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Mordenite zeolite is considered a molecular sieve because of its adsorbent material characteristics used in the industry as a gas separator. High Si/Al ratios of this zeolitic material in its crystal lattice provide high thermal stability in the structure. To minimize the production costs, this work synthesized the mordenite zeolite in absence organic template (high costs of production). For this purpose, rice husk ash (silicon source) was used from a thermoelectric plant that uses biomass for power generation under the “Moving Grade Reactor” method and metakaolin (aluminium source) derived from the construction. To obtain the zeolitic material, an alkaline treatment with sodium hydroxide and deionized water was required. Different Si/Al ratios (5, 10, 15, and 20) were used to evaluate the highest efficiency in adsorption capacity. The textural properties of mordenite as a function of specific surface area ranged from 314 to 347 m 2 /g, with micropore volume 0.198–0.279 cm 3 /g with average pore diameter ranging from 5.9 to 6.2 Å. N 2 adsorption/desorption isotherms obtained for mordenite presented type IV hysteresis, characteristic of microporous materials. X-ray diffraction showed crystalline phases of mordenite zeolite, mostly. The FTIR reinforces the success of mordenite synthesis by the vibration bands corresponding to the zeolitic material. TGA revealed water desorption and absence of an organic director. The mean cation-exchange capacity values ranged from 1.10 to 1.78 meq/g indicating a 62% increase of 20-mordenite zeolite compared to 5-mordenite in the zeolitization process. This result is satisfactory and promising for the use of mordenite as adsorbent material.

The textile industries release a substantial amount of effluents into water resources every year. The vast majority of these effluents are composed of heavy metals that bind the textile fibres with dyes. This work proposes to use an adsorption system composed of clay-minerals (kaolinite and montmorillonite) and molecular sieve (zeolite) for separating the Cu 2+ and Cr 6+ ions, considering the pH changes of aqueous solutions. The adsorbent materials were characterized using the following state of the art techniques such as X-ray fluorescence, X-ray diffraction, Raman spectroscopy and Cation exchange capacity. During the adsorption tests, the contact time of the adsorbates (Cu 2+ and Cr 6+ ions in concentrations of 100, 50, 10 and 5 mg/L) with the adsorbents vary from 1 to 4 h in acidic and alkaline conditions (pH 3.5 and 7.5). The results indicate maximum adsorption of Cu 2+ (at pH 3.5) and Cr 6+ (at pH 7.5) ions on application of the zeolitic material. The clay minerals conclusively proved to be less efficient when compared to zeolite. It can be concluded that the adsorption system has achieved the desired efficiency, with substantial removal of Cu 2+ and Cr 6+ ions for zeolites in synthetic wastewater solutions of the textile industry.

Rice husk is considered as a waste in the rice industry but is proficient in manufacturing different materials, such as zeolites, which is produced in large quantities all over the world, for example in Brazil. Zeolite is an adsorbent support material, which can be synthesized from rice husk ash (RHA) with external sources of aluminium (ESA). The scientific community has been conducting several measures to minimize the environmental impacts caused by greenhouse gases. Several mitigation processes are presently investigated, which includes carbon dioxide injections into adsorbent materials (e.g. zeolites). The efficiency of this technology involves a zeolitic material with high crystallinity and high concentrations of SiO2 and Al2O3 (aluminosilicates). In the present work, zeolites have been synthesized from rice husk ash (SiO2 source) and external aluminium sources (Al2O3 - alumina, gibbsite and metakaolin) to fulfill that purpose. With the aid of XRF, XRD, SEM/EDS and FTIR techniques, the zeolitic material was characterized in two distinct crystalline phases: Mordenite and ZSM-5. The synthesis was carried out by the ideal addition of ESA (2.5 g) to RHA. According to the literature, the zeolitic materials formed by the mixture of Mordenite and ZSM-5 can be availed for gas separation and greenhouse gas storage.

Diagenetic alteration in the Eocene turbidite reservoirs of Espírito Santo Basin has been envisaged through geochemical modeling using TOUGHREACT software. Extensive albitization has been encountered, accompanied by the dissolution of detrital plagioclase and K‐feldspars. The diapiric impregnation of the succession by halokinesis and the resulting high salinity of pore water suggest that diagenesis was invigorated by the entry of brine from the salt diapirs. The circulation of high‐temperature fluids from the diapirs through fractures is the main cause of the late diagenetic reactions, thereby influencing the reservoir quality. This behavior is accompanied by concomitantly growing authigenic quartz crystals as derived from the fluid‐inclusion study. Based on the available geological and geochemical data, a series of computer simulations present the effects of fluid percolating through the reservoir and non‐reservoir depositional elements deposited from sediment‐gravity flows, along with the influence of this interaction with the salt domes. The simulations were carried out in batch mode to stabilize the water with sandstone and the results were then utilized in a series of 1D simulations. A nominal water flow of 10 cm y −1 was assumed in isothermal conditions at 100 °C. In this scenario, the precipitation of calcite in sandstone was considered to occur due to the presence of thermobaric flow. Its authigenic precipitation is strongly controlled by the dissolution of plagioclase. The simulations carried out with TOUGHREACT reveal the potential of the simulator to model the complex diagenetic cases of turbiditic reservoirs in an analog stratigraphic configuration. The simulations also demonstrate the need to dynamically integrate the diagenesis associated with the sandstones so that the obtained results can be consistent with the real diagenetic patterns.