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Functionalization of natural zeolites (NZ) with cationic surfactants drastically alters the surface chemistry of zeolite and opens new applications possibilities for water treatment: adsorption of pharmaceuticals, pesticides, dyes, etc. The use of surface modified natural zeolites (SMNZs) could be a reliable approach for water treatment, as they can simultaneously remove cations, anions, and/or non-ionized molecules. The main advantages of the NZs, as starting materials, are their abundance in nature, low-cost and good stability. However, the main drawback is a potential instability of surfactant at the zeolite surface. Literature data showed that a certain amount of surfactant can be removed from the zeolite surface depending on experimental conditions, which could have a negative impact on water quality. To increase SMNZs stability and abate possible negative effects on the environment, it is suggested to use different novel types of surfactants (Reeve et al., 2018 and references therein). For these reasons, a zeolite-rich tuff IZ CLI (Turkey) with clinoptilolite as the main component (79%) has been modified using two cationic surfactants such as Cetylpyridinium chloride (CPyCl) and Arquad®2HT-75 (ARQ), the latter with two hydrocarbon chains. The bilayer composites (B), CPyCl-B and ARQ-B, were prepared using the method of fast functionalization (de Gennaro et al., 2016). To test the stability of composites, 1 g of CPyCl-B or ARQ-B was washed with 2 l of distilled water. Z-potential (Zetasizer Nano ZS90, Malvern Instruments) was measured for unmodified tuff as well as for composites before and after washing. Z-potential for IZ CLI has shown a negative value (-37.9 mV). The formation of a bilayer was confirmed by the inversion of Z - potential values which turned to positive for both composites CPyCl-B and ARQ-B (+37.7mV and +36.1mV, respectively). After extensive washing of composites, Z - potential of CPyCl-B has dropped to -7.9 mV indicating a significant loss of

The present research deals with the evaluation of a clinoptilolite-rich rock, occurring in the Nizny Hrabovec deposit (Slovakia), for high-value technological applications based on sorption and in vitro release of nonsteroidal anti-inflammatory drugs (i.e., ibuprofen sodium salt). This georesource was surface modified (SMNZ) using four cationic surfactants. Results demonstrate that ibuprofen sorption is very fast and SMZNs can sorb up to (similar to)26 mg/g of drug as a function of the type of counterion and morphology of surfactant, as well as the hydrophobicity and molecular structure of the drug. Maximum sorption capacities observed for all SMNZs are fully comparable to other adsorbent carriers usually used for removal of contaminants in wastewaters. Sorption of ibuprofen is controlled by a dual mechanism: external anionic exchange and partition into the hydrophobic portion of the patchy bilayer. A prompt drug release in simulated intestinal fluid (SIF) was also observed, making this natural material also suitable to provide rapid soothing effects in potential pharmacological applications. Comparing the results of this study with other recent investigations, a good technological performance of clinoptilolite-rich rock can be inferred despite the relatively low zeolite content ((similar to)56 wt.%).

Clays and clay minerals are one of the important groups of materials that are widely used in environmental cleanup applications. The natural clay minerals are hydrophilic in nature, and hold high chemical stability and cation exchange capacity. Owing to the native electronegative surface properties and cation exchange capacities, natural clay minerals are good adsorbents of heavy metal cations and many other cationic organic contaminants. The modification of clay minerals can significantly improve their surface properties that consequently increase their contaminant removal capacities and efficiencies. The current chapter presents a brief overview of various clay modification and surface engineering methods, and discusses how the resultant modified clay products can remediate various environmental contaminants.

Protohistoric metal objects coming from the archaeological sites of Pontecagnano (Salerno, Italy) and Striano (Naples, Italy), preserved in the Pontecagnano National Archaeological Museum and the Paleontological Museum of Naples University “Federico II” have been studied by means of an archaeometric approach. A multi-analytical procedure including X-ray powder diffraction (XRPD), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), micro X-ray fluorescence (µ-XRF) and lead isotope ratio mass spectrometry (LIRMS), was used to characterize these objects thus providing hypotheses on the possible provenance of metallic raw materials. The investigated samples are represented by lead, silver, copper and tin bronze-based objects. Corrosion processes affecting the bronze objects were recognized as well as crusts and patinae at different stages of evolution. LIRMS analyses suggested that most of Pontecagnano artifacts were manufactured with metals from southern Tuscany, where important metal reserves were located. On the other hand, due to the limited number of samples, the provenance of the Striano objects cannot be unambiguously identified although data so far available suggest a Sardinian source.

Introduction Ion-exchange capacity represents a very important property of natural zeolites and has been widely investigated for environmental remediation and drug delivery (Mercurio et al., 2018 and references therein). Thanks to this property, zeolite can be surface modified via adsorption of long-chain cationic surfactants, providing an organo-mineral composite known as Surface Modified Natural Zeolite (SMNZ) able to sorb specific molecules by anion-exchange and partition mechanisms (Farías et al., 2010; Mercurio et al., 2018). This study aims to test the technological performance of a surface modified clinoptilolite-rich rock in the loading and in vitro release of ibuprofen sodium salt (IBU), in order to evaluate its possible use in high-value technological applications based on the sorption of non-steroidal anti-inflammatory drugs (NSAIDs). Experimental Methods A clinoptilolite-rich rock (CLI) from an economic deposit of zeolite located in the East-Slovakia basin (Nižný Hrabovec) has been surface modified using four cationic surfactants, namely cetylpyridinium chloride (CC), benzalkonium chloride (BC), hexadecyltrimethylammonium chloride (HC) and bromide (HB). Briefly, CLI (clinoptilolite content ~55.7 wt%) was added to a surfactant solution with an initial concentration equivalent to 200% of the external cation exchange capacity (ECEC) of starting material (~0.119 mEq/g). The so formed SMNZs (labelled CLI_CC, CLI_BC, CLI_HC and CLI_HB) were used to carry out IBU equilibrium sorption isotherms and loading/release kinetic tests according to Mercurio et al. (2018). Experimental points were fitted using several mathematical models, which non-linear fitting parameters and applicability were evaluated by considering determination coefficient (R2) and Bayesian Information Criterion (BIC). Further details about mineralogical and technological characterization of starting material, SMNZs preparation and mathematical modeling of sorption/release profiles are reported in

Two different surfactants, cetylpyridinum chloride (CP) and hexadecyltrimethylammonium bromide (HDTMA) were used to modify the surface of a natural zeolite - phillipsite (PHI) and adsorption of ochratoxin A (OCHRA) was investigated. Adsorption experiments were done with different amounts of adsorbents and with different initial OCHRA concentrations at pH 3 and pH 7. Results showed that modification of phillipsite surface with CP and HDTMA significantly improved adsorption of OCHRA in comparison to unmodified phillipsite. CP modified phillipsite showed similar adsorption behavior as HDTMA modified phillipsite. The highest adsorption capacity for OCHRA was obtained with CP modified phillipsite at pH 3.