Decomposition of aluminum nitrate
    2.
    发明授权
    Decomposition of aluminum nitrate 失效
    分解硝酸铝

    公开(公告)号:US4223000A

    公开(公告)日:1980-09-16

    申请号:US61297

    申请日:1979-07-27

    IPC分类号: C01F7/30

    摘要: There is described a method for the decomposition of aluminum nitrate crystals to alumina comprising the steps of:(a) melting the aluminum nitrate crystals;(b) evaporating from the melted crystals in a once through evaporator at the boiling temperature of the mixture and for a time sufficient to remove water and associated nitric acid and to provide a fluid having an alumina concentration of at least about 18% by weight;(c) decomposing the product of step (b) at a temperature of between about 150.degree. and about 200.degree. C. and recovering the heat of condensation of the resultant vapors;(d) further decomposing the product of step (c) in a fluidized bed decomposer at a temperature of between about 300.degree. and about 400.degree. C. to reduce the residual nitrate concentration in the product to between about 5 and about 10 weight percent;(e) decomposing the product of step (d) in a fluidized bed decomposer at a temperature of between about 500.degree. and about 800.degree. C. to reduce the residual nitrate concentration in the product to below about 3 percent by weight; and(f) calcining the product of step (e) at a temperature of at least about 1000.degree. C.

    摘要翻译: 描述了将硝酸铝晶体分解成氧化铝的方法,包括以下步骤:(a)熔融硝酸铝晶体; (b)在混合物的沸腾温度下在一次性蒸发器中从熔融的晶体中蒸发出足够的时间以除去水和相关的硝酸,并提供具有至少约18重量%的氧化铝浓度的流体; (c)在约150至约200℃的温度下分解步骤(b)的产物,并回收所得蒸气的冷凝热; (d)在流化床分解器中在约300℃至约400℃的温度下进一步分解步骤(c)的产物,以将产物中的残留硝酸盐浓度降低至约5至约10重量%; (e)在流化床分解器中在约500至约800℃的温度下分解步骤(d)的产物,以将产物中的残留硝酸盐浓度降低至低于约3重量%; 和(f)在至少约1000℃的温度下煅烧步骤(e)的产物。

    Basic aluminum nitrate crystallization
    3.
    发明授权
    Basic aluminum nitrate crystallization 失效
    碱性硝酸铝结晶

    公开(公告)号:US4256714A

    公开(公告)日:1981-03-17

    申请号:US61296

    申请日:1979-07-27

    IPC分类号: C01F7/76 C01F7/66

    CPC分类号: C01F7/66

    摘要: There is described a process for preparing large crystals of basic aluminum nitrate (BAN) from a nitric acid feed solution containing Al.sub.2 O.sub.3 values comprising the steps of:(1) evaporating water and nitric acid from the solution in a single step evaporation performed at a temperature of between about 270.degree. and about 450.degree. F. and at a pressure of between about atmospheric and about 60 psig to produce an evaporated liquor comprising at least about 16% alumina by weight;(2) holding the evaporated liquor in a quiescent state for a period of between about 20 minutes and about two hours within the temperature range of about 270.degree. F. to about 340.degree. F.;(3) injecting water into the product of step 2, the water being added in an amount sufficient to adjust the composition of the conditioned liquor to a composition expressible as the sum of two components(1) ANN (Al.sub.2 O.sub.3.6HNO.sub.3.15H.sub.2 O or Al(NO.sub.3).sub.3.9H.sub.2 O), and(2) The desired crystal product BAN or Wiseite(a) BAN (Al.sub.2 O.sub.3.2HNO.sub.3.5H.sub.2 O or Al(OH).sub.2 NO.sub.3.2.OH.sub.2 O). or(b) Wiseite (Al.sub.2 O.sub.3.2HNO.sub.3.4H.sub.2 O or Al(OH).sub.2 NO.sub.3.1.5H.sub.2 O) to precipitate large crystals of BAN; and(4) separating the large crystals.

    摘要翻译: 描述了从含有Al 2 O 3值的硝酸进料溶液制备碱式硝酸铝(BAN)的大晶体的方法,包括以下步骤:(1)在温度下进行的单步蒸发中从溶液中蒸发水和硝酸 在约270°至约450°F之间并且在约大气压至约60psig的压力下产生包含至少约16重量%氧化铝的蒸发液; (2)在约270°F至约340°F的温度范围内将蒸发的液体保持在静止状态约20分钟至约2小时; (3)将水注入步骤2的产品中,加入的水量足以将调理液体的组成调节为可表示为两种组分(1)ANN(Al2O3.6HNO3.15H2O或Al (NO 3)3·4H 2 O)和(2)所需的晶体产物BAN或者Wiseite(a)BAN(Al2O3.2HNO3.5H2O或Al(OH)2NO3.2.OH2O)。 或(b)Wiseite(Al2O3.2HNO3.4H2O或Al(OH)2NO3.1.5H2O)沉淀出大的BAN晶体; 和(4)分离大晶体。

    Nitric acid reconstitution
    4.
    发明授权
    Nitric acid reconstitution 失效
    硝酸重组

    公开(公告)号:US4312852A

    公开(公告)日:1982-01-26

    申请号:US175925

    申请日:1980-08-06

    申请人: John L. Dewey

    发明人: John L. Dewey

    IPC分类号: C01B21/40 C01B21/42

    CPC分类号: C01B21/40

    摘要: There is described a process for the reconstitution of NO.sub.X gases produced by the thermal decomposition of metal nitrates to nitric acid comprising the steps of:1. contacting the NO.sub.X gases in counter-current relationship in one or more packed columns with cooled 50 to 60 percent nitric acid to remove as nitric acid a major portion of the originally introduced NO.sub.X values and provide an acid solution leaving the column having a temperature below about 180.degree. F. to remove as nitric acid a major portion of the originally introduced NO.sub.X values;2. compressing the residual gases from step 1 to from about 2 to about 6 atmospheres absolute;3. contacting the compressed gases from step 2 with from about 50 to about 60 percent nitric acid in a packed absorption column in counter-current relationship to remove substantially all of the remaining NO.sub.X values from the gas stream as HNO.sub.3 ; and4. recovering 50-60% nitric acid as it accumulates.

    摘要翻译: 描述了通过将金属硝酸盐热分解产生的NO x气体重构为硝酸的方法,包括以下步骤:1.将一种或多种填充柱中的NOX气体以逆流关系与冷却的50至60% 硝酸作为最初引入的NOX值的主要部分硝酸除去,并提供离开柱子的酸溶液,其温度低于约180°F,以除去作为最初引入的NOX值的主要部分的硝酸; 2.将来自步骤1的残余气体压缩至约2至约6大气压绝对值; 3.将来自步骤2的压缩气体与填充吸收塔中的约50%至约60%的硝酸以逆流关系接触,从而从气流中基本上除去所有剩余的NO x值,作为HNO 3; 并回收50-60%的硝酸积累。