Wiped Film Distillation & Evaporation

Wiped Film Still Stainless Steel Conversion Kits

Posted on April 8, 2025

Wiped Film Still Stainless Steel Conversion Kits

Pope Scientific offers standard 2”, 4” and 6” Wiped-Film Still systems fabricated with 316L stainless steel in addition to glass. These Wiped-Film Stills not only offer a more robust construction, but also allow you to process at greater feed-rates. Stainless-steel has a greater thermal conductivity coefficient than borosilicate glass. This provides more than double the processing capacity for a still of the same size. In addition, 4” and 6” stainless steel internal condensers have high surface area due to a multiple vertical tube design, allowing yet additional throughput

For customers with existing all-glass stills, Pope’s 316L SS conversion kits, are available. These consist of a stainless-steel body and internal condenser plus all the necessary adapters and clamps to re-attach the existing glass components. Pope recommends that operators be experienced with the Wiped-Film Stills in glass, with their greater process visibility, before switching over to stainless steel.

Pope still systems in all sizes are also available in totally stainless-steel fabrication for continuous, industrial duty. These are typically skid-mounted turnkey systems, and can be of multi-stage, once through design and with optional advanced PLC control. Contact us to discuss your specific application requirements.

wiped film still stainless steel conversion kits

Pope 6″ Wiped-Film Still with Stainless Steel

wiped film still stainless steel conversion kits

Pope 6″ Wiped-Film Still with Glass

 

Pope Scientific Featured in Chemical Today Magazine

Posted on March 7, 2025

Pope Scientific’s Dean Segal Featured in Chemical Today Magazine

Chemical Today Magazine Interview

We’re excited to announce that Dean Segal, VP of Sales & Marketing at Pope Scientific, was recently interviewed by Chemical Today Magazine. In the interview, Dean discusses the latest advancements in distillation technology, sustainability efforts, and strategies for overcoming industry challenges in chemical processing.

Key topics include Pope’s Wiped Film and Hybrid Distillation Systems, which help processors in lubricants, fuels, and petrochemicals achieve high-purity results while minimizing thermal degradation. Dean also highlights AI-driven process optimization, sustainable refining methods, and solutions for scaling production efficiently.

A featured case study showcases how Pope’s distillation technology helped an aerospace lubricant manufacturer eliminate degradation and achieve superior purity, leading to a successful full-scale production system.

📖 Read the full interview here.  View the full magazine here.

Want to learn more? Contact us today!

Scale Up Your Oil Purification with Pilot-Scale Wiped-Film Molecular Stills

Posted on February 26, 2025

Scale Up Your Oil Purification with Pilot-Scale Wiped-Film Molecular Stills

As demand grows for new formulations and increased purities of oils and fats, bridging the gap between lab research and industrial production has become more critical than ever. Pilot-scale molecular stills are the perfect solution—a logical bridge between the lab bench and the production floor. They allow for creating drums of customer samples, meeting material demands, and serving as accurate testing and scale-up tools for large-scale commercialization projects. Whether you’re refining edible and essential oils, bio-based materials, or specialty extract distillates, these molecular short-path distillation systems are designed to meet your unique purification needs, from customer validation to compliance with cGMP, all while enabling the development of new and improved products.

Why Choose Molecular Stills for Purifying Oils and Fats?

Pope 6" Stainless Steel XP Wiped Film Molecular Still Pilot Plant System

Pope 6″ Stainless Steel XP Wiped Film Molecular Still Pilot Plant System

Molecular stills excel at purifying oils and fats due to their ability to separate heat-sensitive, high-boiling-point compounds without degradation. This is achieved through optimized designs featuring high-vacuum continuous operation, which decreases boiling temperatures, and efficiently wiped evaporation surfaces, which limit heat exposure to mere seconds. The results include greater yield and purity, as well as product separations and creations not possible by any other means. Importantly, this continuous-mode technology does not require chemical additives, preserving the integrity of natural products. This is particularly important for applications such as:

  • Edible Oils: Removing contaminants and improving yield, flavor, and shelf life.
  • Essential Oils and Fragrances: Preserving aromatic compounds while ensuring purity.
  • Bio-Based Materials and Specialty Chemicals: Achieving high-purity end products for advanced applications.

Real-World Impact: Purifying Oils with Pope Molecular Stills

At Pope Scientific, we’ve collaborated with companies worldwide in the oils and fats industries to optimize their purification processes. For example, a specialty oil producer sought to remove undesirable compounds to meet FDA compliance while preserving the delicate flavor profile of their products. By utilizing Pope’s expert testing and tolling services and investing in a Pope pilot-scale molecular still system, they achieved:

  • Higher purity, yield, and appearance with no thermal degradation or flavor shift.
  • Scalability for larger production runs, including reduced energy consumption and material costs.
  • Market expansion with new premium-grade and customized flavor products.

Stepping Beyond Molecular Stills with Pope Hybrid Still System Technology

4” Stainless Steel Hybrid Wiped-Film Distillation

Multi-column design allowing for mid-column feed. Discreet controls and manual operation.

For applications involving compounds with multiple components close in boiling point, a greater degree of separation of heat-sensitive materials is required than molecular distillation alone can provide. For these situations, Pope has developed Hybrid Stills, combining the gentle wiped-film evaporation technique with the high-resolution separation power of multi-theoretical-plate fractional columns. These systems deliver sharper separation cuts for feed materials. Examples include:

  • Customizing flavor variations in citrus, mint, and other oils.
  • Fine separation of C-14, C-16, and C-18 peaks in FFA and FAME for optimal yield and purity.
  • Concentrating DHA, EPA, and other Omega-3 esters from fish or fermented oils.

Prove Your Concept with In-House Lab Trials

  • Proof-of-concept validation with your material, plus determination of the optimal still system design.
  • A pathway to outsourcing through Pope’s toll processing services before your equipment delivery.
  • Actionable knowledge for experimenting, piloting, and operating your own equipment

Why Choose Pope Scientific?

With over 50 years of experience, Pope Scientific has been a trusted partner for companies looking to elevate their distillation processes. Our solutions for purifying oils and fats cater to industries including foods, flavors, fragrances, vitamins, supplements, cannabinoids, terpenes, waxes, botanical extracts, surfactants, monoglycerides, triglycerides, cosmetics, biofuels, and many other oils and derivatives. Our equipment and services offer:

  • Customizable Solutions: Tailored to meet your specific needs.
  • Proven Performance: Trusted by leading companies worldwide and validated for cGMP processing.
  • Exceptional Support: From process development to installation and beyond.

Take Your Process to the Next Level
Ready to scale up your oil purification process? Discover how pilot-scale wiped-film stills from Pope Scientific can help you achieve your goals. Contact us today to schedule an in-house lab trial and take the first step toward production success!

Understanding Short-Path, Fractional and Pope’s Wiped-Film Molecular Stills

Posted on April 7, 2022

Understanding Short-Path, Fractional and Pope’s Wiped-Film Molecular Stills

Oftentimes when people are considering distillation equipment for processing hemp and cannabis, there seems to be a lot of confusion and misuse of terminology with short-path stills and Pope’s wiped-film molecular stills.  We have explored some of the key points below.  

What is Molecular Distillation?  

Molecular distillation and short-path distillation are the same things. These both imply the use of high vacuum and a condensing surface in close proximity to a heated evaporation surface. For many applications such as cannabinoids and as well as other compounds with greater molecular weight and boiling points, if the distance is not close enough, the equipment will not work well, if at all. 

What does short-path mean? 

We discovered some people perceive the term “short-path” to imply a basic glassware setup involving a basic boiling flask with a neck leading to a condenser and a

Fractional distillation diagram

Image source: http://www.chemhelper.com/distillation.html

receiver flask(s), or else a similar variation called a KIugelrohr. These are oftentimes also referred to as pot stills, (pot as in a vessel, not in the cannabis sense), and are all considered batch mode apparatus. However, these only refer to one type (the simplest type) of short-path or molecular stills. There are other forms of short-path

setups including Pope’s continuous mode Wiped-Film Molecular Still (WFMS). 

Is a fractional still the same thing as a short-path still? 

Fractional stills are not short-path stills. Fractional distillation equipment implies the utilization of a vertical packed column providing multiple equilibrium stages or “theoretical plates”, requiring the condenser to be further away from the boiling container (reboiler) and reached only after the obstacle of the packed column. While this can be used to increase the purity of a distillate, it is instead a problem for heat-sensitive materials such as cannabinoids. Though Pope does offer fractional distillation equipment, the single theoretical plate of molecular stills is sufficient for most cannabinoid work and offers the least product degradation.

 

What are the advantages of a wiped-film still compared to a boiling flask short path setup? 

Now that we have a good understanding of short path, we want to dive into the advantages of Pope’s WFMS over a basic boiling flask type molecular short path still.

2” Standard Glass Wiped Film Still

Complete Molecular Still Package System with electric band heating (bands removed), external condenser, all utilities, plus optional feed pump.

One key advantage is that the Pope WFMS is a continuous mode, rather than batch mode still. This means that with larger or special flasks, or with liquid pumps, they can operate for extended periods of time with any quantity of feed material and with the same consistent product composition over time. The Pope WFMS is also scalable, such that when much larger quantities of material needs to be processed, larger versions of the same type of equipment can be utilized to accommodate the greater throughputs required. Batch mode stills such as the boiling flask short path still can be scaled but lose efficiencies due to heat and mass transfer limitations resulting in extremely long operation times and loss of product to degradation. 

In addition to scalability and continuous mode, another advantage is the Pope WFMS offers much less thermal degradation and greater product purity and yield. This is for two reasons. One, there is a very short residence exposure time to a heated surface – only a matter of seconds, compared to many hours in a boiling flask molecular still. And two, the WFMS has a highly efficient dynamic rotating wiped film action providing turbulent moving thin-film mixing compared to the limited, less dynamic liquid/vapor interface of a simple boiling flask apparatus. 

Have more questions on terminology or Pope’s Wiped-Film Molecular stills?  We are here to help answer your questions. Contact us to learn more or speak with a Pope team member.  

Introducing the New Pope ProPass-600 Canna Still

Posted on October 3, 2021

Introducing the New Pope ProPass-600 Canna Still

Providing the highest performance – greatest throughput / price ratio

Recognized for decades for molecular distillation excellence, Pope Scientific proudly presents the ProPass 600 series of Canna Stills. This single-stage wiped-film distillation system contains the core essentials for reliable, round-the-clock operation. All 316L stainless steel construction with no glass except for armored sight glasses provides durability and high heat transfer rates for maximum efficiency and throughput.

The ProPass 600 has been developed from Pope’s 7+ years of experience in the cannabinoid distillation industry, backed by over 45 total years of wiped-film experience. This design includes new high-performance gear pumps, an oversized vacuum pump, a compact, heavy-duty frame, and more. The result is an industrial machine ready to take on a wide range of different qualities of extracts and provide high purity and yield distillate product. And as always, backed by Pope’s unmatched customer service and technical guidance after the sale!

REQUEST A QUOTE

Pope ProPass 600 Canna Still

The system comes ready to process the two typical passes – terpenes removal and cannabinoid distillation. Additional passes are also possible. For large feed lots, two ProPass modules linked together are highly recommended for optimization of daily throughput and minimization of maintenance and cleaning/drying time between passes. Linking together more units is also possible at any time.


The Pope ProPass At A Glance:

  • Developed to provide the greatest reliable throughput per dollar possible!

  • Choice of an electric band or hot oil jacket heating.

  • An industrial duty no-frills, robust and efficient 6” Wiped Film cannabinoid still.

  • Designed as an all 316L stainless steel system, not a modification of a glass standard still system.

  • Features a single-stage system capable of performing the typical two types of passes for cannabinoid distillation or for other special one-pass applications.

  • Modularly designed for expansion of production needs, and easy linking of extra stages in a series if required – no need to purchase “all at once.”

  • Includes the basics for what is necessary to start continuous processing right out of the crate, with the option to upgrade components based on a customer’s preferences and budget.

Key Features:

  • Up to 10 L/hr feed rate
  • Single point power distribution panel
  • New high-performance liquid and vacuum pumps
  • All wiring to NEC industrial standards
  • 316L SS used on all wetted metal parts
  • Also available in 4”, 9”, 12” and 20” ProPass sizes
  • USA designed and manufactured
  • Industrial duty and performance

Using a Mass Balance to Evaluate Your CBD Distillation Process

Posted on May 4, 2021

Using a Mass Balance to Evaluate Your CBD Distillation Process

If the average person was asked to do a mass balance on a system, they might not quite understand what is required. However, for chemical engineers and industrial process chemists this is something learned quite early in their curriculum. While it is a tool often used by chemical engineers, there is no reason why it should not be part of any processor’s toolbox.

For processes involving chemical reactions, the mass balance is written out as:

INPUT + GENERATION = OUTPUT + ACCUMULATION + CONSUMPTION

Pope Mass Balance Illustration

However, when you are just using separation equipment (such as a wiped-film molecular still for distillation), the equation gets simplified to:

INPUT = OUTPUT + ACCUMULATION

Then, by defining the boundaries of a system, it becomes possible to check where your material is going which can allow you to make better decisions and optimize your process.

Let’s assume you are running a wiped-film molecular still to create CBD distillate. The INPUT to the still will be the feed material (the crude). The OUTPUT of this separation will be terpenes, residue, and CBD distillate. The ACCUMULATION would be any residual material left in the still. There are other outputs; the ethanol collected in the cold trap and any material that is lost through the vacuum pump, however, to simplify this exercise we will lump these into the accumulation and simply define them all as material loss.

While losses to accumulation are important, wiped film stills do not have miles of process piping, so overall this should not be a major concern on the equipment. However, by adding some analytical data to the mass balance much can be learned about your operation.

high terpene full spectrum cbd extracts in pope cannabis distillation flask

Image source: Vext Science  www.vextscience.com 

Example:

Prior to distillation, you have your crude CBD extract analyzed and the lab results come back indicating the material is 65% CBD by mass. You load the feed flask on your system with 2,000 grams of the material. You perform your first distillation and remove 160 grams of terpenes. On your second pass you get 1,155 grams of distillate and 635 grams of residue. When the lab results on your distillate come back, they show 90% CBD by mass. This seems good, but a mass balance will allow you to best review this.

For a Very Simple Mass Balance, You Have:

mcrude = mterpenes + mdistillate + mresidue + mloss  (1)

Where:

mcrude = mass of crude

mterpenes = mass of terpenes collected

mdistillate = mass of distillate collected

mresidue = mass of residue collected

mloss = material lost (to accumulate, transfer, etc.)

This yields 50 grams of material that is considered lost. Which could either be escaped ethanol or material that sticks as residual in the system (a common occurrence with high viscosity fluids).

Since there is not a large amount of material that was lost, it is now time to look at the amount of CBD you have recovered, also known as your yield. First, you must determine how much CBD is present to start, using equation (2):

mCBD-C = mcrude * CCBD-C (2)

Where:

mCBD-C  = mass of CBD in crude

mcrude = mass of crude

CCBD-C = CBD Concentration in crude (mass %)

This equation shows that 1,300 grams of CBD are present in your crude. A similar equation can be used to determine the amount of CBD in your distillate:

mCBD-D = mdistillate * CCBD-D  (3)

Where:

mCBD-D = mass of CBD in distillate

CCBD-D = CBD Concentration in distillate (mass %)

Leading to a total of 1,039.5 grams of CBD in your distillate. To calculate the yield of your process you then use Equation 4:

% Yield = mCBD-D ÷ mCBD-C  (4)

The percent yield from this distillation is approximately 80%, which would be considered quite sufficient. By further calculation, you can also estimate the amount of CBD that remains in your residue. We will assume that the 50 grams of lost material were at 65% CBD content, like the crude, meaning that 32.5 g of CBD where “lost”. By Equations 5 and 6, you can assume your remaining residue contains 228 grams of CBD or is 36% CBD (mass %):

mCBD-R = mCBD-C – mCBD-D – mCBD-L  (5)

Where:

mCBD-R = mass of CBD in residue

mCBD-L = mass of CBD lost

CCBD–R = mCBD-R ÷ mresidue (6)

Where:

CCBD–R = CBD concentration in residue (mass %)

A great amount of processing in the cannabis industry is performed without much attention to mass balancing and utilizing before/after analyses between process steps.  In many of these cases, the company will get by, obtaining adequate purities and (often unknown) yields.  A somewhat careful operator will often be able to “get the job done”.  However, consistent utilization of the principles of mass balancing, together with obtaining and studying analyses of every batch and run will allow an OK  operator to become an excellent operator.  This person will be able to plan parameters as well as strategies for each run, resulting in optimal purity and yield, leading to lower costs, better product quality, at better pricing, all eventually leading to greater profit for their company than their competitors.

How Volatiles can Affect your Distillation Process

Posted on August 19, 2020

How Volatiles can Affect your Distillation Process

By Ben Kultgen, Process and Sales Engineer, Pope Scientific

 

In this video Ben, process and sales engineer with Pope Scientific, gives an overview of how volatile materials can affect your distillation process, and how you can identify them.

If you have run wiped-film equipment before, you likely have run into vacuum issues at least once in your career. Weak vacuum can often be caused by a leak in your system, which is normally readily found, but can be sometimes frustrating to fix. (If you do need help on your Pope system, we have a team of technical resources who can help you out with this.) However, if your system is vacuum tight and the pressure increases dramatically above the desired range when feeding material to the still – what might be the issue? The cause is likely the presence of volatiles in your feed material.

 

What is Actually Happening:

Specifically, when discussing the processing of Cannabinoid extract, you are often conducting two passes to yield your high purity distillate. The first pass focuses on taking out terpenes and the second pass focuses on bringing the cannabinoid distillate away from the heavy waxes, chlorophyll, and sugars.

When you have volatile materials such as ethanol or dissolved gasses in your feed, they take up the vapor space on your first pass and weaken the vacuum, preventing all of the terpenes from being distilled, and these will be in the feed for the second pass.

Even if you leave a small amount of terpenes in your material for the second pass, you likely will not get as high of a distillate yield as you would have had the terpenes been properly removed. This directly impacts your bottom line.

Without proper devolatilization you may also negatively impact the quality of your distillate. Often when customers find streaks occurring in their distillate it is due to flashing. When you have two materials with much different boiling points, you may see flashing if the mixed material is exposed to too much heat or vacuum. A practical example of flashing is when you put water into a frying pan with hot oil. When the water is introduced, it immediately vaporizes. When it vaporizes it not only flashes the water but carries oil along with it. The same thing will happen with cannabinoid distillation when there is either dissolved gases, ethanol, or light terpenes present, and you operate at cannabinoid distillation conditions. When the light materials flash, they will pull undesired materials like chlorophyll and waxes with.

How Users try to Compensate:

Often when vacuum issues arise due to the presence of volatile materials, customer attempt to compensate in several ways by attempting the following: Running at higher temps, feeding at very slow flow rates, or trying to bully the vacuum levels down by purchasing larger and more complex vacuum pumps.

In the real world this can sometimes help, but it is not the ideal way to process. Whenever there are materials present with a boiling point difference of around 30 C or greater, the solutions that should be considered include multiple (more than two) passes, and/or prior removal of solvent to less than 0.1%. You can consult with Pope on the various methods that can be utilized to accomplish this prior to the first distribution pass.

Hopefully, this introduction to the impact of volatile materials on your process has been helpful. If you have further questions, please contact Pope Scientific to learn more about our wiped-film molecular distillation equipment and processes. Stay tuned, we have more helpful videos to come.

4 Questions on Distillation: Effectively remove volatiles and solvents

Posted on August 11, 2020

4 Questions on Distillation: Effectively remove volatiles and solvents

 

In the latest issue of Cannabis Business Times, Dean Segal, vice president of sales and marketing for Pope Scientific, explains why it’s important and how to effectively remove volatiles and solvents prior to, and early in the distillation process to improve yield and quality.

1. Why does removing volatiles before the first distillation pass matter so much?

The goal of the first distillation pass is to remove as many of the terpenes as possible. If these are removed well in pass 1, it will allow for a higher performance during pass 2, with less flashing and greater vacuum, throughput, purity, yield and clarity. However, if the feed to pass 1 also contains leftover solvent—typically ethanol—it weakens the overall operating vacuum, (no matter the type of vacuum pumps or how large they are), leading to less terpene removal. This has a spillover effect because pass 2 is burdened with more terpenes in the feed, diminishing the above-mentioned performance and results of this pass. It’s best to have much less than 0.5% solvent in the pass 1 feed.

2. But if decarboxylation is performed just before distilling, doesn’t that take care of the issue?

Many believe if decarboxylation is performed just prior to distillation, the typical temperature (approximately 130°C) of this intermediate step will drive off all remaining ethanol from the evaporation process following winterization. However, ethanol, though it boils at 78°C in its pure form, also has binding forces with materials such as cannabinoids, which make it harder to drive off. Often, more remains than might be expected.

3. So, what can be done to improve solvent removal?

If a rotary evaporator (rotovap) is used for evaporating at 60°C with a typical rotovap vacuum pump, or if a falling film still was used with a single pass, residual ethanol can remain at 3% to 8%, and decarbing may still result in 1% to 3% ethanol in the pass 1 feed, which is too much. If rotovaping, increase the temperature to at least 90°C for the final hour. If using falling film, it needs further evaporation. Another approach is to plan a three-pass distillation: solvent pass, terpene pass and cannabinoid pass. (A fourth pass is sometimes performed on distillate to increase purity or on residue as a “second squeeze” to increase yield.)

4. Over periods of days or weeks, distillation vacuum levels seem to gradually become weaker. Why?

The most common cause concerns the Gas Ballast Valve (GBV). Nearly all cannabinoid stills utilize two-stage rotary vane vacuum pumps, which have a GBV, but many operators don’t know much about them. The issue: Some portion of light components, such as solvents, can typically get past the cold trap. They then dissolve into the pump oil, especially in the first distillation pass, and with a large percentage in the feed (>1%), and/or the vacuum level is too strong for conditions. The oil’s total vapor pressure increases as a result, weakening the vacuum. But if the GBV is opened, a small stream of air enters the pump and sweeps out the dissolved solvents, allowing greater vacuum restoration and without having to change the oil. The GBV should be opened after each pass and at the end of every day for at least 30 minutes, then closed again, while the pump is running deadheaded (inlet closed). (Note that if a diffusion or turbo pump is part of the vacuum system, it will not be a substitute for using the GBV properly).

The Basics of Molecular Distillation

Posted on July 15, 2020

The Basics of Molecular Distillation

Article written by Brian Beckley for www.marijuanaventure.com

Although distillation often gets lumped in with extraction, it’s actually the step after extraction, a process that refines the raw oil, removes impurities, waxes and other undesirable elements, like chlorophyll. It turns the extract from the viscous material often used for dabs into a clearer, flavorless, high-potency oil for use in cartridges, tinctures and edibles.

The process also decarboxylates the material, changing the THCA found in the plant into what is generally referred to as “active” THC, and raising the percentage of THC or CBD to levels above 90%.

“The color and the quality of the oil is better,” says Chris Barone, chief science officer at Clear Cannabis. “Purity, potency, color, odor — all that stuff — is brought up to a higher level.”

pope scientific wiped film distillation system

An Old Process

Distillation itself is an old process, one used in many industries, but most notably for making alcohol. Traditional short-path distillation, like that of an old moonshine still, uses a boiling flask to heat the material so it evaporates and is caught on a condenser above. The mash is heated in the flask and the alcohol boils off first. It begins to cool when it hits the condenser and then drips into a collection vessel, leaving the water and other substances behind.

“In that case, you’re driving ethanol off,” explains Dean Segal, vice president of sales and marketing for Pope Scientific.

While this style of distillation was used in the early days of the cannabis industry, boiling the materials for hours at a time degrades the very cannabinoids that the process seeks to distill, resulting in less purity and less yield.

“This problem goes way back to the ’30s and ’40s, when people were starting to distill vitamins and pharmaceuticals,” Segal says.

The solution was lowering the pressure in the chamber.

“Molecular distillation, from a chemistry perspective, is a physical process that relies on heating up the liquid or the resin to its boiling point and separating the constituents of that mixture based on boiling point,” Barone says. “Specifically, molecular distillation is doing it at a substantially reduced pressure.”

The idea is to use a high vacuum to help increase the space between molecules so that they can be boiled and separated at a lower temperature than usual, ensuring a better final product.

“This problem goes way back to the ’30s and ’40s, when people were starting to distill vitamins and pharmaceuticals,” Segal says.

The solution was lowering the pressure in the chamber.

“Molecular distillation, from a chemistry perspective, is a physical process that relies on heating up the liquid or the resin to its boiling point and separating the constituents of that mixture based on boiling point,” Barone says. “Specifically, molecular distillation is doing it at a substantially reduced pressure.”


Read the entire article >>

Stainless Steel vs. Borosilicate Glass Wiped-Film Stills

Posted on April 9, 2020

pope stainless steel wiped film still, stainless steel vs. borosilicate glass wiped film stills

Pope Stainless Steel Wiped-Film Still

Stainless Steel vs. Borosilicate Glass Wiped-Film Stills

Pope Scientific manufactures Wiped Film Stills in both 316L stainless steel and borosilicate glass. When selecting a still system for purchase, materials of construction matter just as much as size and other features. Both have their benefits, but how do you know which one is right for you?

pope glass wiped film still, stainless steel vs. borosilicate glass wiped film stills

Pope Glass Wiped-Film Still

Borosilicate glass has been utilized and trusted in laboratories the world over. At Pope, our glass components are annealed to over 1100F and can be relied upon for all your daily processing needs. Every chemist likes to be able to observe what is going on and glass allows looking into the process and making parameter changes as needed. Every chemist also knows that glass can break when mistakes are made.

Pope Scientific 316L stainless steel Wiped-Film Stills don’t break and not only have more robust construction but also allow faster distillation processing. Stainless steel has a greater heat transfer rate than glass, resulting in more than double the processing throughput than its glass Wiped Film Still cousin. We do recommend gaining experience on a greater visibility glass still before switching over to stainless steel where observation is limited to material entering and leaving the still body. We offer stainless steel conversion kits with adapters to the peripheral components as well as turnkey 100% stainless steel systems with sight glasses for full process view.

Ask the Experts: 5 Questions on Wiped Film Distillation

Posted on March 5, 2020

Ask the Experts: 5 Questions on Wiped Film Distillation


Wiped film distillation is often carried out using strict set of methods and parameters from internal Standard Operating Procedures, but incoming extract material composition is not fixed; it changes depending on various factors, so do product goals. Dean Segal, vice president of sales and marketing for Pope Scientific, shares distillation approaches and strategies for adapting to such changes for optimization of product quality, yield and profit.

  1. Do Wiped Film Molecular Stills Operate Similarly to Boiling Flask “Short Path” Stills?

No, boiling flask stills are batch-mode apparatuses where compositions change incrementally the entire run. Wiped film molecular distillation is a continuous mode operation, thus the feed, distillate and residue compositions remain constant for the entire run. Feed material, kept flowing at a fixed feed rate, enters a high vacuum heated boiling zone for a short residence time, where some portion of it is evaporated away and condensed. Thus, the feed is split into two streams, distillate and residue, both being collected and/or pumped away. Three principal operating parameters— feed rate, temperature and vacuum level— determine how much is collected as distillate and how much is collected as residue, sometimes referred to as the “split” or “Mass Balance” (MB).

  1. Should Molecular Stills be Run the Same Way Each Time?

Incoming feed material changes in quality and composition, plus product goals can change as well. Thus, for optimal results, it’s better to modify parameters rather than keep them fixed for every run. A rule of thumb is to shoot for splitting the feed into something close to the total cannabinoid percentage. For example, if a new extract lot comes in at 60-percent total cannabinoid, aim for a MB of roughly 60:40, not 85:15.

 

three stage six inch cannabinoid distillation machine

Pope Turnkey, 3-Stage, PLC Controlled, Pharmaceutical-grade, Cannabinoid Distillation System

 

  1. How is Distillation Optimized to Accommodate Product Goals?

One approach, (A), is quality over yield; the other, (B), is yield over quality. In approach A, one may adjust the temperature to a MB to correspond to a bit under the percent of cannabinoid, resulting in a clear yellow distillate of good quality. There may be a nominal amount of cannabinoid remaining in the residue that can be combined later with other residues from similar runs, and later, this material can be re-distilled to recover a “second squeeze” of cannabinoid for less critical product use. In approach B, a “deeper” cut is made, with MB somewhat greater than the percent cannabinoid to ensure most of the available cannabinoid is removed. If the goal includes having at least some premium-grade product, the distillate, instead of residue, may be re-distilled to obtain product upwards of 90% cannabinoid, and the residue, depending on its analysis, may be utilized in a secondary product line, particularly when clarity and lightness is not essential, e.g., chocolate edibles.

  1. Can Different Strategies be Incorporated into the Design of a Production System?

Yes, this is accomplished by having more than two stages in the system. If there are three stages, the third can be used either for re-distilling the residue (increasing yield) or else re-distilling the distillate (increasing purity). Alternatively, the first stage could be used for stripping out excessive (>3%) solvents, the second for collection of any remaining solvent and heavier terpenes, and the third for cannabinoid distillation. Having four stages makes it possible to run two, two-stage distillations in parallel, doubling the throughput of the still system. Great flexibility is possible with such multistage systems.

  1. Are Terpenes Lost in a Molecular Distillation System?

Often, most terpenes are lost prior to the distillation step. If they are still present and in usable condition, they can be captured for reuse such as adding back to final distillate product via incorporation of an external condenser—a component, which is one of the features of Pope Cannabis Distillation stills.

Originally published in Cannabis Business Times

Pope On Stage at CannaTech Tel Aviv 2019

Posted on November 19, 2019

Pope On Stage at CannaTech Tel Aviv 2019

Pope Cannabis Presentation - Dean Segal

“Distillation of Cannabis Extracts” was the seminar topic as Pope Scientific expert detailed the chemical processing behind obtaining high purity cannabinoids and recovering terpenes

Dean Segal, Vice President of Sales & Marketing who holds B.S. degrees in both Chemical Engineering and Biochemistry, was on the agenda at CannaTech Tel Aviv—a next-level medical cannabis conference bringing together industry influencers and thought leaders to discover, connect and accelerate medical cannabis innovation.

Part of Segal’s presentation highlighted the reasons to distill crude extract, which included:

  • Increased purity of cannabinoids [Typical example being 65% in trim going to 85-90%]
  • Removal of heavies, chlorophyll, larger waxes, salts, sugars, higher MW pesticides, etc.
  • Product becomes clear light yellow, from dark opaque brown
  • If product is to be used as vape, better to leave out heavies and solids
  • If product is to be isolated [chromatography, crystallization, etc.], results in greater purity and much greater yield
  • Improvements are gained without introduction of solvents, etc.

Segal also worked the trade show floor representing Pope Scientific at the Rhenium booth. A sponsor of the event, Rhenium is one of Israel’s leading suppliers of laboratory, research and diagnostic equipment; working with top-level manufacturers from around the world like Pope to import solution-driven  equipment.