background: this research studied the feasibility of a simple method for extracting gold from central processing units (cpus) of computer circuit boards without solvent. methods: ceramic and composite cpus of computer circuit boards were used. gold was extracted using a hydrometallurgical method in six stages: grinding of cpus, leaching in nitric acid, leaching in aqua regia, removing the exces...

A new approach is described for the recovery of precious metals (PMs: Au, Pd and Ag) with >99% efficiency from aqueous solution utilising biogas produced during the aerobic growth of Klebsiella pneumoniae. Gold was recovered from electronic scrap leachate ( approximately 95%) by this method, with some selectivity against Cu. The recovered PM solids all contained metal and sulphur as determined ...

Despite recent exciting progress in catalysis by supported gold nanoparticles, there remains the formidable challenge of preparing supported gold catalysts that collectively incorporate precise control over factors such as size and size-distribution of the gold nanoparticles, homogeneous dispersion of the particles on the support, and the ability to utilize a wide range of supports that profoun...

the origin of the proterozoic choghart iron oxide deposit in the bafq mining district of central iran has been the subject of a long-standing dispute. some authors believe that it was formed from magma, while others suggest metasomatic replacement of preexisting rocks. the present study on the basis of new oxygen isotope, ree and geochemical data concludes that neither of these two hypotheses c...

The Zarshuran Carlin-like gold deposit is located at the Takab Metallogenic belt in the northern part of the Sanandaj-Sirjan zone, NW Iran. The high-grade ore bodies are mainly hosted by black shale and cream to gray massive limestone along the NNE-trending extensional fault/fracture zones. The aim of this investigation was to determine and separate the gold mineralized stages based on the surf...

 Background: This research studied the feasibility of a simple method for extracting gold from central processing units (CPUs) of computer circuit boards without solvent. Methods: Ceramic and composite CPUs of computer circuit boards were used. Gold was extracted using a hydrometallurgical method in six stages: grinding of CPUs, leaching in nitric acid, leaching in aqua regia, remov...

We exploit the strong plasmon resonance of gold nanoparticles in the catalytic decomposition of CO to grow various forms of carbonaceous materials. Irradiating gold nanoparticles in a CO environment at their plasmon resonant frequency generates high temperatures and strong electric fields required to break the CO bond. By varying the laser power, exposure time, and gas flow rate, we deposit amo...