Activated carbon derived from sugarcane and modified with natural zeolite for efficient adsorption of methylene blue dye: experimentally and theoretically approaches

The introduction of activated carbon/natural zeolite (AC/NZ) as an efficient and reliable nanoadsorbent for enhancing methylene blue (MB) dye adsorption. By calcining sugarcane waste at various temperatures between 500 and 900 °C, activated carbons (ACs) are formed. Both XRD and SEM were used for the characterization of the prepared adsorbents. Adsorption measurements for the removal of MB dye were made on the impact of pH, beginning MB concentration, and contact time. The maximum AC500/NZ adsorption capacity for MB dye at 25 °C, pH 7, and an AC500/NZ mass of 50 mg was found to be approximately 51 mg/g at an initial concentration of 30 ppm. The pseudo-second-order kinetics model and the Temkin isotherm model describe the adsorption process. The Temkin model shows that the adsorption energy is 1.0 kcal/mol, indicating that the MB-to-AC500/NZ adsorption process occurs physically. Our Monte Carlo (MC) simulation studies supported our findings and showed that the Van der Waals dispersion force was responsible for the MB molecule's physical adsorption. The AC500/NZ adsorbent is thought to be a strong contender for water remediation.

Synthesis and characterization of nanozeolite based composite fertilizer for sustainable release and use efficiency of nutrients

In this research work, we propose macronutrients incorporated slow-release based nano-fertilizer using nanozeolite as a carrier. A simple chemical approach was used to synthesis the proposed nanozeolite composite fertilizer (NZCF). To gain an insight into the properties, morphology and structure of the synthesized NZCF, it was further characterized by different techniques such as powder XRD, FT-IR, SEM, and TG/DTA. A considerable enhancement of the quality and the water retention capacity of the soil was observed as a result of applying the proposed NZCF when compared with a commercial fertilizer. Furthermore, the swelling ratio and the equilibrium water content of NZCF were compared to the commercial fertilizer and their effect on plant growth was observed. Slow-release studies were carried out for both NZCF and the commercial fertilizer. The results of these studies reveled that NZCF possessed a long-term release pattern of the macronutrients and that showed a great potential for promoting plant growth. Hence, the prepared nanocomposite fertilizer can be safely used as an environment-friendly source of nutrients to enhance plant growth.

Zeolite fillers for resin-based composites with remineralizing potential

The objective of the study is to obtain the modified zeolite powders and to apply these materials as active fillers in the dental composites with the remineralizing potential. Three different synthesis pathways were applied to receive LTA-type (Linde A-type) zeolites. All zeolites were subjected to the ion exchange process and mineralization of surface with hydroxyapatite (HA) layer. As a result a calcium form and surface modified form of these materials were prepared. The effectiveness of each modification process was confirmed by X-ray Diffractometry, Infrared and Raman Spectroscopy. Materials were also characterized by Scanning Electron Microscopy, Energy Dispersive Spectroscopy and nitrogen adsorption/desorption measurements. The remineralizing potential was specified as an ability to release calcium ions during the incubation in saline with the use of Inductively Coupled Plasma-Mass Spectrometry. The obtained zeolite fillers were placed in the organic matrix to create photopolymerizable composites with potential dental applications. The homogeneity of the filler distribution in polymeric matrix was checked by the Raman spectra mapping. Composites containing calcium form of zeolites as well as zeolites with the HA layer proved to have the ability to release calcium ions during incubation in saline in the amount comparable to calcium phosphates-filled composites or even higher than dental glass-filled composites. The ability to release calcium ions, together with good mechanical properties and mass stability testify the suitability of prepared composites in potential dental applications.

Effects of a natural sepiolite bearing material and lime on the immobilization and persistence of cadmium in a contaminated acid agricultural soil

Soil contamination with cadmium (Cd) represents a substantial threat to human health and environmental quality. Long-term effectiveness and persistence of remediation are two important criteria for the evaluation of amendment techniques used to remediate soils polluted with potentially toxic metals. In the current study, we investigated the remediation persistence of a natural sepiolite bearing material (NSBM, containing 15% sepiolite) and ground limestone (equivalent to > 98.0% CaO) on soil pH, Cd bioavailability, and Cd accumulation by pak choi (Brassica chinensis L.) during the growth of four consecutive crops in a Cd-contaminated acid soil with different amounts of NSBM (0, 0.2, 0.5, 1, 2, and 5%). Soil pH levels ranged from 5.21 to 7.76 during the first crop, 4.30 to 7.34 during the second, 4.23 to 7.80 during the third, and 4.33 to 6.98 during the fourth, and increased significantly with increasing the application rate of NSBM. Soil CaCl₂-Cd and shoot Cd concentrations decreased by 8.11 to 99.2% and 6.58 to 94.5%, respectively, compared with the control throughout the four cropping seasons. A significant negative correlation was found between soil CaCl₂-Cd and soil pH. Combined use of 0.1% lime and NSBM showed greater effects than NSBM alone, especially, when the application rate of NSBM was ˂ 2%. Moreover, pak choi tissue Cd concentrations in the treatments with NSBM addition alone at ≥ 2% or at ≥ 1% NSBM combined with 0.1% lime met the maximum permissible concentration (MPC) over the four crops, allowed by the Chinese and European regulations. Based on the present study, safe crop production in the test soil is possible at a soil pH > 6.38 and CaCl₂-Cd < 14 μg kg^-1, and soil Cd immobilization by NSBM without or with lime is a potentially feasible method of controlling the transfer of soil Cd into the food chain.

CT-guided aspiration cytology of advanced silicosis and confirmation of the deposited zeolite nano particles through X ray diffraction: A novel approach

Silicosis is a common occupational lung disease, resulting in fibrotic nodular lesions in the upper lobes of the lung parenchyma. Most of the pneumoconioses are diagnosed on the basis of relevant history and clinico-radiological correlation. Image-guided aspiration cytology appears to be poorly yielding and is not usually considered as a diagnostic modality. However, silicosis may sometimes offer a diagnostic challenge because of its radiological resemblance and clinical overlap with pulmonary tuberculosis and neoplastic lesions. We present a unique situation where image-guided fine needle aspiration cytology (FNAC) has been advised on the basis of nodular upper lobe opacities. The cytology smears revealed hypocellular granular material, while phase contrast and polarized light microscopy highlighted crystalline particles. History of silica dust exposure long back was available after the cytological evaluation, suggesting the diagnosis of pulmonary silicosis. X ray diffraction (XRD) crystallography was also possible on cytology smears, confirming zeolite nano particles of size as small as 40 - 50 nm as the concerned agent for the first time. Cytological evaluation by phase contrast and polarized light microscopy may be useful for the confirmation of silicosis, supplemented by clinical history and radiological evaluation. XRD on smears may help in determination of chemical nature and particle size.