Erratum to: Preparation of Hydrotalcite–Hydroxyapatite Material and Its Catalytic Activity for Transesterification of Soybean Oil

Hydrotalcite–hydroxyapatite material (HT–HAp) was produced by co-precipitation at room temperature (10 ≤ pH ≤ 11) with ultrasonic homogenization and hydrothermal treatment for 24 h/80 °C. The main physical–chemical characteristics were studied and the catalytic potential of the material was evaluated in transesterification of soybean oil into methyl esters. Best results were obtained at 240 °C, 4 h and 12:1 molar ratio methanol/oil: conversion rate of 80.4%. Free glycerol and free acids were not observed at these conditions. HT–HAp is a promising material for catalysis and adsorption studies. Graphical Abstract