Forward osmosis (FO) has been extensively investigated and demonstrated its advantages in a range of FO applications over the past decade. However, challenges still remain in terms of the lack of both efficient FO membranes and appropriate draw solutes for practical FO applications. To promote the advancement of FO technology, considerable efforts have been made in exploring novel FO membranes and draw solutes in recent years. This paper will provide a short review on the progress of both FO membranes and draw solutes. First of all, a brief overview on FO principle is given. Then the progress in FO technology related to FO membrane and draw solute is presented with specific examples. Finally, challenges and future directions of FO technology in exploring efficient FO membranes and promising draw solutes are also highlighted. This article may provide new insights into the future development of FO technology and promote practical FO applications.

Membrane engineering is one of the disciplines most involved in the technological innovations necessary to face the problems characterizing the world today and in future such as water shortage, raw material depletion, and energy consumption. Membrane operations contribute to solving these problems, and the potentialities of membrane operations have been widely recognized in the last few years. In this work, an overview of membrane applications and their perspectives in the field of membrane materials, membrane modelling and water treatment will be analyzed. The scope of this study is to show how membranes, membrane operations and their integration could contribute to the redesign of membrane engineering in the logic of the process intensification strategy.

President Kennedy’s dream of obtaining fresh water from seawater seemed has been realized as a great scientific achievement. As Norihito Tambo predicted, seawater reverse osmosis desalination (SWRO) has become a major technology in Middle Eastern countries. SWRO requires less energy compared with the distillation method. Even Middle Eastern countries, where the distillation method is still a major technology, have started to adopt the RO method in new desalination plants in accordance with government policy and following the trend of developing larger (half mega-ton per day and larger) so-called Mega-SWRO plants. With these trends in the global market, the requirements of sustainable SWRO desalination as green desalination for the 21 ^st century are as follows: (1) conservation of energy resources: renewable energy, (2) innovation of desalination technologies: new advanced membrane and membrane systems, (3) reduction of marine pollution: green desalination. The government-supported Mega-ton water system project has been conducted to solve issues related to (2) and (3). The combination of a low pressure SWRO membrane and a low-pressure, two-stage, and high-recovery SWRO system, also referred to as a SWRO-PRO hybrid system, it has enabled 20% energy reduction and 30% energy saving in total. Likewise, low environmental impact as green desalination has established a reliable operation using less chemical and chemical cleaning. In terms of low-cost renewable energy, in particular, solar energy is now available to solve issues related to renewable energy. By combining these sophisticated technologies, desalinated water has become affordable at $ 0.50/m ³ or less (as low as $ 0.28/m ³). SWCC has announced their future plans for SWRO. The main topic is directed to brine mining to obtain precious materials from the brine of SWRO. This plan will be connected to water and green hydrogen for a sustainable future.