Оrto-Phosphoric Acid as an Alternative to Hydrochloric Acid – For Cationic Bitumen Road Emulsions. Review

Abstract

In this article the cationic bitumen emulsions are characterized-as popular binder for various road emulsions. There are considered the specific features of cationic bitumen road emulsions' formulations. There are presented the functions and specificities of the acids application in cationic bitumen road emulsions. The literary review is presented on potentialities of ortho-phosphoric acids application instead of the traditional hydrochloric acid. Chemical peculiarities of application are presented (as well as advantages and drawbacks of application)-for both the traditional hydrochloric acid and forward-looking ortho-phosphoric acid. As the advantages of ortho-phosphoric acid application for cationic bitumen road emulsions one can mention: simple replacement of acid in soap solution preparation, less corrosive acid, higher pH emulsions, acid is easier to store, fewer fumes, not regulated in some countries, unlike hydrochloric acid. The potentialities are considered for application of ortho-phosphoric acid, as an effective component of cationic bitumen emulsion for application in various bitumen emulsion technologies, including the technologies for making protective slurry road pavements, among which the most widespread application was found by ortho-phosphoric acid in special fast-setting Slurry Surfacing systems, which possess a number of advantages over the same systems based on hydrochloric acid. The main of those advantages are as follows: such application eliminates the need for acid dopes in bitumen, provides a quick-traffic slurry system that works in cooler temperatures and at night, no need to change the usual latex or SBS grades, can use normal break retarders, mix controllable with cement in the field.

Hydrochloric and Orthophosphoric Acids Use in the Quick-Traffic Slurry Surfacing Mix

“…For further testing, the slurry-surfacing mix No. 3 was rejected, as far as the rates of cohesion strength buildup for the mix 0-5 mm were unsatisfactory in contradistinction to the investigations results [21,22]. Thus, the formulation of bitumen emulsion No.…”

“…It was noted that total surface activity determined by the methylene blue index (MB) is 15 ml, which exceeds the allowable norm (5-10 ml). However, previous studies [21,22] have indicated that slurry-surfacing mixtures on orthophosphoric acid make it possible to use an aggregate with high MB values.…”

“…The main advantages are: the possibility of using more common in Ukraine oxidized bitumen and nonoptimum (high-reactive) aggregates by methylene-blue criterion, quick slurry-surfacing structure formation and the possibility of laying slurry-surfacing mix in cold weather and at night time; orthophosphoric acid does not require getting license for handling pre-cursors and is less corrosive unlike concentrated hydrochloric acid. In the works [21,22] slurry-surfacing with application of orthophosphoric acid and Redicote EM44 emulsifier investigations are compared with traditional slurry-surfacing mixes, and efficiency of using system on orthophosphoric acid is proved.…”

Adhesion of Bituminous Binders With Aggregates in the Context of Surface Dressing Technology for Road Pavements Treatment

“…The analysis of scientific literature data has shown that the modern scientists pay the major attention to the study of bitumen emulsion component (with regard to surface dressing technology) (Zhdaniuk, 2008;Solodkyy, 2018;Sidun, 2020), as well аs to the methods for evaluation of adhesion between the components of surface dressing and non-skid qualities on the surface dressing done Pavlyuk, 2010;Pavlyuk, 2013).…”