Questions tagged [chemical-engineering]

For questions about processes in commercial chemical manufacturing.

28 questions with no upvoted or accepted answers
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4
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3answers
168 views

Recycle unreacted ethene

The question is this: You want to make oxirane from ethene and oxygen gas: $$\ce{2 C2H4 + O2 -> 2 C2H4O}$$ The flow into the reactor is constant at $\pu{200kmol/h}$ of $\ce{C2H4}$ and $\pu{...
3
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0answers
110 views

Why do we want to operate at dew point or bubble point when doing flash calculations?

I'm trying to dimension a flash drum for a separation between water and isobutane. I now the total inlet flow (F), the composition of the inlet flow ($z_1$ for isobutane and $z_2$ for water) and the ...
3
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0answers
70 views

Calculating temperature of partial condenser, flash calculations

The iterative method I have learned to make flash calculations for a binary system where I know the inlet feed (F [mol/s]), total composition of the two components ($z_1$ and $z_2$), the amount of the ...
3
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0answers
140 views

Do theoretical plates required to obtain a pure product decrease under vacuum distillation?

For this question I am using Ethanol as an example. The following is the vapor-liquid equilibrium diagram for Ethanol under atmospheric pressures. Under reduced pressures do the number of theoretical ...
3
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0answers
105 views

Determine whether the tank will overflow with mass flowrate

Hydrocarbon mixture ($\pu{20 mol\%}$ $\ce{CH4}$ and the balance is $\ce{C2H6}$) enters a tank at a velocity of $\pu{1 m/s}$ and is withdrawn at a rate of $\pu{2 kg/s}$. The tank is initially one ...
3
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0answers
734 views

What is the relation between pressure and chemical potential?

I know that in a two-component gas-liquid system (for simplicity) the chemical potential $\mu_i$ ($i=1,2$) and total pressure $p$ can be defined by $$\mu_i=\left(\frac{\partial U}{\partial N_i}\right)...
2
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0answers
78 views

Why will A atoms diffuse from β phase to α phase and B atoms from α phase to β phase?

At the initial compositions 1 and 2 of $α$ and $β$ respectively the chemical potentials of A and B atoms in each phase can be found by extrapolation of the tangents to the free energy curves at 1 and ...
2
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0answers
139 views

Is there a chemical reaction between tungsten carbide and acrylic?

My company machines acrylic (Poly(methyl methacrylate) $\ce{(C5O2H8)_n}$), and notices that tungsten carbide tools break down quickly compared to high-speed steel, even though carbide is harder and ...
2
votes
1answer
620 views

What are glues/adhesives for cardboard boxes/crates made of?

Open cardboard boxes/crates, often for foodstuffs, are often glued to hold their shape. What is the glue/adhesive made of? I ask to know if it is biodegradable, such that it is suitable for ...
1
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0answers
31 views

Recycling flow if the chemical process of acetylene and hydrocyanic acid

I'm having some issues trying to solve this problem, because the concentration of inert in the recycling flow that I calculated is bigger that the concentration of the inert that is enterying to the ...
1
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0answers
55 views

Ideal CSTR mixing assumption

Sorry if this seems like a silly question but it has me confused a lot. So I have just started taking Chemical Reaction Engineering, and was studying about continuous-stirred tank reactor (CSTR). So ...
1
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0answers
110 views

The Use of AI and Machine Learning in Organic Chemistry

I am trying to do a bit of research into the current use of machine learning in chemical industry. I've been told my original question was too general so I'll try to be more specific about what I'm ...
1
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0answers
43 views

Definition of throughput

I wonder what's the exact meaning of throughput in chemistry synthesis, eg. in organic synthesis or production of pharmaceutical products. For instance, what are their units? How are they measured? I'...
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0answers
84 views

Correct Generalization for Adair Equation?

I know how to derive the Adair Equation for n binding sites the long way, writing n+1 mini equations and linking them to relate all sub $K_b$ values to $K_{b-intrinsic}$. Tried to find a general ...
1
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0answers
392 views

Impact of pH? Change in Binding Affinity of protein-ligand complex based on pH and Kd?

When the $\mathrm{pH}$ was $5.0$, the temperature was $\pu{25 °C}$,the $K_\mathrm{D}$ was $\pu{5 μM}$, and [L] was equal to $K_D$, the protein(s) were half bound. Question considers half bound ...
1
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0answers
64 views

Reference conditions for balances on nonreactive processes

In one of the examples in my book (Elementary Priniciples of Chemical Processes) where I am asked to calculate the rate of heat input required to heat a stream of methane and air from 20°C to 300°C, ...
1
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0answers
25 views

Can diamond be grown on copper wires using chemical vapor deposition techniques?

I am asking this as a follow-up to another question I asked earlier. It is regarding how to make higher voltage transformers. Diamond is a good dielectric material and would be good for using as a ...
1
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0answers
71 views

PTFE-to-PTFE or PTFE-to-Copper pressure seal

I am currently working on an engineering project with a friend. Without giving too much away, I have two parallel strips of Zirconium-Copper alloy sandwiched between an upper and lower piece of smooth ...
0
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0answers
18 views

Literature recommendation - non-stationary heat transfer in porous solids

I am trying to calculate a non-stationary heat transfer to a porous spheres by conduction. These spheres are placed in a thin metal tubes with a known heat capacity. Hot/cold air (or similar gaseous ...
0
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1answer
18 views

Non-RSPO MB glycerin vs RSPO-MB glycerin

Does non-RSPO-MB glycerin function differently than RSPO-MB glycerin? For example in a cosmetic serum /lotion?
0
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0answers
36 views

Which reaction is happening in the preparation of sulfuric acid through contact process?

I've read that in the preparation of $\ce{H2SO4}$ through the Contact process, on the absortion tower, the gas $\ce{SO3}$ is getting in contact with $\ce{H2SO4} (l)$ , because adding $\ce{SO3}$ to $\...
0
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0answers
33 views

Vapor - Liquid Equilibrium (VLE)

Most fundamental equation for VLE is $$ \mu_i^L = \mu_i^V $$ It states that for every component chemical potential must be equal in both liquid and vapor phase at equilibrium. However, in my thermo ...
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0answers
25 views

How much energy is required to liquify oxygen?

Does anyone know where I can find some documentation of a real-world liquification process, and the energy costs? I can calculate the heat that must be removed from O2 gas to get to liquid, but how ...
0
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0answers
494 views

Thermodynamic and Transport properties input files for Chemkin

I am using Chemkin pro 2009 version. I want to model a decomposition+combustion reaction on my catalyst in a plug flow reactor.So I'll need to create my own Thermodynamic and Transport Properties file ...
0
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0answers
63 views

X-ray bombardment of CaCl2 and its resultant chemical changes

If one were to take $\pu{1 mol}$ of pure liquid Calcium Chloride (at $\pu{600 ^\circ C}$) and bombard it with $\pu{7.65 \times 10^{14} Ci}$ ($\pu{2.83 \times 10^25 particles}$) of x-rays ($\pu{75 keV}$...
0
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0answers
40 views

Chloride Process TiO2 recovery

In the chloride process (the process used to create titanium oxide from titanium ore), how is TiO2 collected? What prevents the TiO2 from building up on the walls of the reactor chamber? It's my ...
0
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0answers
39 views

Reaction between chlorine gas and oxygen at 600 degrees Centigrade

Chlorine gas will not normally react with oxygen gas directly at STP. However, would the two react at standard pressure and 600 degrees Centigrade?
0
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1answer
36 views

How to relate equilibrium constant and equilibrium conversion?

For the following gas phase reaction: $$ A\leftrightarrow B $$ The concentration equilibrium constant ($K_c$) can be expressed as: $$ K_c = \frac{c_B}{c_A} = \frac{\frac{F_B}{\vartheta}}{\frac{F_A}{\...