in this study, effects of solid concentration, temperature, and initial fe2+ concentration on bioleaching of sulfide mineral (chalcopyrite) obtained from sarcheshmeh copper mine in the region of kerman located in the south of iran were investigated. a mesophilic iron oxidizing bacterium, acidithiobacillus ferrooxidans has been isolated from a typical chalcopyrite copper concentrate of the menti...

Semihydrogenation of 2-methyl-3-butyn-2-ol (MBY) was studied in a 5 m tube reactor wall-coated with a 5 wt % Pd/ZnO catalyst. The system allowed for the excellent selectivity towards the intermediate alkene of 97.8 ± 0.2% at an ambient H2 pressure and a MBY conversion below 90%. The maximum alkene yield reached 94.6% under solvent-free conditions and 96.0% in a 30 vol % MBY aqueous solution. Th...

A new simple, sensitive and precise green analytical procedure using an automated packed-reactor derivatization technique coupled with on-line solid-phase enrichment (SPEn) has been developed and evaluated to determine trace levels of methotrexate (MTX). The method was based on injection of MTX into a flowing stream of phosphate buffer (0.04 M, pH 3.4), carried through the packed oxidant reacto...

Gasification has become an attractive technology that is capable of producing a rich syngas from a range of biomasses and other fuels. This syngas can then be further processed into liquid fuels through Fischer-Tropsch processes to provide an alternative to current fossil fuels or to provide local markets with a competitive fuel. The purpose of this study was to construct a four-inch bench scal...

The main aim of this work was to evaluate the efficiency producing caproic acid and other volatile fatty acids using a co-digestion between cheese whey sewage sludge in continuous reactor. effect two different feeding regimes (one per day) three hydraulic retention times (HRT) (15, 10 6 days) on organic production were studied. optimal conditions for process days HRT, 2 cycles day, reaching max...

Lewis acidic zeolites are used to synthesize unsaturated dicarboxylic acid esters via aldol condensation of keto esters. Hafnium-containing BEA (Hf-BEA) zeolites catalyze the condensation of ethyl pyruvate into diethyl 2methyl-4-oxopent-2-enedioate and diethyl 2-methylene-4oxopentanedioate (an itaconic acid ester analogue) with a selectivity of ca. 80% at ca. 60% conversion in a packed-bed reac...

background: sulfur compounds must be removed from petroleum because they contribute to environmental pollution. a strong alkaline solution such as caustic soda is used to remove these compounds. this spent caustic has high values for chemical oxygen demand (cod) concentration, ph and total sulfur. in this study, the regeneration and treatment methodology of sulfidic spent caustic was investigat...

the nanoparticles of ti and tio2 have attracted extensive research interest because of their diverse applications in, for instance, catalysis, energy conversion, pigment and cosmetic manufacturing and biomedical engineering. through this project, a one-step bulk synthesis method of electromagnetic levitational gas condensation (elgc) was utilized for the synthesis of monodispersed and crystalli...

NH3-Selective Catalytic Reduction (SCR) is applied worldwide to DeNOx of combustion exhausts from stationary and mobile sources, but a greater DeNOx activity at low temperatures is desired to meet forthcoming restrictive legislations. We have obtained high NO reduction efficiencies at 200 – 300 °C over commercial V-based and Fe-exchanged zeolite catalysts by reacting NO with both ammonia and ni...

A high chlorinated alumina catalyst obtained by treating Pt/γ-Al2O3 (0.25 wt. % Pt) samples with two mixtures of CCl4/N2 and CCl4/N2/H2 was tested for the hydroisomerization of C6 alkane. The conversion of n-hexane feed was diluted with hydrogen performed with different H2/HC ratios at various temperatures, liquid hourly space velocities (LHSVs) and 3MPa total pressure. The catalyst introduced ...