platinum extraction from different secondary sources has been experimentally tested by many researchers. in this article, dissolution of platinum in aqua-regia solution from two types of spent catalysts (reforming and nitric acid production) was kinetically studied. a variety of kinetic models for heterogeneous solid-liquid reactions, including homogeneous diffusion model, shrinking core model,...

Fenton oxidation, an advanced oxidation process, is an efficient method for the treatment of recalcitrant wastewaters. Unfortunately, it utilizes H2O2 and iron-based homogeneous catalysts, which lead to the formation of high volumes of sludge and secondary pollutants. To overcome these problems, an alternate option is the usage of heterogeneous catalyst. In this study, a heterogeneous catalyst ...

poly (n-bromosuccinimide) (pnbs) as a mild, efficient, non-acidic, polymeric and heterogeneous catalyst was applied for simple conversion of epoxides into thiiranes by treatment with kscn or (nh2)2cs at room temperature. aliphatic and aromatic epoxides converted into their corresponding thiiranes under mild conditions. all reactions proceeded in short reaction times and afforded the correspondi...

cobalt hydrogensulfate is an efficient catalyst for the condensation of β-naphthol, aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione at 120 °c to afford 9,9-dimethyl-12-phenyl-8,10,11,12-tetrahydro-9-h-benzo[a]xanthen-11-one derivatives in high yields. also, polycondensation reactions of phenols with phthalic anhydride were carried out in the presence of cobalt hydrogensulphate under so...

Background: The purpose of this study is to fabricate inexpensive in-house low cost homogeneous and heterogeneous human equivalent thorax phantom and assess the dose accuracy of the Treatment Planning Systems (TPS) calculated values for different lung treatment dosimetery. It is compared with Thermoluminescent Dosimeter (TLD) measurement. Materials and Methods: Homogeneous and heterogeneous tho...

Catalytic synthesis can be achieved by using either homogeneous or heterogeneous organometallic complexes, or homogeneous enzymatic biocatalysts. However, each of these methods offers advantages and disadvantages that must be balanced cautiously. Homogeneously catalyzed reactions are highly efficient in terms of selectivity (i.e. regioselectivity, enantiomeric excesses) and reaction rates, due ...

Mahmoud Zarei was born in Hamedan, Iran in 1986. He received his B.Sc. in Pure Chemistry (2010) from Islamic Azad University Arak and M.Sc. in Organic Chemistry (2013) at Bu-Ali Sina University, Iran. In addition, He received his Ph.D. in Organic Chemistry (2017) under the supervision of Prof. Mohammad Ali Zolfigol. He is currently working towards his Postdoctoral under the supervision of Prof....