A review of closed-loop supply chain models

Closed-loop supply chain (CLSC) networks have been studied extensively in the literature due to the cost and environmental optimization in operations. A CLSC consists of forward and reverse supply chains. This paper reviews the literature of CLSC networks. 225 peer-reviewed articles that have been published in international journals from 1997 to 2020 are gathered and analysed. The aim is to answer the following main questions: (i) What is the problem domain in CLSC? (ii) Which techniques are utilized frequently in CLSC? (iii) What elements, variables, and objectives are the main focus in the field? (iv) What are the gaps in the literature? After reviewing the literature, observations are provided. Finally, the evaluations conclude suggested improvements and potential future directions in this research field.