Takeshi Hagio

This study presents a method that will allow for the sustainable utilization of rice husk ash-SiO2 (RHAS), an agricultural-waste–derived material, as a bulky solid SiO2 source in the zeolite beta (BEA)/Fe3O4 composite (magnetic RHAS-BEA) synthesis via a dry-gel conversion method for the removal of paraquat, a typical herbicide, from aqueous solutions. Ultrasonic waves were used to facilitate the formation of uniform Fe3O4-contained dry precursor gel before converting to the magnetic BEA zeolite

Hydroxyapatite (HAp) is a type of calcium phosphate widely applied in the biomedical field. HAp is a main inorganic component of hard tissues of vertebrates and is a bioactive ceramic which shows a high biological affinity. The crystal of HAp exhibits an anisotropic nature depending on its crystal planes which is stemmed from its anisotropic crystal structure belonging to the hexagonal system. For instance, anions and acidic proteins are mainly adsorbed onto the a-plane of HAp crystals while cat

Given the scarcity of natural gold sources and associated mining challenges, the recovery of gold from secondary sources, such as electronic equipment waste (e-waste), becomes imperative. E-waste is typically treated with aqua regia to obtain highly acidic gold-containing solutions, which are subsequently processed by various methods to recover gold. Gold recovery materials offer numerous benefits but often exhibit insufficient selectivity, efficiency, and cost-effectiveness. To address this pro

Hydroxyapatite ceramics has been demonstrated to be an appropriate material for biomedical applications owing to its bioactivity and high biocompatibility. It has an anisotropic crystal structure that belongs to the hexagonal system, and two types of crystal planes mainly appear on its crystal, which are a-plane and c-plane. Since these two crystal planes are very different in atomic elements, numbers and arrangements, they exhibit different nature (anisotropy). For this reason, it is said that

Removal of organic compounds from wastewater is necessary to ensure that aquatic organisms are not adversely affected. In the past, it had been shown that zeolite-based systems provide good opportunities for wastewater treatment; however, most of the zeolite systems reported thus far face the disadvantages of sinking in water and saturated adsorption site. Therefore, in the current study, we attempted to develop zeolite-based composite systems with good floatability, adsorption capacity, and pho

Compositing diamonds with high thermally conductive metals, such as copper, have attracted much attention in recent years. In this study, we prepared copper/diamond composites by electroplating and investigated the effect of the surface functionalization of diamond on the interfacial adhesion of copper and diamond in the composite. Oxygen-containing groups were introduced on the diamond surface by a hydrothermal treatment and amino groups were further introduced using a silane coupling agent. Su

Abstract Conventionally, EAB‐type zeolites are crystallized by hydrothermal synthesis for many days under agitational synthesis conditions such as rotation or stirring. In the present study, EAB‐type zeolite is obtained by hydrothermal synthesis within 12 h under static synthesis conditions for the first time. The effects of crystallization temperature, aging of the precursor sol, and addition of seed crystals are investigated. The results reveal that EAB‐type zeolite can be obtained when using

MOR zeolite is an effective adsorbent for separating organic molecules from various solutions owing to its large windows of 0)65 × 0)70 nm and its relatively high silica-alumina ratio which provides higher hydrophobicity. Fine powdery MOR zeolite is desirable for adsorption of organic molecules considering its larger surface area; however, fine particles are difficult to remove from solutions after treatment. Intensification of magnetic susceptibility through combination with magnetic particles