The invention relates to a preparation method of food-grade
microcrystalline wax. The preparation method comprises the following steps that blended oil comprising paraffin-based
slag-reduced deasphalted oil and naphthenic base
slag-reduced deasphalted oil is used as a
raw material, is fed into a first reaction
bed layer and then undergoes a hydrotreatment modification reaction; the
reaction product is fed into a stripping
tower and the stripped product is fed into a second reaction
bed layer and undergoes a hydrofining reaction to produce hydrofined product oil; the hydrofined product oil is
cut by atmospheric and vacuum
fractionation equipment to form a heavy
lubricant component having a temperature of 480-750 DEG C; the heavy
lubricant component and an
acetone-benzol dewaxing
solvent are mixed; the mixture is cooled to below -15 DEG C; the cooled mixture is filtered so that dewaxed filtrate and deoiled
wax are obtained; the deoiled
wax is mixed with carclazyte by stirring; and the mixture is filtered so that the carclazyte is removed and the food-grade
microcrystalline wax is obtained. The food-grade
microcrystalline wax has Seybolt color number greater than +25, a drop
melting point of 67-92 DEG C, a
needle penetration degree of 15-35(1 / 10mm),
oil content of 0.85-3.0%,
sulfur and
nitrogen content less than 1
microgram per
gram and heavy
metal and
arsenic content less than 1mg / kg.