Slack wax

Feedstocks for this very flexible process are usually vacuum distillates, deasphalted oils, residues (hydrotreated or not), as well as by-products from other processes such as extracts, paraffinic slack waxes, distillates from visbreaking and coking, residues from hydrocracking, converted in mixtures with the main feedstock. 

On the other hand, intermediate paraffin distillates contain paraffin waxes and waxes intermediate in properties between paraffin and microwaxes. Thus, the solvent dewaxing process produces three different slack waxes depending on whether light, intermediate, or heavy paraffin distillate is processed. The slack wax from heavy paraffin distillate may be sold as dark raw wax, the wax from intermediate paraffin distillate as pale raw wax. The latter is treated with lye and clay to remove odor and improve color. 

Tomas-Alonso, F., Angosto, L.A. Olmos, and Munecas Vidal, M.A. (2004) Selecbve separabon of normal paraffins from slack wax using the molecular sieve adsorpbon technique. Sep. Sci. Technol, 39,1577. 

Crude scale wax the wax product from the first sweating of the slack wax. 

Foots oil the oil sweated out of slack wax named from the fact that the oil goes to the foot, or bottom, of the pan during the sweating operation. 

Scale wax the paraffin derived by removing the greater part of the oil from slack wax by sweating or solvent de-oiling. 

Slack wax the soft, oily crude wax obtained from the pressing of paraffin distillate or wax distillate. 

Paraffin wax from a solvent dewaxing operation is commonly known as slack wax, and the processes employed for the production of waxes are aimed at deoiling the slack wax (petroleum wax concentrate). 

Molasses Paraffin Peat Petroleum pitch Polyvinyl alcohol Potato starch Refined asphalts Resins (natural and synthetic) Rosin Sawdust Seaweed Slack wax Slaughterhouse refuse Straw (pulped) Sucrose Sugars Tanning liquors (tannic acid) Thermoplastic powders Vegetable pulp Water Wheat starch Wood pulp Water... 

The waxy oil is fractionated to produce an oily wax called slack wax. This is separated by solvent extraction and fractionated into different melting point ranges to give waxes with a variety of physical characteristics. Paraffin waxes consist mainly of straight-chain alkanes (also called normal alkanes), with small amounts (3-15%) of branched-chain alkanes (or iso-alkanes), cycloalkanes, and aromatics. Microcrystalline waxes contain high levels of branched-chain alkanes (up to 50%) and cycloalkanes, particularly in the upper end of the molecular weight distribution. Paraffin waxes contain alkanes up to a molecular mass of approximately 600 amu, whereas microcrystalline waxes can contain alkanes up to a molecular mass of approximately 1100 amu. 

Oil in Wax Contents in Slack Wax from DILCHILL and Conventional Dewaxing ... 

MAX-DEWAX ) and deoiling (MAX-DEOIL ) to separate 25% to 50% of the MEK-toluene solvents. The solvent produced is at the same temperature as the filtrate involved. The advantages cited for this technology are increased throughput and reduced oil content of the slack wax in the case of MAX-DEWAX , with no increase in energy use. 

Shell has produced group HI base stocks with Vis greater than 145 at their Petit Couronne, France, refinery since the 1970s. The feed used was slack wax which was catalytically isomerized and then dewaxed, and presumably finished if that last step was part of the process—no details appear to have been published. 

Effect of Slack Wax Injection on Isoparaffin Product Levels (Low Viscosity Group III Production)... 

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