State of art of natural inhibitors of calcium carbonate scaling. A review article

The formation of calcium carbonate in water has some important implications in geoscience researches, ocean chemistry studies, CO2 emission issues and biology. In industry, the scaling phenomenon may cause technical problems such as reduction of heat transfer efficiency in cooling systems and obstruction of pipes. The use of chemicals which act as antiscalant is a common approach in the control of scale deposition. However, inorganic nitrogen and phosphorous compounds are involved in eutrophication process. Therefore, it is of prime importance to find alternative solutions, i.e. green inhibitors of scale formation. This last decade, several new scale inhibitors, that are more ecological compared with conventional inhibitors, have been reported in the literature. Plant extracts have been also recently used as new green antiscalants. Indeed, as they can be easily extracted and are environmentally friendly, they represent an interesting alternative source of natural organic molecules. In this review, a focus of some green antiscalants derived from petrochemicals has been reported. Then the efforts done those last years to obtain green inhibitors, either by using natural organic molecules or extracted from plants were summarized. Such green inhibitors might be used in various technical areas, i.e. energy, water, food and beverages industries. (C) 2014 Elsevier B.V. All rights reserved.