Sustainable Ecocements: Chemical and Morphological Analysis of Granite Sawdust Waste as Pozzolan Material

The processes focused on stone cutting generate a large volume of waste. Small size waste, silt/clay, is not used and goes to landfill. However, the composition of these wastes makes them useful for adding to cements and for use in construction. In the present paper, 10% Ordinary Portland cement is replaced by 10% waste from granite sawmill, which is studied to obtain sustainable ecological cement. This replacement provides advantages from the morphological and chemical point of view at the cements. The waste has a particle size that does not exceed 15 µm and that when replacing in the cement, after the hydration reaction, generates structures where Calcium Silicate Hydrate (C-S-H) gels and double layered hydroxide compounds (LDH) are reaction products formed in high concentration. These products develop stable phases in the structures over long time periods such one year, which was the time frame used in this study.

Photodegradation of Rhodamine B using Cd-Al/C double layered hydroxide catalyst

This paper presents the degradation of Rhodamine B using cadmium aluminium carbon (Cd-Al/C) catalyst under visible light. The layered double hydroxide was successfully prepared from cadmium fluoride (CdF2), aluminium chloride (AlCl3), and rice husks activated carbon, and then characterized by X-ray Diffaraction (XRD) Scaning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) methods. The peaks at 2Ө 23.4 and 35.5 in the XRD result confirmed the presences of LDH. The effect of contact time, catalyst dosage, pH and initial concentration, on the photo degradiation of Rhodamine B were investigated. The experimental results showed that after 100min visible light irradiation, the percentage degradation using 200mg Cd-Al/C, pH 7 and 3ppm Rhodamine B concentration reached to 76.22%. For kinetics studies the data obtained were analysed using pseudo first order and pseudo second order kinetic models. From the linear regression coefficient values the data were found to be best fitted to pseudo second order kinetics. The results revealed that the Cd-Al/C show good catalytic activity. Key words: Layered Double Hydroxide (LDH) Cadnium fluoride, Aluminium Chloride and Rhodamine B.

Ciprofloxacin Based on Carrier Double Layered Hydroxide Nano-particles of Fe+3/Fe+2, Fe+3/Ni+2, Al+3/Fe+2, and Al+3/Ni+2 Ions

The double-layered hydroxide nano-particles compounds with ciprofloxacin drug were carried out by preparation of the double layered hydroxide (DLH) of M+3/M+2 ions for selective ions. The ciprofloxacin drug was inserted between them. The resulted compounds were characterized by X-Ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and Fourier Transform Infrared (FT-IR) spectroscopy; the antibacterial studied done by using the gram (+) and gram (-) pigments.

Liraglutide Drug Loading with Double Layered Hydroxide- Synthesis and Characterization

The liraglutide, antidiabetic drug, was loaded with layered double hydroxide nanoparticles for selective ions such as Fe+3, Fe+2, Ni+2 and Al+3, the LDH were prepared through the titration method by adding 2M of NaOH to the mixture of trivalent, divalent ions and 0.5M HCl, the drug liraglutide was added to Prepared layered. The compounds were characterized by SEM, AFM, FT-IR, XRD and Zeta potential technique.

Comparative Adsorptive Removal of Phosphate and Nitrate from Wastewater Using Biochar-MgAl LDH Nanocomposites: Coexisting Anions Effect and Mechanistic Studies

In this study, date-palm biochar MgAl-augmented double-layered hydroxide (biochar–MgAl–LDH) nanocomposite was synthesized, characterized, and used for enhancing the removal of phosphate and nitrate pollutants from wastewater. The biochar–MgAl–LDH had higher selectivity and adsorption affinity towards phosphate compared to nitrate. The adsorption kinetics of both anions were better explained by the pseudo-first-order model with a faster removal rate to attain equilibrium in a shorter time, especially at lower initial phosphate-nitrate concentration. The maximum monolayer adsorption capacities of phosphate and nitrate by the non-linear Langmuir model were 177.97 mg/g and 28.06 mg/g, respectively. The coexistence of anions (Cl−, SO42−, NO3−, CO32− and HCO3−) negligibly affected the removal of phosphate due to its stronger bond on the nano-composites, while the presence of Cl− and PO43− reduced the nitrate removal attributed to the ions’ participation in the active adsorption sites on the surface of biochar–MgAl–LDH. The excellent adsorptive performance is the main synergetic influence of the MgAl–LDH incorporation into the biochar. The regeneration tests confirmed that the biochar–MgAl composite can be restored effortlessly and has the prospective to be reused after several subsequent adsorption-desorption cycles. The biochar-LDH further demonstrated capabilities for higher removal of phosphate and nitrate from real wastewater.

Hydrotalcite and Hydrocalumite in Mortar Binders from the Medieval Castle of Portilla (Álava, North Spain): Accurate Mineralogical Control to Achieve More Reliable Chronological Ages

Mortars from different stratigraphic units at Portilla Castle (Alava, North Spain) have been analyzed for mineralogical characterization before radiocarbon dating. The mortar binder at Portilla Castle is composed not only of neoformation calcite but also of double-layered hydroxide (LDH) minerals such as hydrotalcite and hydrocalumite. The mineralogy of several fractions of the binder has been analyzed to determine the granulometric distribution of minerals in the binder. The continuous monitoring of mineralogy during the extraction of different grain size fractions has been performed by using a scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analyses (TGA). Hydrotalcite and hydrocalumite-bearing mortar binders give older ages than expected since they introduce dead carbon into the system.