3095-65-6Relevant academic research and scientific papers
An extensive investigation on nucleation, growth parameters, crystalline perfection, spectroscopy, thermal, optical, microhardness, dielectric and SHG studies on potential NLO crystal-Ammonium Hydrogen l-tartarte
Hanumantharao, Redrothu,Kalainathan,Bhagavannarayana,Madhusoodanan
, p. 388 - 399 (2013)
Ammonium Hydrogen l-tartarte (AMT), an organic nonlinear optical crystal was grown by slow evaporation method at ambient temperature. Solubility, metastable zone width and induction period of Ammonium Hydrogen l-tartarte in aqueous solution were determined. Good quality crystals were selected and characterized by Single crystal XRD, HR-XRD, FT-IR, 1H NMR, Mass, TGA-DTA, SEM, EDAX, optical and NLO studies. Single crystal XRD analysis revealed that the crystal system belongs to orthorhombic with cell parameters a = 7.65 A, b = 7.85 A and c = 11.07 A. High-resolution-X-ray diffraction (HR-XRD) analysis was carried out to study the crystalline perfection of the grown crystal. 1H NMR and FTIR spectrum thus confirmed the presence of functional groups of the grown crystal. Molecular mass of AMT was measured accurately by mass spectroscopic analysis. Surface features of the grown crystal were analyzed by SEM, AFM, chemical etching and the presence of elements in the compound was identified by EDAX analysis. Thermal behavior of the grown crystal has been studied by TG/DTA analysis. The recorded UV-Vis-NIR spectrum shows excellent transmission in the region of 190-1100 nm. The Vickers and Knoop's microhardness studies have been carried out on AMT crystals over a range of 10-50 g. Hardness anisotropy has been observed in accordance with the orientation of the crystal. Fluorescence spectral studies were carried in the range of 280-500 nm for the grown crystal. The SHG conversion efficiency and laser damage threshold were measured using an Nd: YAG laser (1064 nm).
A D-ethyl ester recovery and use in the production of L-(+)-tartaric acid method
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Paragraph 0045-0052, (2017/04/29)
The invention discloses a method for recycling and reusing L-(+)-tartaric acid in production of D-p-methyl sulfone phenyl ethyl serinate. The method comprises the following steps: (1), a L-(+)-calcium tartrate dihydrate crystal is recovered from L-ethyl ester mother liquor; (2), an L-(+)-tartaric acid double brine solution is recovered from D-p-methyl sulfone phenyl ethyl serinate mother liquor; (3), L-(+)-tartaric acid double hydrochlorination is performed; (4), L-(+)-tartaric acid is recovered through L-(+)-tartaric acid single hydrochlorination; and (5), processes of vacuum concentration, crystallization, separation, drying and the like are performed. An insert organic solvent is used for replacing a conventional water phase method to recover L-(+)-tartaric acid, the possibility of side reaction is avoided, the purity and specific rotation of a product can both reach the raw material quality standard, and L-(+)-tartaric acid can be directly and circularly applied to chiral resolution of D-p-methyl sulfone phenyl ethyl serinate. Different recovery processing technologies are adopted for different mother liquor of two components in the production process of D-p-methyl sulfone phenyl ethyl serinate, the product quality is improved remarkably, the whole recovery condition is mild, and the operation is simpler and easy to control.
