Method for producing hydrophobic silica granules

A process for producing hydrophobic silica granular insulation materials, comprising the following steps, in the order given:

• i) coating a mixture consisting of hydrophilic silica, optionally one or more IR opacifiers, optionally one or more antistatic agents, and optionally one or more fillers other than hydrophilic silica, with a hydrophobing composition consisting of organosilicon compounds which eliminate not more than 1 wt. %, based on the weight of the hydrophobing composition, of volatile organic compounds, HCl, or ammonia, selected from the group consisting of organosilanes, organosiloxanes, silicone resins, and mixtures thereof,
• ii) after not more than 24 hours, deaerating the mixture from step i),
• iii) compacting the mixture from step ii) to a target bulk density, and
• iv) granulating during the compaction in step iii),
• wherein at least steps i) and ii) are conducted at temperatures of 55° C. or less.