The present invention relates to a process for converting natural gas into higher alkanes having at least 3 carbon atoms (C3+), preferably at least 4 carbon atoms (C4+). It comprises a stage (1) for separating the components of the natural gas so as to isolate (a) methane and (b) alkanes having at least 2 carbon atoms (C2+), a stage (2) for non-oxidative methane coupling, comprising contacting the methane thus isolated with a metal catalyst (C1) capable of producing, in contact with alkane, reactions involving the splitting and recombining of carbon-carbon and/or carbon-hydrogen and/or carbon-metal bonds, so as to form a mixture (M1) comprising ethane and hydrogen, optionally a stage (3) comprising separating and isolating ethane from the mixture (M1), a stage (4) for ethane metathesis, comprising contacting the ethane isolated in stage (3) or the mixture (M1) obtained in stage (2) and preferably the alkanes (C2+) isolated in stage (1) with a metal catalyst (C2) capable of producing, in contact with alkane, reactions involving the splitting and recombining of carbon-carbon and/or carbon-hydrogen and/or carbon-metal bonds, so as to form a mixture (M2) comprising higher alkanes (C3+), preferably (C4+) and methane, and a stage (5) comprising separating and isolating said higher alkanes from the mixture (M2). Methane can be separated and isolated in stage (5) and preferably recycled in stage (2).
本发明涉及一种将天然气转化为至少具有3个碳原子(C3+),优选至少具有4个碳原子(C4+)的高碳
烷烃的过程。它包括以下阶段:(1)分离天然气的组分以隔离(a)
甲烷和(b)至少具有2个碳原子(C2+)的
烷烃;(2)非氧化
甲烷偶联阶段,包括将隔离的
甲烷与能够在碱
金属催化剂(C1)的作用下产生涉及碳-碳和/或碳-氢和/或碳-
金属键的裂解和
重组反应的
烷烃接触,从而形成包含
乙烷和氢的混合物(M1),可选地,包括(3)阶段,其中分离并隔离来自混合物(M1)的
乙烷;(4)
乙烷醚交换阶段,包括将在阶段(3)中隔离的
乙烷或在阶段(2)中获得的混合物(M1)以及优选在阶段(1)中隔离的
烷烃(C2+)与能够在碱
金属催化剂(C2)的作用下产生涉及碳-碳和/或碳-氢和/或碳-
金属键的裂解和
重组反应的
烷烃接触,从而形成包含较高碳
烷烃(C3+),优选(C4+)和
甲烷的混合物(M2);(5)阶段,其中分离并隔离所述较高碳
烷烃从混合物(M2)中。
甲烷可以在阶段(5)中分离并隔离,优选在阶段(2)中回收。