Process for producing acicular goethite particles and acicular magnetic
iron oxide particles
    1.
    发明授权
    Process for producing acicular goethite particles and acicular magnetic iron oxide particles 失效
    制备针状针铁矿颗粒和针状磁性氧化铁颗粒的方法

    公开(公告)号:US5480571A

    公开(公告)日:1996-01-02

    申请号:US309743

    申请日:1994-09-21

    IPC分类号: C01G49/06 C01G49/08

    摘要: Disclosed herein are a process for producing acicular goethite particles comprising the step off: blowing an oxygen-containing gas into a ferrous salt reaction solution containing colloidal ferrous hydroxide or iron-containing colloidal precipitates which is obtained by reacting an aqueous ferrous salt solution with less than one equivalent of an aqueous alkali hydroxide solution, an aqueous alkali carbonate solution, or an aqueous alkali hydroxide and alkali carbonate solution based on Fe.sup.2+ in said aqueous ferrous salt solution, in the presence of ascorbic acid or a salt thereof so as to oxidize said colloidal ferrous hydroxide or iron-containing colloidal precipitates and to produce acicular goethite particles throught green rust; and a process for producing acicular magnetic iron oxide particles by reducing the acicular goethite particles obtained in the above process to produce acicular magnetite particles, and if necessary, oxidizing the acicular magnetite particles to obtain acicular maghemite particles, and if necessary, modifying the acicular magnetite or maghemite particles with Co or Co and Fe.sup.2+.

    摘要翻译: 本文公开了一种制备针状针铁矿颗粒的方法,包括以下步骤:将含氧气体吹入含有胶态氢氧化亚铁或含铁胶体沉淀物的亚铁盐反应溶液中,该溶液通过使亚铁盐水溶液与小于 一种碱金属氢氧化物水溶液,碱金属碳酸盐水溶液或碱金属氢氧化物和碱金属碳酸盐水溶液中,在所述含水亚铁盐水溶液中,在抗坏血酸或其盐的存在下,氧化所述胶体 含氢氧化铁或含铁胶体沉淀物,并通过绿锈生成针状针铁矿颗粒; 以及通过将上述方法中得到的针状针铁矿粒子还原而制造针状磁性氧化铁粒子的方法,制造针状磁铁矿粒子,根据需要,根据需要氧化针状磁铁矿粒子,得到针状磁赤铁矿粒子,根据需要,对针状磁铁矿 或具有Co或Co和Fe2 +的磁赤铁矿颗粒。

    Process for producing acicular geothite particles and acicular magnetic
iron oxide particles
    2.
    发明授权
    Process for producing acicular geothite particles and acicular magnetic iron oxide particles 失效
    生产针状地质颗粒和针状磁性氧化铁颗粒的方法

    公开(公告)号:US5378380A

    公开(公告)日:1995-01-03

    申请号:US22847

    申请日:1993-02-25

    IPC分类号: C01G49/06 C01G49/08

    摘要: Disclosed herein are a process for producing acicular goethite particles comprising the step of: blowing an oxygen-containing gas into a ferrous salt reaction solution containing colloidal ferrous hydroxide or iron-containing colloidal precipitates which is obtained by reacting an aqueous ferrous salt solution with less than one equivalent of an aqueous alkali hydroxide solution, an aqueous alkali carbonate solution, or an aqueous alkali hydroxide and alkali carbonate solution based on Fe.sup.2+ in said aqueous ferrous salt solution, in the presence of ascorbic acid or a salt thereof so as to oxidize said colloidal ferrous hydroxide or iron-containing colloidal precipitates and to produce acicular goethite particles throught green rust; and a process for producing acicular magnetic iron oxide particles by reducing the acicular goethite particles obtained in the above process to produce acicular magnetite particles, and if necessary, oxidizing the acicular magnetite particles to obtain acicular maghemite particles, and if necessary, modifying the acicular magnetite or maghemite particles with Co or Co and Fe.sup.2+.

    摘要翻译: 本文公开了一种制备针状针铁矿颗粒的方法,包括以下步骤:将含氧气体吹入含有胶态氢氧化亚铁或含铁胶体沉淀物的亚铁盐反应溶液中,该溶液通过使亚铁盐水溶液与小于 一种碱金属氢氧化物水溶液,碱金属碳酸盐水溶液或碱金属氢氧化物和碱金属碳酸盐水溶液中,在所述含水亚铁盐水溶液中,在抗坏血酸或其盐的存在下,氧化所述胶体 含氢氧化铁或含铁胶体沉淀物,并通过绿锈生成针状针铁矿颗粒; 以及通过将上述方法中得到的针状针铁矿粒子还原而制造针状磁性氧化铁粒子的方法,制造针状磁铁矿粒子,根据需要,根据需要氧化针状磁铁矿粒子,得到针状磁赤铁矿粒子,根据需要,对针状磁铁矿 或具有Co或Co和Fe2 +的磁赤铁矿颗粒。

    Method of decoloring colored concrete
    8.
    发明授权
    Method of decoloring colored concrete 失效
    消色色混凝土的方法

    公开(公告)号:US5993536A

    公开(公告)日:1999-11-30

    申请号:US018330

    申请日:1998-02-04

    IPC分类号: C04B14/30 C04B40/00 C09C1/36

    摘要: A method of decoloring a colored concrete, comprises adding to the colored concrete, a decoloring pigment comprising a titanium oxide pigment, or a titanium oxide pigment and a pigment having a complementary color relative to color of the colored concrete. Such method can decolore the color of the colored concrete residue which attaches to or remains in production facilities in order to return a color thereof to that of an ordinary plain concrete, without works or treatments for washing-out or removing the colored concrete residue which attaches to or remains in the production facilities, in which the works or treatments are required in the case where the production facilities are used for the production of an ordinary plain concrete after the colored concrete has been produced therein, and without works or treatments for purifying a waste water generated upon washing-out or removing the residue and for making the waste water harmless; and a pigment used therefor.

    摘要翻译: 一种脱色有色混凝土的方法,包括向有色混凝土中加入一种脱色颜料,该颜料包含二氧化钛颜料或二氧化钛颜料和相对于着色混凝土的颜色具有互补色的颜料。 这种方法可以将附着在或留在生产设施中的着色混凝土残留物的颜色去衍生,以便将其颜色返回到普通普通混凝土的颜色,而不用于清除或除去附着的有色混凝土残留物的作业或处理 在生产设施中使用或保留在生产设备用于生产有色混凝土后的普通普通混凝土生产设备的情况下的工程或处理,以及没有用于净化有色混凝土的工作或处理 在清洗或除去残渣并使废水无害化时产生的废水; 和用于其的颜料。