Entanglement purification protocol for a mixture of a pure entangled   state and a pure product state
  We present an entanglement purification protocol for a mixture of a pure entangled state and a pure product state, which are orthogonal to each other. The protocol is combination of bisection method and one-way hashing protocol. We give recursive formula for the rate of the protocol for different states, i.e. the number of maximally entangled two-qubit pairs obtained with the protocol per a single copy of the initial state. We also calculate numerically the rate for some states. 
Mikolaj Czechlewski, Andrzej Grudka, Satoshi Ishizaka, Antoni Wojcik