Preparing process adapted for electronic grade solid hydroxyethylidene diphosphonic acid

Abstract

The invention discloses a making method of electron-grade solid hydroxy trimethylphosphine, which comprises the following steps: (1) cleaning autoclave, condenser and relative equipment clearly; (2) weighing liquid hydroxy trimethylphosphine into autoclave; stirring; (3) dehydrating in the vacuum under 35-120 deg.c; (4) cooling to 40-90 deg.c naturally; adding seed with quantity at 50-50000ppm; (5) cooling to indoor temperature; stewing; aging 4-20h; (7) centrifuging at high-speed centrifuger to dehydrate with velocity at 500-5000r / min; (8) packing the solid HEDP with activity over 95% and arsenic content less than 7ppm.

Description

technical field

[0001] The invention relates to a preparation process of high-purity solid hydroxyethylene diphosphonic acid (HEDP), in particular to a kind of electronic-grade solid hydroxyethylene diphosphonic acid (HEDP) which can be used as a cleaning agent and a metal surface treatment agent in the electronics industry. Preparation process of diphosphonic acid. Background technique

[0002] Hydroxyethylidene diphosphonic acid (hereinafter referred to as HEDP) is an organic phosphonic acid scale and corrosion inhibitor, which can form stable complexes with various metal ions such as iron, copper, zinc, etc., and can dissolve oxidation on the metal surface. things. HEDP is generally used as an anti-scaling agent for circulating cooling water, oil field water injection and printing and dyeing water. Its acid and alkali resistance and chlorine oxidation resistance are better than other organic phosphonic acids (salts). It can form six-ring chelates with metal ions in wate...

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