If you’ve ever worked in a lab, kitchen, or even a garage, you’ve probably used effective laboratory equipment like funnel at some point. Funnels are simple tools, but not all funnels are the same. Two types that are often confused are the filter funnel and the separatory funnel.
At first glance, both are used to move or separate liquids, but they are designed for very different purposes. If you’ve ever wondered, “Which one should I use and why?”, this blog is for you.
What is a Filter Funnel?
A filter funnel glass is probably what most people think of when they hear the word “funnel.” It’s a cone-shaped tool that you use to pour liquid into another container without spilling. What makes it a filter funnel is that you can place a piece of filter paper inside it.
When you pour liquid through the funnel, the filter paper traps solids, dirt, or particles, and lets the clean liquid pass through.
When do you use a filter funnel?
- Removing dirt or particles from a liquid.
- Making coffee using paper filters (yes, that’s basically a filter funnel in action!).
- Filtering solutions in a lab to get rid of unwanted solids.
Advantages of a filter funnel:
- Easy to use.
- Affordable.
- Works well for both home and lab use.
- No complicated setup needed.
In short, a filter funnel is your go-to tool when you want to make a liquid cleaner by removing solids.
What is a Separatory Funnel?
A separatory funnel looks quite different. It’s usually made of glass or plastic, shaped like a teardrop, and has a stopcock (a small valve) at the bottom.
A separatory funnel is not for filtering solids from liquids. Instead, it is used to separate two liquids that do not mix, for example, oil and water. These liquids naturally form layers because they have different densities.
How does it work?
- You pour both liquids into the separatory funnel.
- You let them settle until you clearly see two layers.
- You slowly open the stopcock to let the bottom liquid flow out first, leaving the top liquid behind.
When do you use a separatory funnel?
- Separating oil from water.
- Removing a solvent from a mixture in chemistry experiments.
- Extracting one liquid ingredient from another in lab processes.
Advantages of a separatory funnel:
- Makes it easy to separate liquids without spilling.
- Saves time compared to other methods.
- Accurate and clean separation.
So, the separatory funnel is your tool when you want to separate two different liquids rather than filter out solids.
Key Differences Between a Filter Funnel and a Separatory Funnel
To make it super clear, here’s a simple comparison:
| Feature | Filter Funnel | Separatory Funnel |
| Purpose | Removes solids from a liquid | Separates two liquids that don’t mix |
| Shape | Cone-shaped | Teardrop-shaped with a valve |
| Extra Tools Needed | Filter paper | None, just the funnel |
| Best For | Cleaning up a liquid | Separating oil and water or similar liquids |
| Ease of Use | Very easy | Needs a bit of practice |
| Common Material | Plastic, glass, metal | Glass or plastic |
How to Choose the Right One for Your Work
If you’re still unsure which one you need, just ask yourself:
- Do I need to remove small solid bits from my liquid? – Use a filter funnel.
- Do I need to separate two liquids that don’t mix? – Use a separatory funnel.
For example:
- Filtering coffee, juice, or lab solutions? Filter funnel.
- Separating oil from water in a science experiment? Separatory funnel.
Tips for Using Each Funnel
For filter funnel borosilicate glass:
- Always wet the filter paper slightly so it sticks to the funnel and stays in place.
- Pour slowly to avoid overflow.
- Make sure the container below can hold all the liquid.
For Separatory Funnels:
- Make sure the stopcock is closed before adding any liquid (trust me, spills happen!).
- Hold the funnel firmly when shaking or mixing liquids inside.
- Release pressure carefully if your liquids produce gas.
Conclusion: Both filter funnels and separatory funnels are valuable, but they have different jobs – one filters solids from liquids, the other separates two liquids. Knowing the difference helps you work faster and cleaner. For quality funnels and other lab tools, trust Livingstone International – laboratory equipment suppliers. We offer durable products, great service, and fast delivery. Whether for small tasks or bulk orders, we have everything to make your work easier. Shop now!
