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Zeolites are ordered crystalline materials with a promising performance for a wide range of applications such as catalysis, petrochemistry, environmental remediation, and medicine, but have scarcely been evaluated in Analytical Chemistry. Their unique and fascinating properties such as their high surface area, high adsorption capacity and molecular selectivity, chemical and thermal stability, ion-exchange capacity, low cost extraction and synthesis, and their easy modification, which provides a wide range of zeolite-based materials, make zeolites potential sorbents for extraction procedures. Therefore, in this review, we provide an overview of the current status of zeolites and zeolite-based materials used in extraction and microextraction techniques with reference to recent applications and highlight some of the novel advances. ; The authors would like to thank the Spanish Ministry of Economy and Competitiveness and European Union (FEDER funds) (project no. CTQ2016-79991-R) for financial support. P. Baile also thanks the Ministry of Education, Culture and Sports for her FPU grant (FPU14/04589).

In the past six years we have been intensively collaborating with the Chemistry Department of Addis Ababa University as well as Haramaya University to bust scientific knowledge related to zeolites and zeolite applications. Initially, we teamed up with geologists and government actors in the mining sectors; as a result we got access to natural zeolites from the north of the country, as well as other industrial minerals such as kaolin. In parallel we developed research activities in the use of zeolites as adsorbents and in catalytic processes related to environmental applications of necessity in Ethiopia. In the first part of this paper I will describe two examples of adsorption processes using mineral resources: one is a natural stilbite used to develop an adsorbent to remove fluoride from drinking waters; and the second one uses virgin kaolin to prepare a synthetic zeolite 4A that we used to remove chromium from tannery wastewaters. Finally, two catalytic examples will be described: in the first one we tackled the photocatalytic degradation of dyes from textile industries using Ti-modified natural and synthetic zeolites, and in the second one we used modified mordenites, both natural and synthetic, for the conversion of glucose into 5-HMF. ; ID is grateful to CSIC for her research leave at AAU and HU. The Spanish Research Council CSIC I-COOP+-2014 (COOPB20082) is acknowledged for funding. This work has been (partially) funded by the Spanish State Research Agency (AEI) and the European Regional Development Fund (FEDER) through the Project MAT2016-77496-R (AEI/FEDER, UE) and Project MAT2015-65767-P. Special thanks go to the members of the Molecular Sieves Group at ICP-CSIC. ; Peer reviewed

Conventional synthesis conditions for each type of zeolite are tabulated and reported by the International Zeolite Association Structure Commission (IZA) and most of them are synthesized from commercial reagents, but they can also be synthesized from industrial by-products rich in Si and/or Al. In zeolite synthesis from wastes, concentration of alkali source, temperature, reaction time, liquid/solid ratio and type of waste determine the textural properties, crystal structure, Si/Al ratio and ion exchange characteristics of the fabricated zeolite and its applications. This work summarizes the main methods that have been developed to synthesize zeolites using industrial wastes as Al and/or Si sources, the parameters of synthesis and the advantages and limitations of each synthesis process. The main characteristics and the applications of these synthetic waste zeolites are also reported. ; The authors are grateful for financial support from the Spanish Ministry of Economy, Industry and Competitiveness (AEI/MINECO) , the European Regional Development Fund and the Government of Navarra through projects MAT2016-78863-C2-1-R and PI017 CORRAL . MY thanks Government of Navarra for technologist recruitment. AG and EGFO also thank Santander Bank for funding through the Research Intensification Program.

There are presented results of technological experiments carried out in Water Treatment Plant Kúty. The goal of this study was to compare modified zeolite known as clinoptilolite (rich deposits of clinoptilolite were found in the region of East Slovakia in the 1980s) with the imported modified zeolite from deposit situated in Hungary. Klinopur-Mn and Klinomangan were used for removal of iron and manganese from ground water to meet the requirements of the Regulation of the Government of the Slovak Republic No. 496/2010 on Drinking Water. The materials observed exhibit different efficiencies of manganese removal from water, since the quality of the treated water play a major role (oxygen content and pH value). In the case of the removal of the iron from the water, the quality of the raw water is not a limiting factor; both materials removed Fe from the water to below the limit value (0.20 mg.l-1). ; Článok prezentuje výsledky technologických skúšok vykonaných v UV Kúty. Cieľom tejto práce bolo porovnať modifikované (povrchovo upravené) zeolity známe ako klinoptilolit (veľké nálezisko klinoptilolitu bolo objavené na Východnom Slovensku v 1980-tych rokoch) s dovážaným povrchovo upraveným zeolitom z náleziska v Maďarsku. Klinopur-Mn a Klinomangan boli použité pre odstraňovanie železa a mangánu z podzemnej vody na dosiahnutie limitných hodnôt pre pitnú vodu podľa Nariadenia vlády č. 496/2010 Z.z. Sledované materiály vykazovali rôznu účinnosť odstraňovania mangánu z vody, na účinnosť odstraňovania mala významný vplyv kvalita upravovanej vody (obsah kyslíka, hodnota pH). V prípade odstraňovania železa z vody kvalita surovej vody nie je limitujúcim faktorom, obidva materiály odstraňovali železo z vody pod limitnú hodnotu (0,2 mg.l-1).

Lubricant waste is one of the hazardous refuses which are regulated on the limit of lead content according to Government Regulations (Kep-51/MenLH/10/1995). Therefore, it is necessary to research for reducing the lead content. The purpose of this study is to understand the effect of adding adsorbents to decrease lead content in waste of lubricants taken from ships. The waste lubricant was recycled by adsorption using zeolite. Lubricant waste samples of 200 mL each were physically and chemically identified subjected to adsorption process using zeolite adsorbent whose concentrations (%w/w) were varied as follows: 7.5%, 13.25%, 14.25%, 15.75% and 17.5% with stirring speed of 150 rpm and contact time for 60 minutes. The best results were obtained at the adsorbent amount of 26.5 grams (concentration of 13.25%), for which lead content reduction reached 83%. The ANOVA F was obtained to be 13.42, and hence the study concluded that the amount of the adsorbent was related to the decrease in lead content.A B S T R A KPelumas bekas adalah salah satu limbah berbahaya yang dibatasi kadar timbalnya dalam Peraturan Pemerintah, sehingga perlu penelitian untuk menurunkan kadar timbal. Tujuan penelitian ini adalah untuk memahami pengaruh penambahan adsorben untuk menurunkan kadar timbal dalam pelumas bekas yang berasal dari mesin kapal. Pelumas bekas didaur ulang dengan adsorpsi menggunakan zeolit. Setiap sampel berisi 200 mL pelumas bekas yang telah diidentifikasi sifat fisika dan kimia-nya diadsorpsi menggunakan adsorben zeolit. Variasi konsentrasi zeolit (%w/w) yang digunakan yaitu: 7,5%; 13,25%; 14,25%; 15,75% dan 17,5% dengan kecepatan pengadukan 150 rpm dan waktu kontak 60 menit. Hasil terbaik diperoleh pada jumlah adsorben 26,5 g (konsentrasi 13,25%) dengan penurunan kadar timbal mencapai 83%. Faktor F pada hasil ANOVA adalah 13,42. Dengan demikian dapat disimpulkan bahwa terdapat korelasi antara konsentrasi adsorben dan penurunan kadar timbal.

[EN] In the last few years, important efforts have been made to synthesize so-called "multipore" zeolites, which contain channels of different dimensions within the same crystalline structure. This is a very attractive subject, since the presence of pores of different sizes would favor the preferential diffusion of reactants and products through those different channel systems, allowing unique catalytic activities for specific chemical processes. In this Review we describe the most attractive achievements in the rational synthesis of multipore zeolites, containing small to extra-large pores, and the improvements reported for relevant chemical processes when these multipore zeolites have been used as catalysts. ; Financial support by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat, MAT2012-37160, MAT2012-31657 and Intramural-201480I015 is acknowledged. ; Moliner Marin, M.; Martínez, C.; Corma Canós, A. (2015). Multipore zeolites: synthesis and catalytic applications. Angewandte Chemie International Edition. 54(12):3560-3579. https://doi.org/10.1002/anie.201406344 ; S ; 3560 ; 3579 ; 54 ; 12

This is the peer reviewed version of the following article: Angew. Chem. Int. Ed. 2018, 57, 15330 15353, which has been published in final form at https://doi.org/10.1002/anie.201711422. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Since the early reports by Barrer in the 1940s on converting natural minerals into synthetic zeolites, the use of precrystallized zeolites as crucial inorganic directing agents to synthesize other crystalline zeolites with improved physicochemical properties has become a very important research field, allowing the design, particularly in recent years, of new industrial catalysts. This Review highlights how the presence of some crystalline fragments in the synthesis media, such as small secondary building units (SBUs) or layered substructures, not only favors the crystallization of other zeolites with similar SBUs or layers, but also permits control over important parameters affecting their catalytic activity (chemical composition, crystal size, or porosity, etc.). Recent advances in the preparation of 3D and 2D zeolites through seeding and zeolite-to-zeolite transformation processes will be discussed extensively in this Review, including their preparation in the presence or absence of organic structure-directing agents (OSDAs). The aim is to introduce general guidelines for more efficient approaches for target zeolites. ; This work has been supported by the Spanish Government (MINECO through "Severo Ochoa" (SEV-2016-0683) and MAT2015-71261-R), by the European Union through ERC-AdG-2014-671093 (SynCatMatch), and by the Fundacion Ramon Areces (through the "Life and Materials Science" program). ; Li, C.; Moliner Marin, M.; Corma Canós, A. (2018). Building zeolites from precrystallized units: nanoscale architecture. Angewandte Chemie International Edition. 57(47):15330-15353. https://doi.org/10.1002/anie.201711422 ; S ; 15330 ; 15353 ; 57 ; 47 ; Cundy, C. S., & Cox, P. A. (2005). The hydrothermal ...

This work describes the synthetic procedures developed to obtain zeolite X (NaX), zeolite A (LTA) and sodalite (SOD) using aluminum saline slag waste (AlSSW) as aluminum source in a two-step hydrothermal method involving alkaline extraction of Al, with separation of the residual waste, and hydrothermal treatment at low temperatures and long reaction times. Use of the mother liquor obtained after filtration and separation of the zeolite is also analyzed in the alkaline extraction of Al. The synthetic parameters that determine the type of zeolite, purity, crystallinity, specific surface area, pore size and pore volume include the Si/Al molar ratio, pH, nucleation temperature and time, and crystallization temperature and time. These critical parameters were studied and determined to synthesize NaX, LTA and SOD as individual phases. The materials obtained were characterized by X-ray diffraction, scanning electron microscopy and N2 adsorption/desorption measurements at −196 °C. The characteristics of the best zeolites obtained are similar to those of IZA references and the specific surface areas are in the range of commercial ones: NaX ranges from 450 to 500 m2/g and LTA from 250 to 300 m2/g. The results show that it is possible to synthesize zeolites from AlSSW, thus allowing these materials to be applied as promising adsorbents and catalysts. ; The authors are grateful for financial support from the Spanish Ministry of Economy, Industry and Competitiveness (AEI/MINECO), the European Regional Development Fund (ERDF) and the Government of Navarra through projects MAT2016-78863-C2-1-R and PI017-PI039 CORRAL.