耐水低磷氟溶出相变磷石膏砌块的制备及应用  

Preparation and Application ofWater-Resistant Phase-Change Phosphogypsum Blocks with Low Dissolution of Phosphate and Fluoride Ions

作　　者：孙方圆 周昌林 谈云志 刘杨 杨杰 Fangyuan Sun;Changlin Zhou;Yunzhi Tan;Yang Liu;Jie Yang(College of Materials and Chemical Engineering,China Three Gorges University,Yichang 443002,China;Hubei Three Gorges Laboratory,Yichang 443002,China;College of Civil Engineering and Architecture,China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡大学材料与化工学院,湖北宜昌443002 [2]湖北三峡实验室,湖北宜昌443002 [3]三峡大学土木与建筑学院,湖北宜昌443002

出　　处：《高分子材料科学与工程》2024年第10期46-56,共11页Polymer Materials Science & Engineering

基　　金：湖北省自然科学基金联合基金(2024AFD160);湖北省建设科技计划项目(JK2024092);湖北三峡实验室开放基金(SC211002)。

摘　　要：将磷石膏(PG)作为原材料制备建材砌块是逐步消解PG大量堆存问题的主要方法之一。将相变储能材料与磷石膏砌块(PGB)相结合,制备出具有相变储热能力的建筑节能砌块可为被动式超低能耗建筑提供高效的围护结构调温系统。但是PGB耐水性差,且PO_(4)^(3-)和F-会对环境产生污染,使其应用受到极大限制。针对该问题,文中首先开展了高焓值形状稳定有机相变球粒的制备研究;然后以相变球粒、PG、聚丙烯酸(PAA)为原材料制备相变PGB;最后采用不同聚合物对砌块进行包覆处理,以提高PGB耐水性。结果表明,相变石蜡、膨胀石墨和苯乙烯-乙烯-丁二烯-苯乙烯共聚物质量比为93:4:3时,可得到焓值为208.1 J/g,导热系数为0.8 W/(m·K)的形状稳定相变球粒;PAA,H_(2)O和PG质量比为2.5:22:100时,制备的PGB的抗压强度可达16.5 MPa;聚氨酯包覆PGB的PO_(4)^(3-)溶出浓度低于0.01 mg/L,F-的溶出浓度为0.04 mg/L;通过模拟太阳光照试验,含有相变球粒的PCB-32和PCB-41比PGB的室温分别低4.9℃和4.3℃。为实现PG在建材中的规模化资源利用提供了一种新的路径。Using phosphogypsum(PG)as raw material to produce building blocks is one of the primary methods to gradually solve the problem of large-scale stockpiling of PG.By combining phase change materials with phosphogypsum blocks(PGB),energy-saving building blocks with phase change materials could be produced,offering an effective temperature regulation system for passive ultra-low energy buildings.However,PGB suffers from poor water resistance,and the dissolution of PO_(4)^(3-)and F-poses environmental concerns,significantly limiting its application.Firstly,the preparation of high enthalpy shape stable organic phase change pellets was studied.Then,using phase change pellets,PG,and polyacrylic acid(PAA)as raw materials,PGBs with phase change materials were prepared.Finally,different polymers were used to coat the blocks to improve the water resistance of PGB.The results reveal that when the mass ratio of paraffin wax,expanded graphite,and styrene-ethylene-butadiene-styrene copolymer is optimized at 93:4:3,shape-stable phase change pellets with an enthalpy value of 208.1 J/g and a thermal conductivity of 0.8 W/(m·K)could be obtained.Moreover,when the mass ratio of PAA,H_(2)O,and PG is set at 2.5:22:100,the compressive strength of PGB could reach a remarkable level of 16.5 MPa.Notably,the polyurethane-coated PGB exhibits a significantly reduced dissolution concentration of PO_(4)^(3-)below 0.01 mg/L and F-at 0.04 mg/L.Under simulated solar illumination conditions,PCB-32 and PCB-41 containing phase change pellets demonstrate indoor ambient temperatures lower than PGB by 4.9℃and 4.3℃,respectively.This study provides a new path for the large-scale utilization of PG in building materials.

关 键 词：磷石膏 磷酸根 氟离子 耐水性 相变材料 

分 类 号：TQ117.375[化学工程—无机化工]