Integration of Geological, Geochemical, Mineralogical and Remote Sensing Data for Studying Zeolite Deposits of Al-Ahyuq-Taiz, Yemen

Zeolite deposits crop out at Al-Ahyuq area, and lies at about 89 km southwest of Taiz city. It is one of the most important zeolite localities in Yemen. The study area is covered by the Yemen volcanic group. X-Ray Diffraction (XRD) analyses showed that clinoptilolite is the major type of Al-Ahyuq zeolites with high purity. Chemical analysis shows that the studied zeolitic tuff samples have silica content ranging from 63.10 wt% - 71.1wt% with an average 68.69 wt%, Fe2O3 [as total iron] with an average 2.38wt%, MgO with an average 0.44 wt% and TiO2 with an average 0.17wt%. These chemical properties of Al-Ahyuq zeolite deposits are with low impurities content such as CaO and MgO, compared to those deposits found in other countries around the world. The chemical and mineralogical studies support that the zeolite minerals of the Al-Ahyuq area formed by subaerial hydrothermal alteration of the parent volcanic glass. The ASTER bands as false colour composite (1-R, 2-G, 3-B), and band ratios 3/9 and 4/6 highlighted area of zeolite deposits dominated as bright pixels. The band ratio combination 4/6-R, 2/1-G and 3/2-B is effective in mapping of Al-Ahyuq zeolitic tuffs. Spectra after being resampled to ASTER VNIR+SWIR bands of the study area comparing with the USGS library spectra of zeolite – clinoptilolite shows almost identical and confirmed that clinoptilolite is the major of zeolite deposits in Al-Ahyuq area. Chemical and mineralogical investigation of the Al-Ahyuq zeolite (clinoptilolite) deposits recommends many important agricultural, environmental, and industrial applications. Keyword: Zeolitic tuff; clinoptilolite; XDR; XRFS; ASTER data; band ratio

Impact of inorganic powder additives on the size and morphology of pellets of the microscopic filamentous fungus Aspergillus niger

This paper has been focused on the impact of the set of microcrystal water-insoluble inorganic additives to dimension characteristics of pellets of the microscopic filamentous fungus Aspergillus niger. The selection of powder substances included montmorillonite clay mineral, silicon dioxide, iron oxide, one zeolitic tuff with mineral clinoptilolite as its main component, three synthetic zeolites, Na-mordenite, NaY and Na-ZSM-5, and titanium dioxide. This group is comprised of substances that are often components of various natural waters (including contaminated waters) and also frequent components of soil. Exceptions are synthetic zeolites and titanium dioxide. The impact of aforementioned substances was monitored on four Aspergillus niger strains isolated from soils at four Slovak locations, markedly differing in soil reaction values. Three of these soil samples have been affected by considerable contamination due to previous mining activities. Clay mineral montmorillonite reduced the size of the pellets regardless of the origin of strains, while the impact of other inorganic substances was either weak or variable depending on the type of inorganic substance and source location of the strains. The impact of natural zeolitic tuff was also similar, however, less significant.

Removal of Carbamazepine onto Modified Zeolitic Tuff in Different Water Matrices: Batch and Continuous Flow Experiments

Carbamazepine (CBZ) is the most frequently detected pharmaceutical residues in aquatic environments effluent by wastewater treatment plants. Batch and column experiments were conducted to evaluate the removal of CBZ from ultra-pure water and wastewater treatment plant (WWTP) effluent using raw zeolitic tuff (RZT) and surfactant modified zeolite (SMZ). Point zero net charge (pHpzc), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier Transform Infrared (FTIR) were investigated for adsorbents to evaluate the physiochemical changes resulted from the modification process using Hexadecyltrimethylammonium bromide (HDTMA-Br). XRD and FTIR showed that the surfactant modification of RZT has created an amorphous surface with new alkyl groups on the surface. The pHpzc was determined to be approximately 7.9 for RZT and SMZ. The results indicated that the CBZ uptake by SMZ is higher than RZT in all sorption tests (>8 fold). Batch results showed that the sorption capacity of RZT and SMZ in WWTP effluent (0.029 and 0.25 mg/g) is higher than RZT and SMZ (0.018 and 0.14 mg/g) in ultrapure water (1.6–1.8 fold). Batch tests showed that the equilibrium time of CBZ removal in the WWTP matrix (47 h) is much longer than CBZ removal in ultrapure water. The sorption capacity of RZT & SMZ in WWTP effluent (0.03, 0.33 mg/g) is higher than RZT and SMZ (0.02 and 0.17 mg/g) in ultrapure water (1.5–2 fold) using column test. This study has clearly demonstrated that the performance of RZT and SMZ is more efficient for the removal of CBZ from realistic wastewater than ultrapure water. It is evident that the surfactant modification of RZT has enhanced the CBZ removal in both matrices.

Properties of lightweight concrete blocks with waste zeolitic tuff

In general, three different types of wall products commonly used in the building sector, namely traditional clay brick, lightweight concrete blocks and aerated concrete, are produced with pumice and perlite. We have created alternative block walls with Bayburt stone (BS) containing zeolite, namely lightweight concrete masonry blocks (LCMBs). BS was an aggregate, cement dosages ranging from 150 to 250 kg/m3 were a binder, 3 different type of superplasticizers were selected as a chemical additive. Compressive strength, water absorption, unit weight, elevated heat effect, freeze-thaw resistance, capillary water absorption and thermal conductivity tests were performed.