• 专利标题:   Preparing nano-graphene used as plugging agent in oil-based drilling fluid, comprises reacting graphite, oxidant i.e. ammonium persulfate and intercalating agent i.e. concentrated sulfuric acid, reacting with concentrated sulfuric acid and oxidant i.e. potassium permanganate, and gas-stripping.
  • 专利号:   CN115124034-A
  • 发明人:   DAI F, LI W, HUANG D, XIE G, LUO P, LI D, BAI Y
  • 专利权人:   UNIV SOUTHWEST PETROLEUM
  • 国际专利分类:   B82Y040/00, C01B032/19, C09K008/32, C09K008/46
  • 专利详细信息:   CN115124034-A 30 Sep 2022 C01B-032/19 202305 Chinese
  • 申请详细信息:   CN115124034-A CN10920684 02 Aug 2022
  • 优先权号:   CN10920684

▎ 摘  要

NOVELTY - Preparing nano-graphene comprises: (i) reacting graphite, first oxidant and intercalating agent to obtain modified graphite; (ii) reacting modified graphite, acid and second oxidant to obtain graphene pre-product; and (iii) gas-stripping graphene pre-product. USE - The method is useful for preparing nano-graphene, which is used as plugging agent in oil-based drilling fluid (all claimed). ADVANTAGE - The nano-graphene as plugging material has good dispersing effect in oil-based drilling fluid, and strong bearing capacity, and is capable of effectively plugging nano-level pore in stratum at lower concentration, delaying pore pressure transmission, and improving stratum bearing capacity. The oil-based drilling fluid has good rheology, and high plugging rate, which can greatly improve well wall stabilizing ability, and has good quality, safety and high efficiency drilling. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: nano-graphene, prepared by above method, where the average particle diameter of the nano-graphene is 110-750 nm, preferably 110-600 nm; and oil-based drilling fluid, comprising nano-graphene.