colemanite

Some of the commonly used commercial boron derivatives are borax, colemanite, ulexite, kernite, probertite and szaibelyite (Ozkan et al., 1997).

Summary: Boric acid, one of the boron products, is obtained from colemanite sulfuric acid process in some countries.

Sevinc, "Effects of colemanite waste, coal bottom ash and fly ash on the properties of cement," Cement and Concrete Research, vol.

Boron fertilisers in the form of very soluble B compounds such as sodium borate or borax ([Na.sub.2][B.sub.4][O.sub.7] x 10[H.sub.2]O) and boric acid ([H.sub.3]B[O.sub.3]) and less soluble B sources such as colemanite ([Ca.sub.2][B.sub.6][O.sub.11]] x 5[H.sub.2]0) and ulexite (NaCa[B.sub.5][O.sub.9] x 8[H.sub.2]O) have been added to soil to maintain plant growth (Wear and Wilson 1954).

[18] investigated the dissolution of colemanite ore with acetic acid and found that higher leaching agent amount in reaction medium elated the rate of product formation with the appearance of sparingly solid film layer which results in fall in leaching reaction.

Gerstley borate is composed of ulexite ([Na.sub.2]O 2CaO 5[B.sub.2][O.sub.3]3 16 [H.sub.2]O), with small amounts of colemanite (2CaO 3[B.sub.2][O.sub.3] 5[H.sub.2]O) and probertite ([Na.sub.2]O) 2CaO 5[B.sub.2] [O.sub.3] 10 [H.sub.2]O), resulting in low levels of pore water and much higher levels of chemically bound water.

Similar studies were reported in the use of calcinated colemanite ore waste [42] and acid 183 and acid green 25 onto shell of bittim [43].

The effectiveness of crushed ore colemanite as B source for rice crop under flooded calcareous soil was evaluated in a glass house study.

In the case of the last, higher specific surface means higher mechanical values, for example, (a) polymer concrete with clean sand have higher values than those with foundry sand [5]; (b) for concrete elaborated with epoxyresin, silica sand, hematite, and colemanite, the mechanical properties depend on the resin and hematite-colemanite concentrations; larger improvement for hematite is done [6]; (c) for concrete with waste marble as aggregate the splitting tensile strength decreases, and improvement on the elasticity modulus is produced [7].