Application of pyrophyllite in high-temperature treated building materials

Abstract

Phyllosilicate mineral pyrophyllite is predominantly used in the ceramic industry because it exhibits high refractoriness. Due to its thermal transformation into mullite, pyrophyllite is stable at elevated temperatures, making it a suitable mineral additive for refractory non-shaped materials and various ceramic shaped products. In this study, pyrophyllite is employed as 50 % clay replacement in the ceramics and up to 30 % cement replacement in mortars. Physico-mechanical properties were investigated. The firing shrinkage in the ceramics treated at 1200 °C was reduced by pyrophyllite addition. Pyrophyllite acted as additional pozzolana during cement hydration. Within the microstructure, it formed micro-reinforcement in the shape of crystalline folia, which improves the mechanical properties of ordinary Portland cement, high aluminate cement, and blended cement mortars. The investigation proved the efficiency and suitability of pyrophyllite employed as a substitution for clay in ceramics and a cement replacement in mortars.

Phyllosilicate mineral pyrophyllite is predominantly used in the ceramic industry because it exhibits high refractoriness. Due to its thermal transformation into mullite, pyrophyllite is stable at elevated temperatures, making it a suitable mineral additive for refractory non-shaped materials and various ceramic shaped products. In this study, pyrophyllite is employed as 50 % clay replacement in the ceramics and up to 30 % cement replacement in mortars. Physico-mechanical properties were investigated. The firing shrinkage in the ceramics treated at 1200 °C was reduced by pyrophyllite addition. Pyrophyllite acted as additional pozzolana during cement hydration. Within the microstructure, it formed micro-reinforcement in the shape of crystalline folia, which improves the mechanical properties of ordinary Portland cement, high aluminate cement, and blended cement mortars. The investigation proved the efficiency and suitability of pyrophyllite employed as a substitution for clay in ceramics and a cement replacement in mortars.

Филосиликатни минерал пирофилит се претежно користи у керамичкој индустрији јер показује високу ватросталност. Због своје термичке трансформације у мулит, пирофилит је стабилан на повишеним температурама, што га чини погодним минералним додатком за ватросталне необликоване материјале и различите керамичке обликоване производе. У овом раду пирофилит је коришћен као замена за 50 % глине у керамици и до 30 % замене за цемент у малтерима. Испитивана су физичко-механичка својства. Скупљање при печењу у керамици третираној на 1200 °C смањено је додавањем пирофилита. Пирофилит се понашао као додатни извор поцоланског материјала током хидратације цемента. Унутар микроструктуре формирао је микроарматуру у облику кристалне фолије, што је побољшало механичка својства малтера на бази обичног Портланд цемента, високоалуминатног цемента и мешаних цемента. Истраживањем је доказана ефикасност и погодност пирофилита који се користи као замена за глину у керамици и замена за цемент у малтерима.