Uptake of aniline and nitrobenzene from aqueous solution by organo-zeolite

Adsorption mechanisms of toxic non-ionic organic contaminants (NOCs), aniline and nitrobenzene, with natural-zeolite andorgano-zeolite (OZ) were investigated in both batch and continuous systems. In batch tests, the adsorption capacity ofaniline and nitrobenzene onto natural zeolite surface is very low or almost nil but becomes significant upon modifying thezeolite surface by hexadecyltrimethylammonium (HDTMA). A partitioning mechanism is proposed to be responsible for the adsorption of NOCs onto OZ. The effectiveness of the partitioning mechanism is directly connected with hydrophobicproperties of the NOCs. The column tests were carried out as an indicator for continuous system. The breakthrough curveswere constructed for OZ/NOC system and the adsorption capacity of NOCs onto OZ under the present conditions weredetermined as 2.36 and 3.25 mg per gram of OZ, for aniline and nitrobenzene, respectively. A schematic model is proposedto account for the adsorption of NOCs onto OZ

Electrokinetic properties of clinoptilolite with mono- and multivalent electrolytes

In this study, electrokinetic properties of clinoptilolite have been determined. A series of systematic zeta potential measurements have been performed to determine the isoelectric point (iep) and potential determining ions (pdi), and the effect of mono- and multivalent salts such as NH 4 Cl, CaCl 2 , Al(NO 3 ) on the zeta potential of clinoptilolite. Clinoptilolite in water exhibits a negative surface charge and maintains this character even in very acidic conditions of pH 2–3. This reveals that clinoptilolite has no iep in the pH range of 2–12. H 3 þ and OH ions are the pdi for clinoptilolite. Excluding the trivalent Al 3þ cations, monovalent and divalent cations are not able to reverse the surface sign of clinoptilolite. This is attributed to the ion exchange ability of clinoptilolite and the strong specific adsorption of the Al counterions. A schematic adsorption model which accounts for the adsorption of mono- and multivalent ions in the electrical double layer of clinoptilolite is proposed

Production of trona concentrates using high-intensity dry magnetic separation followed by flotation

Soda ash, an essential raw material for major industries, such as the glass, chemicals, soap and detergents, pulp and paper, mining and water treatment industries, is traditionally produced by chemical and thermal treatment of trona ore. The treatment processes for trona ore are not only chemically expensive but also energy intensive. Hence, the production of a high-purity trona concentrate at a lower energy and operating cost is of considerable interest to the trona industry. In this study, we describe a possible two-stage process for concentrating trona ore, involving dry magnetic separation followed by flotation, to remove insoluble impurities from the trona ore. The results showed that a trona concentrate of 91.7% purity with a recovery 91.1% can be obtained by two-stage magnetic separation, which could be further improved to 98.1% purity at a recovery of 83.8% by subsequent flotation of the non-magnetic trona product. The purity of trona concentrate is limited by the particle size and impurity content of the trona ore. The operating parameters for magnetic separation and flotation have been identified to obtain an acceptable quality concentrate

The WHO global alliance against chronic respiratory diseases in Turkey (GARD Turkey)

In order to prevent and control non-communicable diseases (NCDs), the 61st World Health Assembly has endorsed an NCD action plan (WHA resolution 61.14). A package for essential NCDs including chronic respiratory diseases (CRDs) has also been developed. The Global Alliance against Chronic Respiratory Diseases (GARD) is a new but rapidly developing voluntary alliance that is assisting World Health Organization (WHO) in the task of addressing NCDs at country level. The GARD approach was initiated in 2006. GARD Turkey is the first comprehensive programme developed by a government with all stakeholders of the country. This paper provides a summary of indicators of the prevalence and severity of chronic respiratory diseases in Turkey and the formation of GARD Turkey