Process for separating paraxylene comprising at least two
crystallization stages at high temperature
    2.
    发明授权
    Process for separating paraxylene comprising at least two crystallization stages at high temperature 失效
    在高温下分离包含至少两个结晶阶段的对二甲苯的方法

    公开(公告)号:US6147272A

    公开(公告)日:2000-11-14

    申请号:US860558

    申请日:1997-06-30

    CPC分类号: C07C7/14

    摘要: A process for producing paraxylene of very high purity from a charge containing a mixture of aromatic hydrocarbons having 7 to 9 carbon atoms in which at least a portion of the charge is made to circulate in a zone suited to enrich a first fraction of paraxylene and at least a portion of said first fraction is purified by at least one high-temperature crystallization in at least one crystallization zone, the process being characterized in that said first paraxylene-enriched fraction is crystallized in a crystallization zone comprising at least two crystallization stages (50,70) at high temperature, and advantageously between +10 and -25 .degree. C.The paraxylene enriching zone can be a crystallization at very low temperature, a selective adsorption or a toluene disproportionation zone.

    摘要翻译: PCT No.PCT / FR95 / 01739 Sec。 371日期:1997年6月30日 102(e)日期1997年6月30日PCT 1995年12月27日PCT PCT。 WO96 / 20908 PCT出版物 日期1996年7月11日一种从含有7至9个碳原子的芳香族烃的混合物的电荷产生具有非常高纯度的对二甲苯的方法,其中使至少一部分电荷在适于富集第一 对二甲苯的馏分和至少一部分所述第一馏分通过在至少一个结晶区中的至少一个高温结晶来纯化,所述方法的特征在于所述第一对二甲苯富集部分在结晶区中结晶,所述结晶区至少包括 两个结晶阶段(50,70)在高温下,有利地在+ 10和-25℃之间。对二甲苯富集区可以是非常低温下的结晶,选择性吸附或甲苯歧化区。

    Process for production of paraxylene comprising a high-temperature
crystallization with at least one stage and a partial melting of the
crystals
    3.
    发明授权
    Process for production of paraxylene comprising a high-temperature crystallization with at least one stage and a partial melting of the crystals 失效
    包括具有至少一个阶段的高温结晶和晶体部分熔融的对二甲苯的生产方法

    公开(公告)号:US6111161A

    公开(公告)日:2000-08-29

    申请号:US875278

    申请日:1997-07-21

    CPC分类号: C07C7/005 C07C7/14

    摘要: A process for production of paraxylene from a charge containing C7-C9 aromatic hydrocarbons in which a first fraction is enriched to at least 30% weight with paraxylene and this fraction is purified by at least one high-temperature crystallization in at least one crystallization zone. Said first fraction is crystallized in a crystallization zone at high temperature T1 and advantageously between +10 and -25.degree. C., crystals in suspension in a mother liquor are recovered, the crystals are separated from the mother liquor in at least a first separation zone, the crystals obtained are partially melted in at least a zone for partial melting and a suspension of crystals is recovered, the crystals in suspension are separated and washed in at least one separation and washing zone and pure paraxylene crystals and washing liquor are recovered, and pure crystals are optionally completely melted and a liquid stream of melted paraxylene is collected.

    摘要翻译: PCT No.PCT / FR96 / 00078 Sec。 371日期1997年7月21日 102(e)日期1997年7月21日PCT 1996年1月17日PCT公布。 公开号WO96 / 22262 日期1996年7月25日一种从含有C 7 -C 9芳烃的电荷生产对二甲苯的方法,其中第一部分通过对二甲苯富集至少30%重量,该馏分通过至少一种高温结晶在 至少一个结晶区。 所述第一馏分在高温T1和有利地在+ 10至-25℃之间的结晶区中结晶,回收在母液中的悬浮液晶体,在至少第一分离区 所获得的晶体在至少部分熔融的区域中部分熔融,并且回收晶体悬浮液,将悬浮液中的晶体分离并在至少一个分离和洗涤区域中洗涤,并回收纯对二甲苯晶体和洗涤液,并且 纯晶体任选地完全熔化并且收集熔融的对二甲苯的液流。

    Process for production of paraxylene comprising a high-temperature crystallization with at least one stage and a partial melting of the crystals
    4.
    发明授权
    Process for production of paraxylene comprising a high-temperature crystallization with at least one stage and a partial melting of the crystals 有权
    包括具有至少一个阶段的高温结晶和晶体部分熔融的对二甲苯的生产方法

    公开(公告)号:US06399846B1

    公开(公告)日:2002-06-04

    申请号:US09649597

    申请日:2000-08-29

    IPC分类号: C07C714

    CPC分类号: C07C7/005 C07C7/14 C07C15/08

    摘要: A process for production of paraxylene from a charge containing C7-C9 aromatic hydrocarbons in which a first fraction is enriched to at least 30% weight with paraxylene and this fraction is purified by at least one high-temperature crystallization in at least one crystallization zone. Said first fraction is crystallized in a crystallization zone at high temperature T1 and advantageously between +10 and −25° C., crystals in suspension in a mother liquor are recovered, the crystals are separated from the mother liquor in at least a first separation zone, the crystals obtained are partially melted in at least a zone for partial melting and a suspension of crystals is recovered, the crystals in suspension are separated and washed in at least one separation and washing zone and pure paraxylene crystals and washing liquor are recovered, and pure crystals are optionally completely melted and a liquid stream of melted paraxylene is collected.

    摘要翻译: 从含有C 7 -C 9芳烃的电荷中生产对二甲苯的方法,其中第一部分通过对二甲苯富集至少30重量%,并且该部分通过在至少一个结晶区中的至少一个高温结晶来纯化。 所述第一馏分在高温T1和有利地在+ 10至-25℃之间的结晶区中结晶,回收在母液中的悬浮液晶体,在至少第一分离区 所获得的晶体在至少部分熔融的区域中部分熔融,并且回收晶体悬浮液,将悬浮液中的晶体分离并在至少一个分离和洗涤区域中洗涤,并回收纯对二甲苯晶体和洗涤液,并且 纯晶体任选地完全熔化并且收集熔融的对二甲苯的液流。

    Process for separating paraxylene comprising at least one
crystallization stage at high temperature and at least one clay
treatment upstream from the adsorption zone
    5.
    发明授权
    Process for separating paraxylene comprising at least one crystallization stage at high temperature and at least one clay treatment upstream from the adsorption zone 失效
    用于在高温下分离包含至少一个结晶阶段的对二甲苯和在吸附区上游的至少一种粘土处理的方法

    公开(公告)号:US6063978A

    公开(公告)日:2000-05-16

    申请号:US860559

    申请日:1997-06-30

    CPC分类号: C07C7/12 C07C7/005 C07C7/14

    摘要: A process for separating paraxylene at very high purity from a charge of xylene isomers, comprising a selective adsorption of a fraction that is rich in paraxylene, at least one high-temperature crystallization of this fraction, and an isomerization of the fraction depleted of paraxylene, recycling the mother liquor to the selective adsorption optionally via a clay treatment followed optionally by a distillation of the treatment effluent, and optionally introducing the mother liquor into a distillation unit, wherein the crystallization can comprise several high-temperature stages.

    摘要翻译: PCT No.PCT / FR95 / 01738 Sec。 371日期:1997年6月30日 102(e)日期1997年6月30日PCT 1995年12月27日PCT PCT。 WO96 / 20907 PCT公开号 日期1996年7月11日一种从二甲苯异构体的电荷中分离出非常高纯度的对二甲苯的方法,包括富含对二甲苯的馏分的选择性吸附,该馏分的至少一种高温结晶和 部分耗尽对二甲苯,任选地经由粘土处理任选地将母液循环到选择性吸附,随后任选地通过蒸馏处理流出物,以及任选地将母液引入蒸馏单元中,其中结晶可以包括几个高温阶段。