Distilling Naphtha from Car Degreaser

Naphtha is a very useful low boiling hydrocarbon solvent, usually containing carbon chains of C5-C10. Uses include: degreasing, dissolving wax, removing adhesives, thinning oil based paint, lighter fuel, spot cleaning and many others. In the United States, naphtha can easily be obtained as VM&P Naphtha (Varnish Makers' and Painters') or camping fuel. However, in China it is much more difficult to obtain, and therefore I will have to distill it from an OTC product which contains it. Luckily, while looking around I discovered this brand of car degreaser, for use before spray painting a car that contains between 50-75% of naphtha. This was therefore a great source for my purposes.

Here is a photo showing the ingredients in the can:

To translate, it contains by percentage:
Light hydrotreated naphtha: 50-75%
Xylene: 2.5-10%
Ethyl Acetate: 2.5-10%
Ethylbenzene: 1-2.5%

The boiling points are as follows:
Naphtha: 50-120°C
Xylene: ~140°C
Ethyl Acetate: 77.1°C
Ethylbenzene: 136°C

Therefore, because most components have a boiling point above that of the naphtha, it can be separated by simple distillation. Since I want to have a large reserve of naphtha, a 2L flask was used to process a 1L batch of the degreaser.

1L of Degreaser in Flask

Process Breakdown:
1. Heating was started and the mixture began to boil within a few minutes.
2. First drops of distillate made it over at a still-head temperature of 56°C.
3. The fraction boiling all the way up to 120°C was collected in one container.
4. Heating was stopped after this point and everything allowed to cool.
5. The yield was approximately 800ml, with 150ml left in the flask and 50ml lost due to evaporation.

Entire Distillation Setup

Conclusion:
The process went extremely smoothly and without any major issues. The process should have effectively separated the naphtha from the ethylbenzene and the xylene due to the large difference in boiling point, but it will not have separated the ethyl acetate much if at all, since its boiling point lies right in the middle of the collected fraction. However, since there was no noticeable pause at the boiling point of the ethyl acetate, and the product has no significant smell of the ester, it was likely present in the lower range of percentages, less than 5%. This is not a significant contamination for my intended purposes and thus no further purification was attempted.

Make a Simple Storage Drawer

For the longest time I have been having storage issues in my lab/workshop. There is just so much stuff to store away but so little storage space. I wanted this project to be a quick project because some of my things were just sitting on the floor. I also wanted this to be a simple project because I don't have a table saw so it had to be do-able with just a circular saw.

As with all woodworking project, a plan is important for making sure everything will fit together right. But a plan doesn't have to be complicated. I drew a simple sketch in just a few minutes.









The next step was to cut the sides of the drawer. A tip when cutting is to mark out which side of the wood is the waste so you know which side to be careful with.












After the two sides were cut it was time to cut the two strips of wood that the drawers would ride on. Sometimes when a piece of wood is too thin to be held, some painters tape can be used.











To accommodate the bottom self and hold it securely, a dado needs to be cut. To ensure that the dado would be exactly the same on both sides, it needs to be cut on both boards simultaneously.











For strength, the rails that the drawers will ride on are both glued and screwed onto the sides.












The plywood for the drawers themselves are cut to size glued together.














The top of the drawer is glued on and the outer part is complete.

Spontaneous Combustion of Linseed Oil

Spontaneous Combustion is Real!

Spontaneous combustion describes the phenomenon where substances catch fire all by themselves. For example, some substances like white phosphorus ignite on contact with air. Substances where exposure to air causes fire are known as pyrophoric. Other examples of spontaneous combustion include damp hay bales and trash heaps igniting due to heat generated by microbes. Of significance to the average person is the spontaneous combustion of rags soaked in linseed oil. Many instances of this occurring have been recorded. Thus I decided to conduct the following experiment as a public service announcement.

Materials:

• 8 rags
• 1 can of boiled linseed oil
• 1 empty metal gallon can
• 1 Thermometer
• Fire extinguisher
• Stopwatch

Procedure: 

1. The rags were laid out and linseed oil was poured on until they were covered evenly.
2. The soaked rages were gently wadded up and placed into the gallon can while making sure they were not packed too tightly.                       
3. The thermometer was inserted into the midst of the rags. 
4. The timer was started and the temperature recorded every 10 minutes until the rags caught fire. 

Ambient temperature 100˚F (37˚C)

Start: <140˚C

10min: <140˚C

20min: <140˚C

30min: <140˚C

40min: <140˚C

50min: <140˚C

60min: <140˚C

70min: <140˚C

80min: <140˚C

90min: <140˚C

100min: 190˚C

110min: 235˚C First signs of smoke

120min: >250˚ 

130min: >250˚ 

140min: >250˚ 

150min: >250˚ 

160min: >250˚ 

170min: >250˚ 

180min: Maxed out

190min: Maxed out

 

3 hours 45 minutes fire begins

Make a Container for a Burette

The first burette I owned broke because I was storing it clamped in the butterfly clamp. Thus to keep better care of my second burette, I made a special case for it using some PVC pipe.

Materials:

• 50mm PVC pipe
• Scrubbing sponge
• Drill
• 2-50mm PVC pipe end cap
• Measuring tape
• Scissors
• PVC cement
• Handsaw

 Procedure:

The length of the burette was measured using the measuring tape and the PVC pipe cut to the same length.

The diameter of the pipe was traced onto the sponge and cut out using a pair of scissors.

The sponge cut-out was inserted into one end of the pipe.

PVC cement was used to glue one of the caps onto the end of the pipe with the sponge.

A hole slightly wider than the diameter of the burette was drilled into the second cap.

The container is now complete!