Metallurgy/Flotation question:
It is desired to float pyrite, FeS2, from coal. Describe a method by which this could be accomplished. In this description include all solution conditions and chemical additions required for the pyrite to be stable at the air/water interface. Clearly justify why flotation is either occurring or not for each solid type present.
If quartz, SiO2, were present in this system would it float with the FeS2 under the conditions you described above, why or why not?
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On a chromatographic column one meter in length, operating with an efficiency of 10,000 plates, the retention time of ?-chlorestne and ?-chlorestne are 4025 and 4100 seconds respectively. If these two compounds are to be separated with baseline resolution, can the desired separation be accomplished using this one meter column? The dead time of the column is 480 seconds.
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Eastown Industries conducted a Management of Change review for switching to a new propylene dichloride supplier. The propylene dichloride was purchased in railcar quantities and unloaded into a large storage tank, from which it was metered into 55 gal drums for sale to customers. During the Management of Change review, it was identified that the supplier sometimes used aluminum railcars for other products. The shift supervisor raised the question of what would happen if the propylene dichloride was received in an aluminum railcar and remained on the siding for a few days before unloading its contents into the storage tank. 9 Use the NOAA Chemical Reactivity Worksheet (CRW) as a resource to decide if the propylene dichloride is compatible with the al
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A sandstone has a porosity of 25% and permeability of 300 md. Calculate the surface area Sp, the specific surface area per unit pore volume.
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A liquid octane (C8H18) enters a combustion chamber of a gas turbine stationary at 1 atm and 25 °C, and burns with 300% of excess air that enters the chamber in the same state.
Determine the heat of combustion if the products come out at 226.85 °C (kJ/kg)
Determine adiabatic flame temperature (°C)
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A thermopane window consists of two pieces of glass each 0.1"
thick separated by a layer of dry,
stagnant air .4" thick.
• Find the resistance of a 4 ft × 3 ft thermopane window.
• Suppose the window is made by fastening an aluminum border .1"
thick all around the edge.
Find the total resistance for this configuration.
• As an alternative to the aluminum, we might use a border of .75"
thick white pine. Find the total
resistance for this configuration. (For white pine, "across the
grain", k = .087 Btu/hr ft °F).
• Calculate the heat loss for the two windows and compare with that
for a single pane of .1" glass.
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For my lab on depositing thin films on a surface via thermal evaporation I was asked hat would have happened if we had obtained different color metals on the samples after the thermal evaporation? The only thing I can think of is there was a leak in the vacuum chamber so a nonintended product could have formed via chemical reaction or chemical mixing. Can someone please give me a clearer answer. Thanks!
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In the design of large scale nitric acid project , explain in your own words
1. any consideration regarding heat recovery and,
2. the rationale for any decisions made on this aspect.
kindly explain in detail Thanks
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A spherical stainless steel (? = 7,800 kgm-3; c = 460 Jkg-1K-1; k = 17 Wm-1K-1; ? = 0.9) reactor of 1.0-m inner diameter and 1.0-cm wall thickness is filled with reactants (? = 1,100 kgm-3; c = 4,200 Jkg-1K-1) that are initially at 25 ?C. An exothermic reaction within the reactor generates heat uniformly at a temperature-dependent volumetric rate of Qoexp(-A/T), where Qo = 6 kWm-3, A = 85 K and T is the reactive mixture temperature in K. The exterior surface of the reactor is exposed to 25 ?C ambient air with a convective heat transfer coefficient of 20 Wm-2K-1, and also exchanges radiation with surrounding surfaces that are at 35 ?C. The reactant mixture is well stirred with a convective heat transfer coefficient of 250 Wm-2K-1 so that the temperature within the reactor is nearly uniform. You may neglect the thermal capacitance of the reactor wall and consider the instantaneous heat transfer rate through the reactor wall to be equal to the instantaneous rate of heat loss to the air and surroundings.
a) What is the temperature of the reactant mixture after 5 hours of process time?
b) What is the temperature at the outer surface of the reactor at that time?
c) What is the steady-state temperature of the outer surface of the reactor?
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1. The adsorbed ions comprising the Stern layer around a charged particle have the same charge (positive or negative) as the particle itself.
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True. |
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False, they have the opposite charge. |
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False, there are an equal number of positively and negatively charged ions in the Stern layer. |
2. Both ionic and nonionic surfactants can stabilize colloidal dispersions by adsorbing onto particle surfaces.
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True. |
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False, nonionic surfactants do not adsorb on particle surfaces. |
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False, surfactant adsorption always destabilizes colloidal dispersions by reducing the charge on the particles. |
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For Pulp and Paper class:
1) Purposes of coating and calendaring?
2) Major differences between aerated stabilization basin and activated sludge process?
3) Primary sludge vs secondary sludge?
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what is the most important information about scurbber (with out reaction) type packed pad . in point
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You are Plant Manager at the Hokomokee Nuclear Power Station in Moustafa County, which has two 1000 MWe PWRs and are planning the fuel cycle for the next ten years. You are beginning negotiations with your fuel supplier, Verma Fuels, and must choose between the 3.3% enrichment fuel you have been using and a new 5% enrichment fuel.
-Compare the environmental consequences of use of the two different fuels – i.e., consider which might generate more or less waste.
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