Lets Build a Distillation Condenser for Nitric Acid

[darinventions]

Well Ill begin by saying that I've built two of these an it works great for making 60% or less nitric. the first one i made had a flaw that i corrected with the second one.Now a little bit about me. I joined the forum about a year ago. But I've been recovering an refining for a little over five years . i spent two years before that reading about how to refine an do it safely on this forum an a couple others. With that said i hold my own personal safety as number one above any amount of gold an you should hold your safety to the same standard .So lets get to the point...what were building here is a condenser..But you WILL have to build a fume hood to put the complete setup into an will need to build a scrubber for it as well. So don't worry about the scrubber at this point as i will post building it next... well there is no exact list of items that i can give you for your fume hood as your work space will be different from my own..so ill just show you I've done an used an you can alter the size an shape to fit your needs.. now as far as your fume hood go's you can be very creative with this. Here's a few that I've made..

 

[darinventions]

IMPORTANT !!!!! DO NOT AT ANY PIONT HOOK THIS SYSTEM UP TO HOUSE WATER... it is not designed for that kind of pressure..failure to use any kind of water pump besides low pressure water pumps can an most likely will result in serious injury or even death...HOT SULFURIC&HOT NITRIC ACID should always be handled with extreme care...make sure you test run the system an check for leaks before distilling...

 

[darinventions]

For your fume hood you can use 5/8or3/4plywood.. it works just fine for this..build your frame with 2x4's &you'll need a inside heighth of (44") to accommodate everything if you intend to make it like mine..and a lenth of (70") with a width of (18") put it together with deck screws(they hold up very well)...you'll need to cover the bottom with something that will handle exposure...(40mil pvc liner)you'll have to nail it in place..use 7/8"roofing nails for that an cover the heads with (alex plus caulk)if you cut the corners to make it fit then caulk them when your done...i used a old double pane,double hung,pvc vinyl window for the front...a lined the walls an inside top with cement backer board(Hardy Backer)but this is not necessary...the pan liner is a must though...if you can't find a window that will work ..you can improvise with some plexi glass(see pic with .pulvurizer) after the hood is made find a 2 1/8" holesaw for vacuum port...and a 1 1/4" for fresh air intake an water hoses(see picA-for vacuum port .....see picB-for freshair intake an water hoses)

 

[darinventions]

Once your done building the fumehood,you can add others stuff like light switches for a light,the vacuum ,&water pump...mine turns on all three at once..(see the very first pic,shows the homemade condenser)putting it all on one switch makes it very convenient ...so lets move on to the condenser...here's a list of everything you'll need an a pic of the parts.....2'-(1 1/2")pvc pipe,1-(1/2")cpvc pipe 8'long, 7-(1/2")cpvc elbow , 2-(1/2")cpvc mip adapter, 2-(1 1/2")pvc tee w/DWV sweep, 2 -(3/4")bushing reducer w/(1/2")female threads , 4- (1 1/2")to(3/4")bushing reducer, 1'of (1"O.D.)x(5/8"I.D.) rubber hose, 10'of(7/8"O.D.)x(5/8"I.D.)clear vinyl hose, 2-(1")hose clamps, 2-(2")hose clamps, 1-roll of Teflon Tape, 1-5gal.bucket , 1-80/155 GPH water pump , 1- can of pvc glue,

 

[darinventions]

Now for assembly, start by gluing the tee's onto the 1 1/2" pvc pipe..it go's together exactly as it is laid out,make sure the sweep's face each other an that one go's up an the other go's down ..now cut the 1/2"cpvc pipe at (45")long...next cut two (1")long pieces of the rubber hose...now make a mark on one end of the (1/2")cpvc pipe at(8")...an slip one of the (1") rubber hose bushing's onto the (1/2")cpvc until the outer part is at (8")...now slide it into the (1 1/2") pvc pipe assembly----now it fits lose---to fix this get out the roll of Teflon Tape an go around it about 12 times or so ,checking it for fit after 10 rounds until it almost doesn't fit,then give it two more rounds... now you'll need a small flathead screw driver to tuck it in place ...now turn it over to the other. end an do it all again except this time you'll need to tuck a little an then press the bushing in ,tuck &press... the objective is to get the bushing in without moving the other bushing out of place ...(you can use the 1/2"cpvc mip adaptor to assist in doing this..it gives more surfaces area to put your fingers ..an slides over the pipe just right)...in the list there are 2-(2")hose clamps --these are optional if you chose to make or need a retainer..see(picA2)

 

[darinventions]

Once your done setting the bushing in place we can move on to the water plumbing parts..(we'll refer to the part you just installed as the CONDENSING TUBE for future reference) go ahead an glue the other parts in place ..when you get to the threaded part(1/2"mip)put two rounds of Teflon Tape on it in the opposite direction of the threads an screw it in with a wrench good an snug(not too tight)then you can begin cutting the (1/2")cpvc pipe to the lenths needed to make your turns(this will be determined by what setup you have made)if you've made a horizonal unit then you'll want to copy what i made, if its a vertical unit then you'll need to make it a little different, just make sure you water pipes are facing down when your done...

 

[darinventions]

If you've made your setup for vertical operation then you'll need to make a multi-angled pipe like this...set your angle's to fit an mark each side of your connection from fitting to pipe so you'll know where to set it when you glue it together...

 

[darinventions]

Well i think we've made it to our big shopping list now...here's the items you'll need to to complete this project ...1-propane burner(camping stove burner) or a electric heating mantle (mantle's are expensive) 2-(1Lb.)propane bottles(not required if using mantle)(can refill these bottles to save $$)(i bought my refill adaptor at walmart in camping section ) 1-roll. of Heavy Duty Aluminium Foil (for foil bath) 1-500ml. (Or)1000ml. Distillation Flask 1-candy thermometer (they cost$4 an are good for up to 400°F ...2- catch receivers (for the fresh nitric to drip into) 1-small glass jar(to catch drips after use) 1-glass storage container (for all your distilled product) &about 20' of (12/2wire)to tie up the still ..(leave the insulation on the wire)i think its (picA)that shows around about how i wired it in place(and here's another pic --picA2)..you'll need a stovetop drip pan to put on top of the burner an that gives a place to set your distillation flask an also gives you something to attach your foil to

 

[darinventions]

For 500ml. distillation flask...cut a (1")long piece of the rubber hose you used earlier for your condensing tube...you'll need to lube it up on the inside with some spit(ha-ha)don't use oil---really use spit..do the same on the candy thermometer an slide the rubber onto it up to the 70°C mark(I'm not gonna lie this IS a pain to do) you don't want to use oil because it WILL contaminate your nitric.. now this will fit good an snug in your distillation flask so you can monitor your temp... you'll need to rap Teflon Tape in two places on the stem of your distillation flask..rap enough that it fits snug in the condensing tube...once that's done your almost ready to make some nitric..

 

[darinventions]

So here's the recipe i use...its not exact by no means..but. if your using a 500ml. flask you won't want to add much more of anything to this as you may have a boil over...an that will ruin your product ...IN THE EVENT that you do have a bad boil over and it clog's up the condensing tube..shut everything off,let cool,pull the condenser out,then pull the condensing tube out of condenser an replace with a new tube...(remember i said the first one i made had a flaw.).the flaw was i glued everything together ..so when this happened to me i had to throw the whole thing away an start from scratch ...that's when i came up with the idea of a removable condensing tube...anyway you can play with the portions a little ..like adding more nitrate an subtracting some water or sulfuric.. but with a 500ml. flask you really don't have much room for adjustment..i also included the run time..like i said before..this is not exact but it gives you a good idea of what to expect...

 

[darinventions]

So let me give a run down of what this means...start time is when i lit the burner...first drop is when the thermometer read 80°C an the FIRST drop of product came out...Change @121°C is when i swap catch receivers ,as the potency increases at this temp..END--i never let it get to the point of boil over(when you see about a 1/2"foam head forming in the flask its time to turn it off...Complete --you need to just leave it alone until the temp drops below 80°C an then you woukd be well served to put some heavy gloves on an empty out(pour out)the flask..i pour mine in a old dirty 5gal bucket(this will go out with your other waste)leave the receiving flask alone for about 5minutes after completion to catch additional drips of product ...then remove an place the glass jar there to catch what's left...

 

[darinventions]

So in the list of things you'll need i listed Aluminium Foil...this is for a foil bath(see pic--Foil Bath)the purpose of this is to increase the AIR temp inside the distillation flask to aid in distillation ...on average ill get 250to300ml. of product per run...you can use this product for anything you wish including Electrolyte for your Silver Cell . ...here's some pics of leftover product an it in use on silver.....i forgot to add that need to fill. you bucket 1/3 full of cold tap water an the rest with bagged ice for best results(it won't hurt the water pump one bit)and it lowers the change of losing product from off gassing(that's when the nitric is not full condensing back to a fluid) .....

 

[darinventions]

Well i think i covered everything here..ill begin posting my next one on the scrubber later this week or the beginning of next week....the product made with this system is what i use as Electrolyte in my SILVER CELL...here's a pic..ill be posting anothet pic of it before i harvest the silver crystals out of it and ill be holding a little competition on who can guess how much silver is in it..after melt weight..prize will be this condenser.... 8) ....i tried to load a data sheet on nitric acids reaction with plastics...it won't load...but anyway you can find some info easy enough with Google..all of them that I've found say that (CPVC) is inert...i would. still use some wisdom with this though an don't try to make (65% or stronger)nitric with this setup ...look at the pics in the beginning of this thead an you'll see that i have lab grade coil condenser for that ...

 

[g_axelsson]

Nice series of posts.

An electric heating mantle can easily and cheaply be built by the hobby refiner.
Do a quick google search for make your own heating mantle and you will find youtube videos and a lot of posts on other forums, on Sciencemadness for example.

Göran

 

[darinventions]

Well it looks like you men&women have work to do..if you have any questions. PM me an ill try my best to answer...i think i covered everything but i know that sometimes you have to improvise because some items may not be available where you live...if that is the case ...explain your situation an ill try to provide a solution....good luck..Dave