A SEMI-CONTINUOUS PROCESS FOR THE SYNTHESIS OF A CATALYST FOR USE IN THE MANUFACTURE OF POLYOLEFINS

摘要

This invention provides a semi-continuous process and system thereof, for the synthesis of a narrow particle size distribution Zeigler Natta procatalyst for use in the manufacture of polyolefins comprising of following steps: (a) mixing a reaction mixture essentially consisting of titanium compound having at least one titanium halogen bond and a chlorinated solvent in feed section; (b) charging a first reactor with said reaction mixture; (c) continuously removing excess reactants from said first reactor as a filtrate through a filtrate section placed at the bottom of said first reactor; (d) feeding said filtrate to at least one further reactor connected to said first reactor to retain the carried over fine particles from said first reactor; continuously removing excess reactants from said at least further reactor as a filtrate through a filtrate section placed at the bottom of said at least one further reactor and, if desired, feeding said filtrate to next said at least one further reactor; (e) repeating step (d) for n number of times in series, wherein reactors are arranged in series or parallel; (f) subjecting the said filtrate from the last of said at least one further reactor to a distillation section to remove impurities and recover the distillate; and continuously charging the distillate from the distillation section to the feed section; wherein a desired equilibrium between fresh and recovered distillate and a desired resultant concentration of reactant feed are maintained; and (g) optionally treating the residue from distillation section with an alkali to obtain titanium hydroxide and calcining said titanium hydroxide to obtain titanium oxide as a by product.