Abstract: A resonance converter and a synchronous rectification driving method thereof are provided. The resonance converter includes a switch circuit having at least two first switches, a resonance circuit having a resonance frequency, a transformer, and a full-wave rectification circuit having two second switches each of which has a drain and a source and generates a channel resistance voltage when a current flows through the drain and the source. The synchronous rectification driving method includes steps as follow.

Abstract: A system and method are provided for producing Bisphenol-A (BPA) using direct crystallization of BPA in a single crystallization stage. In one embodiment the method comprises reacting Phenol and Acetone in the presence of a catalyst to form a product solution including Bisphenol-A and Phenol; removing a part of the Phenol from the product solution if required, and providing a selective amount of solvent, so as to obtain a product solution with the desired phase equilibrium behavior; and feeding the product solution with a selective composition to a crystallization stage operated at a selected temperature, so as to recover substantially pure Bisphenol-A in crystal form.

Abstract: A system and method for producing bisphenol-A (BPA) is provided. In particular, the present invention provides a system and method of producing bisphenol-A wherein the phase equilibrium behavior of a feed solution to a crystallizer is selectively controlled and adjusted to provide desired results. This provides a powerful tool, whereby certain operating conditions or variables of the bisphenol-A process can be selectively adjusted to generate desired phase equilibrium behavior. In general, bisphenol-A is produced from a reaction of phenol and acetone, forming a product solution including phenol, bisphenol-A, isomers of bisphenol-A, unreacted reactants and by-products. A solvent is provided in the product solution and the amount and composition of solvent in the product solution are selectively controlled to adjust the composition of the product solution fed to a crystallizer such that either crystalline bisphenol-A, or an adduct of bisphenol-A and phenol is crystallized from the product solution.

Abstract: A system and method are provided for producing Bisphenol-A (BPA) using direct crystallization of BPA in a single crystallization stage. In one embodiment the method comprises reacting Phenol and Acetone in the presence of a catalyst to form a product solution including Bisphenol-A and Phenol; removing a part of the Phenol from the product solution if required, and providing a selective amount of solvent, so as to obtain a product solution with the desired phase equilibrium behavior; and feeding the product solution with a selective composition to a crystallization stage operated at a selected temperature, so as to recover substantially pure Bisphenol-A in crystal form.

Abstract: A method is disclosed for separating gaseous silicon compounds from hydrogen and/or hydracids. Specifically, the method comprises the utilization of semi-permeable membranes for such gaseous separation. Particularly preferred is a composite membrane comprised of a coating separation layer of sulfonated polysulfone and a support layer of polysulfone. Mixtures of hydrogen and silane are particularly suitable for being separated by means of composite membrane separation.