Ford's answers to the NHTSA 6.7 Investigation

Biodiesel quality control started off as non-existent, and it hardly mattered much with pre-2000 engines.

But over time, the stuff flogged out there became more and more unsuitable for a modern engine, and standards came in:

The most important aspects of biodiesel production to ensure trouble free operation in diesel engines are:

* Complete Reaction
* Removal of Glycerin
* Removal of Catalyst
* Removal of Alcohol
* Absence of Free Fatty Acids

SPECIFICATION FOR
BIODIESEL (B100) – ASTM D6751-07a

March 2007

Biodiesel is defined as the mono alkyl esters of long chain fatty acids derived from vegetable oils or animal
fats, for use in compression-ignition (diesel) engines. This specification is for pure (100%) biodiesel prior to use
or blending with diesel fuel. #

Property ASTM Method Limits Units
Calcium & Magnesium, combined EN 14538 5 max ppm (ug/g)
Flash Point (closed cup) D 93 93 min. Degrees C
Alcohol Control (One of the following must be met)
1. Methanol Content EN14110 0.2 Max % volume
2. Flash Point D93 130 Min Degrees C
Water & Sediment D 2709 0.05 max. % vol.
Kinematic Viscosity, 40 C D 445 1.9 - 6.0 mm
Sulfated Ash D 874 0.02 max. % mass
Sulfur
S 15 Grade
S 500 Grade

D 5453
D 5453

0.0015 max. (15)
0.05 max. (500)
Copper Strip Corrosion D 130 No. 3 max.
2
/sec.

% mass (ppm)
% mass (ppm)


Cetane D 613 47 min.
Cloud Point D 2500 Report Degrees C
Carbon Residue 100% sample D 4530* 0.05 max. % mass
Acid Number D 664 0.50 max. mg KOH/g
Free Glycerin D 6584 0.020 max. % mass
Total Glycerin D 6584 0.240 max. % mass
Phosphorus Content D 4951 0.001 max. % mass
Distillation, T90 AET D 1160 360 max. Degrees C
Sodium/Potassium, combined EN 14538 5 max ppm
Oxidation Stability EN 14112 3 min hours
Workmanship Free of undissolved water, sediment, & suspended matter
BOLD = BQ-9000 Critical Specification Testing Once Production Process Under Control

* The carbon residue shall be run on the 100% sample.
# A considerable amount of experience exists in the US with a 20% blend of biodiesel with 80% diesel fuel (B20).
Although biodiesel (B100) can be used, blends of over 20% biodiesel with diesel fuel should be evaluated on a
case-by-case basis until further experience is available.

See the document here:

www.biodiesel.org/pdf_files/fuelfactsheets/prod_quality.pdf



Or here:

Quality Control

All biodiesel production facilities should be equipped with a laboratory so that the quality
of the final biodiesel product can be monitored. It is also important to monitor the quality of the
feedstocks.

One strategy used by many producers is to draw a sample of the oil (or alcohol) from
each delivery and use that sample to produce biodiesel in the laboratory. This test can be fairly
rapid (1 or 2 hours) and can indicate whether serious problems are likely in the plant.
Measuring feedstock quality can usually be limited to acid value and water content.
These are not too expensive ($500 for the acid value equipment and $5,000 for the water
measurement equipment) and can be operated by less experienced technicians.
To monitor the completeness of the reaction according to the total glycerol level specified
in ASTM D 6751 requires the use of a gas chromatograph and a skilled operator. Large
producers will find that having this equipment on-site is necessary. Commercial laboratories (i.e.
Magellan Midstream Partners) are available that can analyze the samples but the cost is $80-
$150/test and the time required may be several days. Smaller producers will need to use a more
robust production process involving extra methanol and probably multiple reaction steps. Then
the product quality can be monitored through periodic testing by an outside laboratory.
Other possibilities for monitoring the transesterification reaction and assessing fuel
quality are methods based on spectroscopy (such as near- infrared spectroscopy) or physical
properties (such as viscometry). These methods, although they are not (yet?) ASTM methods,
are usually faster and easier to use than gas chromatography. However, some of them require
extensive calibration. They also cannot accurately quantify glycerol at the low levels called for
in the ASTM standard. To circumvent this, comparison to a reaction and product known to meet
ASTM standards is needed.

www.uiweb.uidaho.edu/bioenergy/biodieselED/publication/01.pdf