIAS particles (DRIFTS, SEM‐EDS). The low degradation of 3–4 % in the pellet's CO2 capture capacity under both dry TGA (7.5 h) and practical fixed‐bed (6.5 h dry; 4.5 h humid,≈5 vol % H2O) CO2 adsorption–desorption conditions highlights the pellet's excellent cyclic stability. These robust pellet characteristics make PC/FA/sorbent materials promising for commercial scale, point‐source CO2 capture.

The use of different types of zeolites (X, Na-P1, and 4A) synthesized by different methods and scales were tested in this work to adsorb nutrients present in synthetic solutions and industrial effluents for later application as fertilizer. Modifications with calcium chloride were performed on the zeolite with the best performance to increase its adsorption capacity. The best performing zeolite was type X (ZXH) produced on a pilot scale by the hydrothermal process. Its adsorption capacity without modification was 149 mg P-PO 4 /g zeolite and 349 mg K/g zeolite. With the change, there was a fourfold increase in these results, which were up to threefold higher than reported in the literature. The kinetic model that best characterized the adsorption process was the intraparticle diffusion model, and the equilibrium isotherm was that of Freundlich. The adsorption tests performed with industrial effluent showed high removal of the nutrients of interest (> 90% for PO 4 3− and > 95% for K + ). The desorption tests with zeolites nutrient-loaded from synthetic solutions showed 13 to 24% PO 4 3− and 14 to 47% K + release within 24 h, while for zeolite nutrient-loaded from effluent the release were 7 and 100% for PO 4 3− and K + , respectively. The results we obtained in this work indicated the potential use of zeolites in the treatment of effluent and its application as a fertilizer.

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