Vitamin K2, also known as MK-7 (menaquinone-7), is a crucial element for bone and cardiovascular health. Our client, a global vitamin supplement manufacturer, faced the challenge of meeting various product criteria, including microbiology, heavy metal content, and acid value (the quantity of free fatty acids).

Identifying the issue

One of the client’s batches exhibited an excessively high acid value, rendering it unusable. As a solution, we embarked on the task of re-purifying 350 kg of oil to reduce the acid value. However, the compound’s limited stability under UV radiation and alkaline conditions necessitated extreme caution throughout the process.

Methodology insight

Our journey began with 100 g laboratory studies which successfully lowered the acid value without difficulty (Figure 1). However, during the scale-up to 1 kg, we faced significant challenges with stirring and filtration due to the formation of soapy salts that clogged the system.

We devoted extensive effort to optimizing factors like stirring, temperature, reagent addition, and reaction duration. Additionally, we invested a significant amount of time in devising the best method for isolating pure oil. These insights paved the way for the final scale-up to 60 kg.

While initially challenging, we effectively managed a large 60 kg batch of crude oil within a relatively short timeframe. Neutralization took place in a 100 L stainless steel bioreactor, allowing vigorous stirring and precise temperature control under a protective nitrogen atmosphere (Figure 2). The filtration process, critical due to the substantial soap by-product formation, was considerably improved to prevent blockages through simple decantation.

Positive outcome

We are really proud of our achievements, successfully reducing the entire purification process from days to mere hours. In just 14 days, we effectively refined 350 kg of oil (Figure 3).