A 3He purification system based on a new method using ultrathin polymer tubes

Abstract

A new 3He purification system has been developed for use with an ion source of a cyclotron. The method of purification is based on the principle of gas diffusion through an ultrathin polymer layer. The essentials of this system are two modules consisting of many thin polymer tubes. Two oil-free diaphragm compressors pressurize the contaminated gas to the modules through which purified 3He seeps out, and force it onto the ion source for recycling continuously. The gas compositions at several points of the system are investigated with a quadrupole mass analyzer. The total system is capable of supplying 3He with almost constant purity of more than 99% in all operating time for 3He ion acceleration at the cyclotron. The system was initially charged with 61 3He to keep the flow rate of 2 cm 3/min at standard temperature and pressure (STP) for a three-days operation. Neither periodic attention to the system nor regeneration of the modules was required in many continuous four- or five-days runs.