Slack Wax
Wax is a petrochemical product of refineries so this is highly related to oil in refinery towers wax is near to bitumen and their difference is in the color. Bitumen is quite black but wax is dark to light brown. First product of refinery is slack wax which can be heavy or light according to its carbon chain and chemical elements.
Slack wax was considered as rubbish 50 years ago and refineries paid extra cost to send slack wax to the suburb to be unloaded and vanished there but now it is a very famous and useful petrochemical product.
Slack wax is processed by DE-oiling and DE-coloring in factories the end product is paraffin wax depending the process we will have fully refined and semi refined paraffin wax from 0.5% to 7% oil content. What remains of extracting oil from slack wax and producing paraffin wax is residue wax or foots oil even this product has a role in industries nowadays.
slack wax has also some grades based on oil content 5% to 35% and melting point 50 °C to 55 °C, its color differs from yellow to brown, slack wax light and heavy is used mainly forparaffin wax manufacturing, matches industry.
Slack wax packing is bag for lower oil grades 5% to 15% but for higher oil contents like light slack wax 30% oil the only packing is steel drum to avoid leakage. Slack wax has only industrial use and can not be added to any cosmetic or food product before complete process.