Fractional Distillation

In this section we will focus on a fractional distillation protocol something of which is not so common. First body removal. The actual boiling points used in isolating specific distillation output can be very tricky at first. And sometimes nearly impossible to gather through a short path head without massive trails on contamination. Hence the difficulty of distilling curatives through a thin film requiring numerous passes. This can be simplified with a mantle and the process can be dialed very well. As a mantles create vapor pressure from operation and other distillation hardware does it. It funnels vapor molecules through a complex and contaminated path (if not rigorously cleaned between flushes) when using wiped film and thus the requires passes and numerous processes are needed during isolation between the different boiling points. To be clear we may see a average 220c temperature calculation of the true boiling point of curatives as noted in the 1960s patent filed by two Israeli fellas. These were noted and explained in detail that the boiling point reached each time the components were fractioned out and tested was lowered and inherently higher during the initial pass. Do not take temperatures to heart on the head or anywhere other than the load flask. We have seen anywhere from 230-260+ required to make the initial pop. Here we will go over basic processing steps to get the curatives distillate out. When reading your distillate you can create a ultra clear extract and manipulate the bp on the second pass because the molecular density holding everything together has been lightened up dramatically. The initial fluids will hold a lot of the components you are removing with a tension that reflects the heads and distillation performance. Where the curve is seriously altered after the initial body has been removed you are now able to dial in less temperatures, up to 50c less, and use different types of pumps to create different effects and results.

Preparation for the first pass

To begin we suggest using hardware to duplicate this process. Without using the exactly hardware your protocol processing steps will be all over the place. Replicating a using components designed for proper operation of these processes is very important. Using cheap chemglass, or lab boy glassware will always serve the user with issues. Short paths, crappy glass, leaky glass, etc and so forth. In our testing we have achieved the PERFECT and absolutely precise design of where the molecular distillation of curatives is to reside in the SPD-1 Legacy head. The first and only curatives head to ever be released, specifically tuned for our environment when distilling.

It is very important to notice the distances, and the shape changes. As there were mathematically calculated to reflect the “earth based distillation”, the the volatile compounds distilled in short path heads. There ARE NO stock heads on the market made to operate in the way this distillation is designed to work. That is why we stand behind this head and guarantee repeatable results with higher purity, and greater efficiency in operation.

The protocol for the first pass of fractional distillation

The second most important items on this list is the correct mating of hardware. We use a digital mantle and offset flask to guide the vapor in the right way, and also keep your thermometer correctly positioned until the load flask empties. The same goes for out mono swap dc-3 cows which eliminate all contamination between fraction switching. We will talk about how and when to use a cold trap for this process, as well as how to work the vacuum. Do not kid yourself. If you have not done this before – and want to enter on a budget, you will be shocked at how difficult it is to operate the setup in a efficient manner and get repeatable results without the correct hardware.

curatives distillation, efficiency rates based on engineered specifications for production/purity shelf operation. fractional distillation protocol

SPD-1 technical op-spec.

  • Output: 430 grams in 30 minutes.
  • Range output based on mg content: 300-450 grams in 30 minutes.
  • Initial tail removal and temperature sequencing with vacuum: 30 minutes max.
  • Conversion and efficiency rate: 99%.
  • Total elapsed time from start to finish: 1 hour maximum.

Variable experienced time due to inaccurate temp and vacuum sequencing: 1.5 hours maximum(should always be avoided and practiced sooner)

One thing to remember is that t h c will degrade, the temperature wont be a enemy as the time dwelling at that temperature is the enemy. 240C for 2 hours is the same relative degrading rate as 260c for one hour. This is a example per volume load. This is not to be quoted. It is to explain the difference and those times of degraded rates of the components we want to remove are actually highly variable.

This information is a guide to prevent you from dwelling your extract too long. The concept of curatives distillations to retain yields and quality and high potency numbers is solely based on how fast the t h c main body can be removed once the main body pops. And long term dwelling or temperatures that sit too long between fraction separations tend to cause contamination.

Now we begin the process of sequencing the vacuum and temperature to ensure we push out any contamination and unwanted odors or components from the load before collecting the main body. Myself as a individual who was learning, the fist two times were so bad I vomited and almost gave up. Within the tenth time i was so good at isolating this odor and removing it, my students were shocked to barely smell it. We had to show them the flask itself to learn what that smell was or else they would not be able to identify it – and prevent it. But i will never comment on anyone inability to do so as it is very tricky and requires a fine method of operation where no mistakes are made during the sequence.

The initial sequence is followed in a “two steps forward, one step back” tech. Note with temps and during main body tuning this is the rule of thumb. For the temperature we will set it to a desired number and far before that number is reached we will increase the temp. Do not ever set your mantle to say 240c and walk away. The digital systems now a days may keep temp, but do not sequence it. This sequence is based on a 600-800 watt mantle for 2l, and will suffice for a 5l with a “double rate” by volume increase in wattage. Example, a 1000watt 2l litter mantle needs a further rated sequence with a enlarged bandwidth increased before vacuum can follow along with temperatures. Int his case we are talking about a standard medium wattage high temp board pid control. Our 2l and 5l mantles all follow the doubling rule when we have them made to spec. This also matters how accurate and responsible your thermoprobe is. For sake of education and operational guidance this is revolving around our style of mantles. We have yet to find a affordable version by any other company that has the correct ramp speeds added, and thus not allowing a digital unit the ability to screw up the process of sequencing the temperatures and vacuum depth so this is to be done by hand, an the results speak for themselves.

MANTLE                 TRAP                  HEAD CONDENSER

60c                            ***                                0c

100c                          ***                                 –

140c                          ***                                 –

180c                          **                                   –

220c                          *                                    –

230c                                                             40c

240c                                                             40c

250/260c                                                      40c – (up to 50c avoid if can)

This process should be observed that when we set it to 60c, and the temp is 10c away from 60 we set it to 100c. When the temp is 20c away from 100, we go to 140c, and we follow that 20c chase rule until we hit 220c, and step 10c one after the other within 1-2c away from orig target temperature. 250/260c is relative because depending on the molecular density, and the load flask ability to release desired boiling points this can vary. We have seen more efficient reactions with 250 with some material, vs 260c as a common go to temp for nearly all the material we have handled.




This is the sequence of use with a cold trap. The actual numbers and temps here vary considerably. Cold trap is to be used during the initial solvent removal stage and along with any other volatile compounds that are being removed. However when the vacuum in the load flask is depleted because the cold trap is slowly releasing atmosphere internally from boil off it is wise to disconnect the cold trap. Slowly dump the vacuum in the system and quickly swap the threaded ends from the top of the trap to the cow and restart the process.

This is a guide and not a exactly sequence as the sequence itself changes with every material you run slightly.

The vacuum sequence will be as follows:

MANTLE                  VACUUM % RPM

60c                               30%

100c                             30%

140c                             50-75%

180c                             50-75%

220c                             75-100%

230c                             100%

240c                             100%

250/260c                      100%

This is very tricky, and normally only be done with a vacuum control valve and a aux valve used to pin down ultimate cfm on vac. Not ultimate vac. The easiest but hardest way to acquire this process is getting a variable frequency controller. Without on you may need to use a series of needle valves and atmosphere bleeding valves. Note all series valve hosing to be used on a displaced manifold, so if needed the link can be entirely removed from the hosing circuit and adapted to direct vacuum control with one regulator(if needed).

The process is as follows for entire fractional distillation of the main body, however note that base on vacuum performance, and user experience these numbers can be altered. This is a basis to teach you how to do this. This is basis to learn and it should be followed precisely and thus can be altered after the entire grasp and ability to control each factor has been mastered. Once you move outside of this process with hardware variances the entire process will vary dramatically but the over all operation and mechanical performance itself will be near identical. Just the process protocol itself will shift from either direction on a sliding scale.

First make sure all glassware joints are cleaned to sterile quality before assembly. Possible use of grease is needed for new users. Do not ever attempt to switch the cow or turn any glass while at vacuum. If you have a issue shut it down, and kill the heat. Yes the alcohol will continue to boil off and most likely degrade the clean joints and load them up with earl and all kinds of nasty stuff. Disassemble the unit and let cool back to room temp, both glassware and mantle itself or else it will force this vapor up and contaminate and ruin the clean joints you have. Bad joint health will lead to failure and or depletion of vacuum or even welded joints and broken glass.

Now while you initial temps are rising you will set 200rpm, and this should be enough all the way to 2/3-3/4 of the main fraction body you are removing. Then you may raise the rpm to 400, and then to the end 600. this is only needed to basically splash and move the fluid up on the glass to get a more efficient boil off when the load flask is low and the vapor pressure provided is not entirely powerful enough to generate a reaction. Over head stir or wipes are relatively useless when it comes to curatives distillation as the performance curve is established with the ability to generate vapor pressure under vacuum. Treat the pill, a small pill is all is needed to create the proper spin. Do not get a crazy sized pill as it is not needed and can dis-balance and throw itself around causing the glass to break. You are better off using smaller stir bars to not dislodge or damage your thermometer probe. This is why our setups come with stainless probes to prevent glass probes from shattering as well.

Beginning the process of distillation will start with removal of solvents. The cold trap will be spitting solvent at this point, do not attempt to control the condensing rate in the head itself. Allow the 0c set temperature to actually do what it can, condense some alcohol and the rest is vapor to allow the col trap to condense the rest. If you use a variable freq controller start off at 30% and with the regulator basically breathing, by watching the fog in the cold trap you will be able to control how much of the regulator is dialed in. Too much fog coming up to the vac port – open regulator, too little happening in the cold trap – close regulator. This needs to be accomplished while also tending to the load flask reactions. It can sometimes be violent. But you do not want it to look like still fluid. You want to see it bubble and bounce a little. This means you are entering each reactory phase. If it is still and vacuum is deep, it is a indicator of a leak or a more serious issue. However do not let the reaction bump past the neck. If it does whatever went past that neck is basically garbage – you are welcome to disassemble the unit and reload it back in if you screw this up. But that takes time. And it is easier to abandon that little 50ml of fluid so to speak.

During the time it takes for all the alcohol to evaporate your vacuum levels will need to go deeper. Around the time where the alcohol looks like its gone you will not only increase the depth of vacuum but now start ramping the variable control on the vacuum pump up.

During the initial distillation of more volatile compounds you will notice that the reactionary effect depletes itself and now stuff will be boiling out of the cold trap. This is a indicator to shut down the system and switch the vacuum line from the cold trap directly to the cow. As well during this point you’ll increase the vacuum control to 100% rpm while still re-engaging the vacuum depth as needed to begin fractioning out the initial non volatile compounds.

We suggest around the time you are doing he bypass from the cold trap you will already have timed out the system to apply 20c temps on the condenser. This timing is crucial or else you will simply cause a blockage. Vacuum will die and maybe even pop the head off the load flask if pressure persists. From the moment the solvent is distilled along with volatile compounds to beyond the moment you do the cold trap bypass you are already preparing the chiller to rise to 40c. From this point on your temperature will eventually match up to 40c on the condenser and level out there by the time you hit 220-240c. This is crucial as you are not only sequencing everything in vacuum stages but temperatures and without aligning this process correctly you will immediately run into issues.

In turn, BEFORE the t h c main body hits – you will be at 40c approx half way through the initial tails where all the nasties come out. Those smelly components are everything from terpenes, to chlorophyll, plant dyes/pigmentation, waxes, fats, lipids etc… you must already be at temp at the neck condenser before, or else these thicker/harder components will load up and clog the neck.

The amount of tails is very dependent to the product you are removing. We have counted anywhere from 15-40 fractions on average will boil off far BEFORE the t h c main body starts to boil off. A indicator of this presence being the garage is that the reaction is the neck will increase, and decreases or even cease to exist. This is the boiling point that ends. When t h c or main body hits it should be the highest % of boiling compounds present. Meaning IT WILL NOT STOP until the reaction is entirely over and you have depleted the vapor pressure avail to create this process and sustain it. If you think you are at the t h c. You probably aren’t. The initial components once close to t h c look very similar. But are very NOT similar. Wait. Be patient, if you are on the main body allow it to run for a several seconds to clear the pathway and allow it to self clean. When you switch the glassware out this will prevent cross contamination and odor issues. If you think you are on the main body, and you do the switch. Then re engage the process and then the fraction dies on its own 2 minutes later. You were not on the main body. Again – the main body once it pops will not stop reacting at all until it depletes the compounds that are available for the reaction itself. This can be tricky and you have no contaminated your batch. This is why being patient matters or expect to buy lots of extra glassware to accommodate for these mistakes as cleaning and maintaining the glassware IS NOT A OPTION HERE. You will over extend the dwell times and ruin your output product. These switches must be done very very fast or else your mantle or any heating system on any distillation apparatus will over shoot temps as the evaporation creates a thermal condensing effect and self cools the hardware.

Now comes the very very tricky part. Using a series of cows, or even a tree port cow you will have to accomplish a switch. Even if it means taking off the cow and capping off the other two sides and moving it to the opposing side to isolate contamination or using our mono-cows for rapid switches and completely isolating any contamination that may persist through a system. The notion of turning your cow is a myth, dangerous practice and should never be down under vacuum or operational load. This glassware, and the necks get very very hot and even if it did not break – and the load flask broke under vacuum it will throw 450f fluid all over the place. This is not fun. Remember there is only one correct way to do these series of steps. We feel like going outside of this, not only is bad, but not worth the time to have a issue and then have to relearn it again. Once the t h c main body hit you will allow the path to clear itself. At this point break vacuum and allow to disengage the seal on the cow. Remove the cow and either replace it with a clean set of glassware, or remove it, and cap off the other two sides and move to the opposing end and reinstall it.

At not point in time should you ever be collecting the main body t h c while allowing other receiving flasks on the cow to hold the tails. This will continually contaminate the surface of the clear. As these tails do boil off as well depleting vacuum performance and they are present. As a example if u think u can smell it in the flask – it must be removed. No questions asked.

The practice of not removing these spent flasks is astounding and we see people doing it all the time on facebook and instagram and we cringe.

The whole concept here is to isolate, keep clean, and make sure you stride for the best process protocol you can get. Each run yields thousands of dollars at times. A excuse that a lab cant afford a few hundred dollars in spare glass is ridiculous. Ludicrous!

This is a very difficult part to do here. After switching the glassware. Your vac will be direct by now, long by now…. and the system will be void of all contaminated glassware/surface area and replaced clean. Vacuum will be turned on while the regulator is breathing. And the process will begin to restart. This section is to explain how to control and restart the reaction. With the slightest turn bring your load flask to a slight pop/boil, nothing dramatic. This will be spinning at 200rpm and it will seem sort of poppy. Slowly begin raising the vacuum depth. You will begin to see a “over reaction” in the boiling flask with a high boil. Avoid pulling through neck. The trick to this is two steps forward, one step back. You will continue to drive the reaction forward, and every time u move a hair forward on the regulator – you are to move half a hair backwards. This will create the alleviation rate response. There is a threshold where everything looks like it will explode. But not really. We want to go beyond that. How you say? Wont my nix just get sucked up? Yes and no. The reason behind that loaded question is, if you can pull a higher vacuum than what can boil off in a reactionary state; to resulting reaction thereupon is the loss of the “overboil reaction”. The actual process of alleviating pressure further than it can be provided will entirely “overboil-react-drop” this will pull the reaction beyond its ability to boil and the fluid will entirely drop. Think of it like warm purge muffin tech. Where the muffin rises and drops instantly after and just turns to a slab. In the same instance you will find the vacuum pressure seems bad and powerful. If you keep going it will nearly immediately look like its going up, then down, and then back off and level out. The fluid itself will flatten and just look like the spin bar is moving with small bubbles. This is the decarb effect and its loosing the C-OO, or co2 portion of the molecule. Right now the vacuum pressure and alleviation rate is so high that the gap between the head and fluid of the load flask is PURE hot boiling vapor. The reaction will now become more violent and powerful in the head. Gathering in the head and creating the distillate flow. Without crossing the threshold you will immediately lose efficiency until that point. This is the point where efficiency is created in the reaction. The only issue is, with a chemglass or short stock heads the space and gap is so small that the rejection rate is not accomplished.

Here we talk about identifying features and results of operation of mantles. The distance between the load flask and vig is the gap of vapor where pressure is derived. The vig section is designed to create a heavier condensate reaction, and as the molecules are hot and separate, but react they will reject and send back the heavier even higher boiling point compounds while the lighter ones come through and pass through the vig reaction area. There is then the effect of gravity that is void from most other systems. Also consider the purity shelf in our heads both brightens colors and increases potency and efficiency – something no other heads do. We like to think the perfect math can be done to achieve a basic reaction and result. This is backed with side by side testing of different sized heads that all operate in a non efficient manner. This is why we are adamant about making gear designed specifically for performance.

These topics we threw in here is to show you what we as lab workers look for. Without understanding those concepts it can be difficult to run a short path. There is no such thing as set it and go. You really do need to watch and understand what is happening. Understanding what is happening and how to control it will fine tune your skills exceptionally.

During the collection of the main body at the first pass you will enter a moment where the reaction is occurring, and the condensate is dripping all clear. Base your reaction on either 1/4-2/3 reactory effect in the neck. Beyond this is okay, but it is considered high production output style, with less separation power but extremely high output ability. In many cases you can tune and run a spd-1 with that high output processing capacity with outstanding colors and still be void of flavor and odors.

While you tune and get the reaction to sustain itself during this time, and only this time you will reach a “hands free point” and nothing should be touched or altered. Like we said earlier – once the main body hits, the pressure from vapor boiling off will be so high and intense that you wont be touching anything and it will just pour out. That is how you know what fraction you are onto of. If it dies, then you have 1% of the body in those crap distillations, if it sustains then you have 99+% of the body during the distillation. Again you can tell with how violent and fast the reaction occurs. This is the main portion you are removing.

In the near minutes after the reaction subsides you can crank up the pill to 600rpm and splash some more fluids on the glass sides. But the reaction will eventually die. This is the indicator your main body is complete and you need to shut the system down and disregard the rest. The defining point is when the bright clear reaction in the neck turns darker orange. This is the last of the c b d, cbg, cbn etc components. It will also coat a orange tint to all of the glass. This is the indicator you can switch it out sooner and collect this darker stuff in another flask. Or you can continue until the reaction dies. We prefer to take it till the reaction dies. This way we get a fully activated and wide profile distillate that is nearly 100% bio available.

We will return with more information shortly, we are working in office, brew on this we will complete the process….jbv

7/11/2016 updates hardware package for success. Updated procedures:

First off we love to say in the past times we thought we had it down. Nah. Now we have shit way down. The goal was to use the known techniques, and processes to gather a control. And learn how to expand. We can outfit labs now and produce 40lbs of clear in a day in no sweat. So lets get you on the path to success. This is the list of the most common selling package and what it entails. Then we will get into what we have been doing different for the installations. And how we are controlling it.

  • Summit Research 20L Max Rotovap
  • Polyscience chiller, either a 1.5HP chiller or 3HP chiller. (we no longer sell other brands due to common issues we want to avoid with customer purchases :-))
  • 4 head diaphragm vacuum pump, with a SVC-1 vacuum control or a 12C Vario which is an 8 head diaphragm pump with a built in controller. These are the best options for rotos.
  • Summit exclusive vfd Edwards 30.
  • 2L SPD-1 Legacy short path distillation kit.
  • Summit Swagelok distillation solution.
  • The original Sondergut Silikate Pulver.
  • Summits carbon solution.

This is the kit to success for colors, and reduced fractions to obtain the best quality possible.

The Max Rotovap is the best option over your more basic options on the market, they recover twice as fast with proper controls. Also the uber benefit is less time needed. You can use a larger chiller and RIP it through much faster than just 2x the speed. Its a durable unit!

The 4C, SVC-1 and 1.5HP configuration is setup for mild to semi hot temps at full tilt. The duty cycle will not be affected…only how much heat the chiller can take off (this means cranking it will still get fast speeds but the chiller wont be at 0c anymore, it will ride between 3-8c while still functioning aggressively).

The next option upgrade is as follows and is the only way to remove enough heat from the condenser and even allow the internal heating program to dump enough heat to keep up with the larger vacuum pump : 3hp chiller 13-14k -6c  (more than enough power w/ 2-4 week lead time – built to order atm). 12c vario – 13.5k this is a specialized high performance pump setup and it connects to the roto with a bellow and has a variable speed controller. (Usually in stock – this is the most advanced vacuum pump ever made hence the price)

The polyscience chillers are made in USA and made to order unless you pickup from our store stock. We have had ZERO issues with these unlike most any temperamental chillers on the market. But hey, its not a sales pitch. We just don’t want to see you again over a chiller in the future.

We NO LONGER endorse Cole Palmer vacuum regulators. They aren’t the best, but after over a year of being loyal we say as a entry method it works. As a solution for future it doesn’t work.

We now sell a three valve manifold which allows nitrogen flow control, distillation control, and ultimate vacuum throttling. This is the best valve setup we’ve seen to date. And our part number from swagelock mimics the package we provide in quality. These will come sealed and they will give u endless use without any rebuilding needed. However it can be rebuilt, washed, re assembled and you just need seals. So this new swagelok package is truly a step up in the game of distillation control.

Here’s the kicker. We get an exclusive build out and customization package for Edwards 30 pumps. This will really let you control the distillation parameters.

We take our rebuilt pumps and we scrap the motor since it will not suffice this kind of abuse. We then order a brand new USA multi freq motor and have the shaft shaved down, shortened and notched to fit the coupler on the Edwards 30 pump. This is not common and is 100% custom. We will include a TOP OF THE LINE SPARED NO COST vfd digital controller in the package. This is a no brainer. Get it, and enter the future of vacuum distillation control.

So all in all we have a detailed list here, other than lab stands and hoses, plus some basic hardware you will be ready to dump out lbs upon lbs of clear in a day with a basic 2l setup.

fractional distillation

so. what have we changed? Not much, we still run machines like champs but we ran into a few issues, so from here on out this is a basic informal bench of what we follow.

  • Winterize.
  • Repeat until epic no coagulation.
  • Carbon scrub – with matrix mixed.
  • Silicate scrub the solution from remainder dusts and final polish.
  • Nothing, i repeat nothing gets touched without being fully dewaxed and scrubbed to the max.
  • Roto down.
  • Decarb rapid to 150c to degreen the initial stage.
  • Put in load flask warm, not super hot.

Go for it.

If you think we left something out, and want anything added or talked about here please email and well be happy to add relevant into.  -JBV