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The characterization and porous structure of raw and modified clinoptilolite as a sorbent has been investigated by nitrogen adsorption, X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, differential thermal analysis, scanning electron microscopy and atomic force microscopy methods. The nitrogen adsorption data revealed that the total pore volume and specific surface area were increased after modification. The nitrogen adsorption was used to determine percent of mesoporosity. The TG data show that 14 wt. % of clinoptilolite is lost after heating up to 1200 °C. Two types of porosities-primary porosity (microporosity) and secondary one (meso-and macroporosity) have been observed.

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Mining operations usually comprise a spread spectrum of environmental challenges, which are often unique to each mine site. This is due to the fact that mining activities, directly or indirectly, have an adverse impact on environment and ecology. For this reason, the environmental impact assessment (EIA) process has been developed for evaluation of the possible impact of mine development and operations on the environment, including the natural, social and economic aspects. In this article, an EIA methodology based on analytic network process and fuzzy simple additive weight (SAW) is proposed to formulate the environmental risks pertaining to mining projects. In the system of the proposed model, the importance weights are calculated by an ANP process. Then, fuzzy SAW is employed to evaluate the preference ratings of the alternatives. The merit of using fuzzy logic is to handle the inherent uncertainty in modelling an EIA problem by simplifying the sophisticated structure of the problem under consideration. The proposed model is utilised to assess the environmental impact generated by zinc and lead mining projects located in Zanjan, Iran to shape the future industrial and mining structure of the region. Finally, the environmental impacts are ranked from the most to the least risky.

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