Process for preparation and composition of stable aqueous solutions of boron zirconium chelates for high temperature frac fluids
US5217632A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 11, 1992 |
| Grant date | Jun 8, 1993 |
| Priority date | — |
| Expiry date | May 11, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/922
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a new process for preparing boron zirconium chelate solutions which are stable on the addition of acid bases, boiling, high dilution and/or aging. These chelates are useful in several industries, especially in the petroleum industry for frac fluids for treating oil or gas bearing strata especially deep hot wells. The boron zirconium chelates are prepared by forming a mixture of ammonium hydroxide, water soluble amines, sodium or potassium zirconium alpha hydroxy carboxylates selected from lactates, citrates, tartrates, glycolates, maliates, saccharates, gluconates, glycerates and mandelates, with polyols such as glycerin, erythritol, arabitol, xylitol, sorbitol, dulcitol, mannitol, inositol, monosaccharides and disaccharides and with water. This mixture is blended and then boric acid or borax as a source of boron is added and the pH is adjusted using inorganic or organic bases and/or inorganic carbonates and bicarbonates. The boron zirconium chelate solutions contain 0.1-3.0% by weight ZrO.sub.2, 5-25% by weight polyols; 2-20% by weight of B.sub.2 O.sub.3 with a weight ratio of B.sub.2 O.sub.3 :ZrO.sub.2 between 5:1 and 20:1. The pH is maintained wi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.