Solubility and Metastable Zone Width of 1-Keto-1,2,3,4-tetrahydro-6-methylcarbazole in Acetone

Abstract

The solubility of 1-keto-1,2,3,4-tetrahydro-6-methylcarbazole (KTMC) in acetone in the temperature range from 18 to 55 °C was determined by the residue solid technique and the polythermal method using a heat flow calorimeter with turbidity measurement capacities. The results were correlated using a polynomial equation. Utilizing the polythermal method, the metastable zone has also been determined. The broadening of the metastable zone with increasing cooling was observed from 0.05 to 2.0 °C·min-1.

A new interpretation of metastable zone widths measured for unseeded solutions

“…In the first category are included those techniques which detect change related to the amount of grown nuclei, and in the second are included those which detect change in solution concentration. Methods using naked eye [2,4,7,9,11], a particle counter [7,9,12] and a turbidity meter [3,8,[13][14][15] are classified into the first group, and techniques using an FTIR spectrometer [9], an ultrasound sensor [10,16,17], a densitometer [8] and electrical conductivity [18] were categorized into the second. Fujiwara et al [9], for instance, employed a focused beam reflectance probe (FBRM) to determine MSZWs for aqueous solutions of paracetamol.…”

Nucleation kinetics of paracetamol–ethanol solutions from induction time experiments using Lasentec FBRM®

“…The measured metastable zone width (MSZW) is also known to be affected by the nucleation detection technique utilised [3,4]. Numerous techniques have been employed to detect nucleation, such as electrical conductivity [5,6], ultrasound velocity [3,7,8], Focused Beam Reflectance Measurement (FBRM s ) [9][10][11], turbidity [3,5,12] and from the heat of crystallisation [13].…”

“…It is generally advisable to operate stirred tank reactors (STR) with wall baffles in place, due to the improved level of mixing of the solution. However, a large majority of publications on the estimation of the nucleation kinetics, by means of MSZW and induction time experiments, utilise unbaffled vessels [1,[3][4][5][6][7][8][10][11][12][13]16,22,24]. The direct effect, if any, of the presence of a baffle on the nucleation kinetics has never been reported, to the authors' knowledge.…”

On the induction period for crystallization in solute−solvent systems by polythermal method

“…The abbreviations AO, NTO and KTMC denote ammonium oxalate, 3‐nitro‐1,2,4‐triazol‐5‐one and keto‐1,2,3,4‐tetrahydro‐6‐methylcarbazole, respectively. The data on metastable zone width were obtained by the observation of detection of crystallization in the solutions during their cooling at constant rates R by abrupt decrease in green laser light intensity transmitted through investigated solutions for the KNO 3 −water system , by the naked eye and attenuated total reflection fourier transform infrared (ATR FTIR) spectroscopy for AO−water system , by the naked eye in the solutions for NTO−water , and by turbidity measurements in the solutions for KTMC−acetone systems .…”