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NaA zeolite-coated metakaolin granules (MKG@NaA) were successfully synthesized from kaolin mineral by primary growth in the hydrothermal reaction without using glue or a seed crystal. The XRD and SEM analysis results revealed that a layer of NaA zeolite with a typical cubic shape and high crystallinity formed on the surface of kaolin granules. The obtained material was used as an adsorbent for lead metal ion Pb(II) adsorption studies in a fixed-bed column configuration. The operation factors such as the solution inflow rate, Pb(II) concentration, and column height were investigated. The results showed that the adsorption capacity of the material increased with increasing column height and initial concentration of the influent and decreased with increasing flow rate. With the test parameters at the Pb(II) concentration of 100 mg·L-1, the adsorbent bed height of 8.1 cm, and the inflow rate of 2.5 mL·min-1, the lead ion adsorption capacity was 118.5 mg·g-1. The Thomas, Yoon-Nelson, and bed depth service time models were applied to describe the breakthrough curves for Pb(II) ion removal by a fix-bed column using the MKG@NaA absorbent and to predict the column performance under different experimental conditions with good linearity (R2 > 0.95).

Heavy metal and radioactive ions can cause serious environmental problems if they are not completely removed from wastewater as well as in groundwater. In this study, large pore LTL and MOR zeolites were successfully synthesized and used as adsorbent to remove Pb2+, Cu2+, Zn2+, Cd2+, Cs+ and Sr2+ ions in aqueous solution. At low initial concentration (10 ppm), LTL and MOR zeolites effectively removed above metal ions with removal efficiency in the range of 95–99%. Both zeolites showed high affinity to Cs+ and Pb2+ ions with the adsorption capacity of LTL zeolite to Cs+ and Pb2+ were 278.8 mg/g and 141.4 mg/g, and that of MOR zeolite were 238.8 mg/g and 178.9 mg/g, respectively. The EDS results showed that Pb2+ ions from the aqueous solution were exchanged with exchangeable Na+ ions in MOR zeolite and K+ ions in LTL zeolite. The pseudo-second-order kinetic model and Langmuir isotherm model fitted better to experiment data on the adsorption of metal ions on both LTL and MOR zeolite. This result revealed that the adsorption of these metal ions on LTL and MOR zeolite was monolayer chemisorption. The equilibrium adsorption results showed that the microstructure of zeolite significantly affected the adsorption capacity of LTL and MOR zeolite on removal of tested metal ions.

Microporous membrane has shown great potential for the separation of carbon dioxide from the gas mixture. Beside the membrane performance, the membrane preparation method is a factor to be concerned in this technique. In this work, pure silica DDR zeolite membranes on silica porous substrate were synthesized from an economical and environmentally efficient process. Porous silica substrate was fabricated using a low cost material. The membrane growth reaction used a minimum amount of chemical, produced no waste generation. Part of the reactant is supplied from porous substrate. The membrane quality is strongly dependent on the exposed faces of seed crystals and the pH value of the template solution. The obtained membranes show very high permeance and selectivity for CO2 from a CO2/CH4 gas mixture in both dry and humid conditions and hot gas flow. The membrane maintains stability in high performance with the separation factor of 440–500 for a test period of one week.

Amyotrophic lateral sclerosis (ALS) is a multisystemic neurodegenerative disorder. Given that peripheral blood mononuclear cells (PBMCs) serve as a “window to the central nervous system” we aimed to answer whether endoplasmic reticulum (ER) stress in ALS-PBMCs is related to disease aggressiveness. We studied ER stress in the PBMCs of 49 patients with ALS and 31 age- and sex-matched healthy controls. The expression of a main ER stress marker, activating transcription factor 6 (ATF6), was significantly higher in ALS compared to controls, but did not correlate with age, disease severity, disease duration and disease progression rate. When ATF6 expression levels were plotted against relative D50 (rD50)-derived disease phases derived from the D50 ALS model, two distinct clusters of patients were observed: cluster 1, with progressively increasing ATF6 expression levels and cluster 2, which demonstrated stable ATF6 expression over the disease course. Individuals in the two clusters did not significantly differ in terms of ALS Functional Rating Scale-Revised (ALSFRS-R), disease aggressiveness, disease duration and subtype. However, patients with the increasing ATF6 level were significantly younger, indicating that aging processes might be related to ER stress in ALS. Our data suggest that the reaction to ER stress during disease course may be compromised in older patients with ALS.

Joint Research on Environmental Science and Technology for the Earth