Freeze stable tetrakis(hydroxymethyl) phosphonium sulfate formulations
A composition comprising: (a) tetrakis(hydroxymethyl)phosphonium sulfate (THPS); (b) water; and (c) methanol; wherein the weight percentages of (a), (b) and (c) are within the area on a ternary phase diagram for (a), (b) and (c) bounded by four points: (A) 5% THPS/58% water/37% methanol; (B) 5% THPS/36% water/59% methanol; (C) 65% THPS/27% water/8% methanol; and (D) 65% THPS/29% water/6% methanol.
1. A composition comprising:
(a) tetrakis(hydroxymethyl)phosphonium sulfate (THPS); (b) water; and (c) methanol; wherein the weight percentages of (a), (b) and (c), normalized to total 100%, are within an area on a ternary phase diagram bounded by four points: (A) 5% THPS/58% water/37% methanol; (B) 5% THPS/36% water/59% methanol; (C) 65% THPS/27% water/8% methanol; and (D) 65% THPS/29% water/6% methanol; wherein the composition comprises no more than 5 wt % of substances other than (a), (b) and (c).
2. The composition of claim 1 in which the area is defined by points: (E) 9% THPS/57% water/34% methanol; (F) 9% THPS/34% water/57% methanol; (G) 65% THPS/27% water/8% methanol; and (H) 65% THPS/29% water/6% methanol.
3. The composition of claim 1 in which the composition comprises no more than 1 wt % of substances other than (a), (b) and (c).
4. A composition comprising about 50% THPS/28% water/22% methanol.