In this work we obtain the astrophysical reaction and production rates for the two-particle radiative capture processes α + n + n → 6 He + γ and α + α + n → 9 Be + γ. The hyperspherical adiabatic expansion method is used. The four-body recombination reactions α + α + n + n → 6 He + α, α + n + n + n → 6 He + n, α + α + n + n → 9 Be + n and α + α + α + n → 9 Be + α are also investigated.